研究者データベース

GAUTAM PITAMBAR(ゴータム ピタンバル)
創成研究機構
准教授

基本情報

所属

  • 創成研究機構

職名

    准教授

学位

  • 理学博士 (北海道大学)
  • Master of Science (Leningrad Mining Institute)

ORCID ID

  • 0000-0001-8297-4359

プロフィール

  • 2003/9 - date: Hokkaido University
    1994-2003 - Multiple short-term (2 months to 1 year) stays as
    visiting researcher (DFG Gastwissenschaftler & Humboldt
    Fellow) at University of Tuebingen, Germany
    1983/7 - 2003/8: Tribhuvan University
    1978/9 - 1983/6: St. Petersburg Mining Institute

研究キーワード

  • 大学ランキング指標   研究IR   サイエンス マッピ   計量書誌学   環境磁気学   環境地球物理学   古地磁気学   科学計量学   堆積祖   層位・古生物学   礁性石灰岩   三畳紀   古環境   地質学   古海洋   ネパール   粒度分析   カトマンズ盆地   テクトニクス   中新世   シワリク層群   堆積相   磁気層序学   帯磁率   

研究分野

  • 環境学 / 環境影響評価・環境政策
  • 地球惑星科学 / 地質学

職歴

  • 2008年07月 - 現在  北海道大学・創成研究機構准教授
  • 2005年04月 - 2008年03月  北海道大学・理学研究院特任准教授
  • 2003年09月 - 2005年03月  北海道大学・理学研究院特別研究員 (21世紀COEプログラム)
  • 1990年 - 2003年08月  Tribhuvan University (Nepal)Lecturer
  • 1983年07月 - 1986年01月  Trichandra College (Nepal)Assistant Lecturer

学歴

  • 1987年04月 - 1990年03月   北海道大学   大学院理学研究科   地質鉱物学課
  • 1978年09月 - 1983年06月   Leningrad Mining Institute   Department of Applied Geophysics
  • 1974年 - 1977年   Trichandra College (Kathmandu)   Physical Science Group

所属学協会

  • American Geophysical Union   Nepal Geological Society   

研究活動情報

論文

  • ゴータム ピタンバル
    Journal of Contemporary Eastern Asia 18 (1) 7 - 29 2019年07月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    This study describes an approach for comparative bibliometric analysis of scientific publications related to (i) individual or several departments comprising a university, and (ii) broader integrated subject areas using multiple disciplinary schemes. It uses a custom dataset of scientific publications (ca. 15,000 articles and reviews, published during 2009-2013, and recorded in the Web of Science Core Collections) with author affiliations to the research departments, dedicated to science, technology, engineering, mathematics, and medicine (STEMM), of a comprehensive university. The dataset was subjected, at first, to the department level and discipline level analyses using the newly available KAKEN-L3 classification (based on MEXT/JSPS Grants-in-Aid system), hierarchical clustering, correspondence analysis to decipher the major departmental and disciplinary clusters, and visualization of the department-discipline relationships using two-dimensional stacked bar diagrams. The next step involved the creation of subsets covering integrated subject areas and a comparative analysis of departmental contributions to a specific area (medical, health and life science) using several disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, SCOPUS 27 subject areas, OECD Frascati 38 subordinate research fields, and KAKEN-L3 66 subject categories. To illustrate the effective use of the science mapping techniques, the same subset for medical, health and life science area was subjected to network analyses for co-occurrences of keywords, bibliographic coupling of the publication sources, and co-citation of sources in the reference lists. The science mapping approach demonstrates the ways to extract information on the prolific research themes, the most frequently used journals for publishing research findings, and the knowledge base underlying the research activities covered by the publications concerned.
  • Gautam Pitambar
    北海道歯学雑誌 38 (1) 2 - 15 0914-7063 2017年09月 [査読無し][通常論文]
     
    This paper gives a brief overview of the scientific publications related to Hokkaido University (HU) in general and its Graduate School/Faculty/School of Dental Medicine (HU-DENT) in particular. It focuses on the bibliometric analysis of the peer-reviewed scientific publications (articles and reviews in journals with journal impact factor, almost exclusively in English) covering a 10-yrs period (2006-2015). The bibliographic data and citation impact indicators were extracted respectively from the Web of Science (WoS) core collections and InCites managed formerly by Thomson Reuters but now by Clarivate Analytics. Several research performance indicators (number of papers, percent share relative to the world, average citation per paper, category normalized citation impact (CNCI), percent papers belonging to top 10% by citation, and international co-authorship) using various disciplinary schemes (ESI22, WoS 251, KAKEN-L3) both at the university and department (HU-DENT) levels are used to assess the research output and impact and to identify major international collaborators, the effect of collaboration on citation impact, and so on. The use of science mapping to visualize the words, authors, subject areas, journals etc. relationships is illustrated by some concrete examples related to HU-DENT. In view of the close connections between bibliometric and university ranking indicators, a brief description of the aspects of world university rankings is also given with emphasis on the differences in the QS and THE World University Rankings. The latest rankings data are used to benchmark the Japanese Research Universities RU11 aiming at positioning Hokkaido University among them.
  • ゴータム ピタンバル
    Scientometrics 2017年09月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    This study (http://rdcu.be/wDf9) attempts to use bibliometry as a tool for exploration of the passage of development of the science and technology through analysis of the scientific publications from a developing country by taking into account its state of higher education and the unique political, economic and geo-bio-environmental conditions. It deals with Nepal considering its scientific output during 1966–2016 reflected as publications indexed in the Web of Science Database. Preliminary examination of the publication record for Nepal reveals a number of the following characteristics: (1) low volume, negligible growth and lack of distinct trend until 1989; (2) a marked growth followed by stagnation linked to political instability during the next 15 years; and (3) recovery and accelerated growth thereafter. Research publications during 2004–2013 increased thrice compared to 1994–2003, with expansion and shifts in disciplinary profile expressed in Essential Science Indicators 22 fields. Detailed bibliometric analysis of the 2004–2013 publications (3011 articles and reviews) from Nepal suggests the citation impact of about the world average, but very high (76%) average international co-authorship. The disciplinary profile is diverse judging from seven most productive fields (clinical medicine, plant and animal science, environment/ecology, geosciences, agricultural sciences, and chemistry) with 4–40% national disciplinary share. Clinical medicine, geosciences and agricultural sciences exhibit relatively high impact. Fields with the smaller share (< 3%), such as molecular biology and genetics, economics and business, psychiatry and psychology, materials science, and biology and biochemistry, exhibit citation impact distinctly higher than the world average. Publications from Nepal show the presence of a vast international collaborative network that is dominated by authors affiliated to institutions in the USA, India, UK, Japan, South Korea and Germany. Based on the analysis of the disciplinary diversity and the national versus global relative disciplinary shares, Nepal’s publication profile is inferred to be a hybrid of the ‘bio-environmental’ and ‘western’ models. Concerning the state of the development of science and technology in Nepal during 2004–2013, the high dependence on international collaboration in the internationally visible publications in most of the bio-environmental, physico-chemical and engineering fields points to basically a ‘building-up stage’. In clinical medicine (with a large share of public health) and geosciences, however, Nepal has demonstrated research strengths evident from the high citation impact in these fields. Moreover, the available data suggest that significant advances were made in higher education sector in both fields during the last 25 years. Despite the notable negative effect of the prolonged domestic armed political conflict on the research activities and acquisition of new data in the field-based sciences, the post-conflict period shows signs of recovery in both domestic and international collaborations leading to again an accelerated growth in scientific publications.
  • ゴータム ピタンバル
    2017 6th IIAI International Congress on Advanced Applied Informatics (IIAI-AAI) 202 - 207 2017年07月 [査読有り][通常論文]
     研究論文(国際会議プロシーディングス) 
    This study explores a country-level bibliometric analysis to extract bibliographic coupling (BC) communities as clusters of documents coupled through publications in their reference lists using the BiblioTool software. The 2004-2013 research output from Nepal represented by relatively small dataset of 3,011 documents (peer reviewed articles and reviews) indexed as core collections in the Web of Science (WoS) database was used. Setting a threshold of 10 documents, twenty-five BC communities, each with 12-443 documents, which provide a comprehensive picture on the research themes characterized by diverse items (keywords, subjects, journals, institutions, countries, authors, references, and title words) were discriminated. Twelve communities (i.e., 48%) deal with medical; health sciences (maternal; child health; tropical infectious diseases; cancer & cardiovascular diseases; mountain sickness; blindness) closely linked also with social aspects; 4 communities with earth, environment and biodiversity (tectonics and natural hazards; environmental pollution, remediation and conservation; wild-life preservation); 3 communities with agriculture and veterinary sciences (pathogens of major crops (maize, wheat, rice); crop yields, plant genes, and dairy farming); 3 communities with nanomaterials and metal-alloys; 2 communities with pharmacology including ethnomedicine, and one community of 12 documents is related to galactic observations. These new results provide wider insights on the research volume; diversity, international collaboration and the contributors (academic, national; international, governmental; non-profit agencies, etc.) engaged in research in Nepal.
  • 2016 5th IIAI International Congress on Advanced Applied Informatics, July 10-14, 2016, Kumamoto, Japan 2016年07月 [査読有り][通常論文]
     研究論文(国際会議プロシーディングス)
  • ゴータム ピタンバル
    IIAI International Congress on Advanced Applied Informatics 2015 (IIAI AAI 2015) 468 - 471 2015年07月 [査読無し][招待論文]
     研究論文(研究会,シンポジウム資料等) 
    This study explores a practical approach to decipher the department-discipline relationships between the organizational research units dedicated to natural science, technology, engineering & medical (STEM) fields and 22 disciplinary categories used in Essential Science Indicators database (ESI 22 fields), for a Japanese national university as seen in a set of peer-reviewed journal publications (articles & reviews) indexed in the Web of Science (WoS) Core Collection database for a 5-years period. The procedure involved several steps such as (i) identification of publications of each organizational research unit through disambiguation of the affiliation data; (ii) assigning each publication to the corresponding ESI field based on journal title; (iii) aggregating bibliometric information of all publications for each research unit and discipline, and (iv) performing multivariate analysis, e.g., clustering and correspondence analysis, to extract proximity relationships and internal structures that enable regrouping the obtained data and visualizing them using two-dimensional plots and bar diagrams. This approach may be easily adapted for analysis using other available disciplinary (subject areas or categories) schemes. Moreover, such analysis can be further extended to lower hierarchical levels, such as research divisions or research teams comprising a complex multidisciplinary department. The proposed affiliation-based analysis is useful for initial understanding the disciplinary contribution of the university departments to overall research output, e.g., for analysis of ranking based on performance for past 5-6 years tracing past history. It can be easily adapted to the bottom-up research performance analysis (based on current researchers)required for research administration or research strategy formulation based on the research output of the immediate past.
  • Gautam Pitambar, Kodama Kota, Enomoto Kengo
    Journal of Contemporary Eastern Asia 13 (1) 19 - 37 2014年04月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    In an attempt to develop comprehensive evidence-based methods for evaluation of the R&D per-formance of cross-disciplinary projects, a joint bibliometric analysis of patents and publications was performed for two industry-university-government collaborative projects aimed at commer-cialization: Hokkaido University Research & Business Park Project (2003-2007; 63 inventors; 176 patents; 853 papers), and Matching Program for Innovations in Future Drug Discovery and Medical Care – phase I (2006-2010; 46 inventors; 235 patents; 733 papers). Besides the simple output indicators (for five years period), and citations (from the publication date to the end of 2012), science maps based on the network analysis of words and co-authorship relations were generated to identify the prominent research themes and teams. Our joint analysis of publica-tions and patents yields objective and mutually complementing information, which provides bet-ter insights on research and commercialization performance of the large-scale projects. Hence, such analysis has potential for use in the industry-university project’s performance evaluation. Keywords: triple helix; bibliometry; patent metrics; science mapping; cross-disciplinary; indus-try-university-government collaboration
  • GAUTAM Pitambar, YANAGIYA Ryuichi
    Scientometrics 93 (1) 101 - 111 0138-9130 2012年10月 [査読有り][通常論文]
  • Gautam, P.; Blaha, U.; Appel, E.;
    Journal of Nepal Geological Society 37 67 - 76 2012年 [査読有り][通常論文]
     研究論文(学術雑誌)
  • Gautam, P. and Ulak, P. D. and Paudayal, K. N. and Gyawali, B. R. and Bhandari, S.
    Geophysical Journal International 190 (3) 1378 - 1392 0956540X (ISSN) 2012年 [査読有り][通常論文]
     
    A molasse sequence comprising 1.5-km-thick sediments of the Lower and Middle Siwaliks Group in the sub-Himalayan North Belt along the Tinau Khola River in west-central Nepal was studied for the low-field magnetic susceptibility and anisotropy using single core specimens of siltstone/sandstone from 127 stratigraphic levels. The magnetic fabric comprises primary sedimentary-compactional and secondary tectonic components. It is characterized by (i) predominantly oblate magnetic susceptibility anisotropy ellipsoids, (ii) low anisotropy (P′ mostly <1.1) and low magnetic susceptibility (<ca. 10 -7 m 3 kg -1) contributed mainly by paramagnetic and diamagnetic minerals and (iii) WNW-ESE magnetic lineations subparallel to the fold axes/bedding strikes/thrust front, and hence normal to the direction of palaeotectonic compression. Thermal demagnetization of single core specimens from 103 levels across 1120 m of the lower part revealed a characteristic remanence of the high unblocking temperature (> 600 °C) in hematite. Remanence ratios derived from demagnetization data allowed the first-order estimation of remanence contributions from magnetic minerals (goethite, maghemite, magnetite and hematite), and discrimination of rockmagnetic zones correlatable with distinct lithofacies, which will facilitate objective mapping. We correlated a magnetic polarity sequence, constructed from normal and reverse polarity directions from 77 levels that passed the reversal test and represented primary remanences, with the standard geomagnetic polarity timescale to constrain the depositional age between ca. 13.2 Ma (base of Chron C5AAN, 13.015-13.183 Ma) and the middle of Chron C5n.2n (9.987-11.040 Ma). We calculated the sediment accumulation rate for polarity zones from the chronologically better constrained part below Chron C5n.2n (i.e. below 11.040 Ma) to be 25-61 cm kyr -1 (average, 39 cm kyr -1), which is consistent with the value of 32-50 cm kyr -1 reported from Siwaik sections in Nepal. The notable increase in accumulation rate after 12.1 Ma probably reflects the peak of the earlier phase of uplift and/or unroofing of the Himalayan source region followed by rapid accumulation in the foredeep, and a link to monsoon initiation/intensification. Compared to the expected remanence from the latest APWP for the Indian Plate 10-13 Ma, the best-defined mean (351.8°/20.9°) is rotated anticlockwise by 9.2° and records an inclination shallowing of 25°. Constraining the base of the Tinau Khola north section to 13.2 Ma (i.e. older than the Tinau Khola south by 1.7 Myr) should open up new horizons for multidisciplinary and multiproxy research targeting geotectonic/climatic/environmental palaeoreconsructions of Himalaya-wide events. c 2012 The Authors Geophysical Journal International c 2012 RAS.
  • Gautam Pitambar, Sakai Tetsuya, Paudayal Khum Narayan, Bhandari Sudarshan, Gyawali Babu Ram, Gautam Chinta Mani, Rijal Moti Lal
    Bulletin of the Department of Geology Bulletin of the Department of Geology 12 17 - 28 1996-3491 2009年 [査読有り][通常論文]
     
    A 28-m thick exposure of the younger stage deposits of Kathmandu Valley fluvio-deltaic deposits at Dhapasi has been studied for magnetic susceptibility (MS), remanent magnetization (RM), grain size characteristics of fine-grained sediments, and sedimentary fabric by anisotropy of magnetic susceptibility (AMS) . In situ volume MS (κ; in 10^[-3] SI) of the natural sediments ranges from 0.001 to 0.15, with lower range (<0.02) restricted to quartz-rich coarse sand, whereas the uppermost 20-cm thick section affected by anthropogenic activity exhibits enhanced range (0.15-2). RM of specimens from...
  • ゴータム ピタンバル
    Journal of Nepal Geological Society 38 39 - 48 2008年 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Magnetic fabric data based on the anisotropy of magnetic susceptibility (AMS) of the sediments constituting the Siwalik sections (Karnali R., Amilia–Tui Road, Surai R., Tinau R., and Rato R.) in Nepal have been analysed for the variability of magnetic lineation and the implications to the time-space evolution of the stress field in this region during the last 16 myrs. This involved compilation of (i) the magnetic polarity data that constrain the depositional age of the Nepalese Siwaliks to ca. 16 to 1 Ma, and (ii) the declination of characteristic magnetic remanence to reveal the relative tectonic rotations (17° CCW at Butwal to 9° CW at Amilia). The magnetic fabric, defined mainly by alignment of paramagnetic minerals, corresponds to an oblate ellipsoid with foliation parallel to bedding plane, implying a sedimentary-compactional origin. The magnetic lineations show well defined clusters (confined in or close to the bedding plane). Being subparallel to the fold axes/bedding strikes/thrust fronts, these lineations are assumed to originate from a secondary mild deformation process related to the compression tectonics in the Siwalik foredeep and therefore correspond to the active direction of the minimum principal horizontal stress active during foredeep deposition. Hence, the direction of compression is orthogonal to the mean lineation. The compression direction in the palaeogeographic coordinates can be obtained by introducing an additional correction for the tectonic rotation about the vertical, using the palaeomagnetic declination. Available AMS-based lineations, corrected for rotation about vertical using palaeomagnetic declinations, reveal that the compression direction in the Himalayan foreland remained in general N to NNE with significant deviations in its far western part, in particular around the Amilia–Tui section where the direction was N58o E.
  • Gautam, P.; Takashima, R.; Dick, M.H.; Kanamatsu, T.; Rijal, M.L.; Nishi, H.; Mawatari, S.F.;
    Origin and Evolution of Natural Diversity: Proceedings of the International Symposium, The Origin and Evolution of Natural Diversity, held from 1-5 October 2007 in Sapporo, Japan 101 - 107 2008年 [査読有り][通常論文]
  • Ishimura, T.; Dick, M.H.; Takashima, R.; Hirose, M.; Gautam, P.; Nishi, H.; Tsunogai, U.;
    Origin and Evolution of Natural Diversity: Proceedings of the International Symposium, The Origin and Evolution of Natural Diversity, held from 1-5 October 2007 in Sapporo, Japan 109 - 114 2008年 [査読有り][通常論文]
  • Takashima, R.; Dick, M.H.; Nishi, H.; Mawatari, S.F.; Nojo, A.; Hirose, M.; Gautam, P.; Nakamura, K.; Tanaka, T.;
    Origin and Evolution of Natural Diversity: Proceedings of the International Symposium, The Origin and Evolution of Natural Diversity, held from 1-5 October 2007 in Sapporo, Japan 75 - 82 2008年 [査読有り][通常論文]
  • The origin and evolution of natural diversity
    Gautam, P.
    Episodes 31 (4) 444 - 445 07053797 (ISSN) 2008年 [査読無し][通常論文]
  • Goddu, S.R.; Appel, E.; Gautam, P.; Oches, E.A.; Wehland, F.;
    Journal of Asian Earth Sciences 30 (1) 73 - 81 2007年 [査読有り][通常論文]
  • Takashima Reishi, Gautam Pitambar, Nishi Hiroshi
    Scientific Drilling Journal Scientific Drilling Journal 2 (0) 50 - 51 1816-3459 2006年03月 [査読無し][通常論文]
  • Gautam Pitambar, Blaha Ulrich, Appel Erwin
    Atmospheric environment Atmospheric environment 39 (12) 2201 - 2211 1352-2310 2005年04月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Dust-loaded tree leaves from Kathmandu have been analyzed for magnetic susceptibility (χ) and heavy metal (HM) contents. For 221 samples of leaves of cypress (mainly Cupressus corneyana), silky oak (Grevillea robusta) and bottlebrush (Callistemon lanceolatus), χ has a range of (0.01-54)×10^[-8] m^3 kg^[-1] with a median of about 10.0×10^[-8] m^3 kg^[-1]. Trees situated close to the busy road intersections, near the main bus station and sectors of roads with steep slope yield elevated susceptibility. Chemical analysis of 20 samples of varying susceptibility by atomic absorption spectrometry ...
  • Gautam, P.; Blaha, U.; Appel, E.;
    Island arc 14 (4) 424 - 435 2005年 [査読有り][通常論文]
  • Gautam, P. and Watanabe, T. and Nishi, H. and Yasunari, T.
    Island Arc 14 (4) 295 - 296 1038-4871 2005年 [査読無し][通常論文]
     研究論文(学術雑誌)
  • 19th Himalaya-Karakoram-Tibet Workshop
    Pitambar, G. and Kazunori, A.
    Episodes 28 (1) 53 - 54 07053797 (ISSN) 2005年 [査読無し][通常論文]
  • E. Schill, E. Appel, C. Crouzet, P. Gautam, F. Wehland, M. Staiger
    Special Paper of the Geological Society of America 383 73 - 85 00721077 2004年12月 [査読有り][通常論文]
     
    Late orogenic rotations and tilting along a N-S transect at ∼84.5 °E crossing the Manaslu leucogranite, and earlier results from the western and central part of the Himalaya, are used to investigate the existence of oroclinal bending and ramping on the Main Central Thrust. Tectonic deformation is deduced from secondary remanent magnetization residing in pyrrhotite, which formed during metamorphism. Remanence acquisition is related to the last cooling event through 325 °C (Curie temperature of pyrrhotite). Local and regional thermo-chronological constraints suggest Oligocene to Pliocene acquisition ages. In the south, similar inclinations of the Greater Himalayan Sequence and Lesser Himalayan Sequence across the Main Central Thrust result in a mean southward tilting of ∼15°. This is in contradiction to the existing model of Main Central Thrust ramping; it favors the interpretation of duplex structures. In the north of the transect significant clockwise rotations of 47° ± 8° with respect to the Indian plate are observed in the Tethyan metasediments north of the South Tibetan detachment system. This result coincides with earlier data from the Tethyan sedimentary series in the central Himalaya. Further to the south, in the Greater Himalayan sequence and Lesser Himalayan sequence, clockwise rotations are distinctly smaller (∼10°) and rather consistent within these units. In contrast to the western Himalayas, where paleomagnetic results indicate oroclinal bending around the syntaxis, the large late-orogenic clockwise rotation in the hanging wall of the South Tibetan detachment system in the investigated area and the increasing clockwise rotations across the central Himalayas from west to east argue against oroclinal bending of the whole Himalayan arc. The rotation angle of ∼10°, observed south of the South Tibetan detachment system, may be related to uniform rotational shortening at the northern margin of India, which must have occurred south of the Lesser Himalayan sequence. However, the large lateorogenic clockwise rotation observed in the Tethyan sedimentary series is more likely related to the eastward extrusion of the Tibetan plateau. © 2004 Geological Society of America.
  • Gautam Pitambar, Blaha Ulrich, Appel Erwin, Neupane Ghanashyam
    Physics and chemistry of the earth Physics and chemistry of the earth 29 (13) 973 - 984 1474-7065 2004年 [査読有り][通常論文]
     
    The Kathmandu Valley is a bowl-shaped intermontane basin, which occupies an area of 583 km2 in the heart of the Himalayas, with its floor at ca. 1400 m and the surrounding mountains attaining a height of 2000-2800 m. It is inhabited by ca. 1.5 million people, concentrated mostly in three cities, Kathmandu, Patan and Bhaktapur. Due to rapid but uncontrolled urbanization and factors such as traffic movement, emissions from brick-kilns, cement factory, other industrial activities, waste disposal and biomass burning, environmental pollution has been constantly increasing adversely affecting lan...
  • Crouzet, C. and Gautam, P. and Schill, E. and Appel, E.
    Tectonophysics 377 (1-2) 179 - 196 0040-1951 2003年 [査読有り][通常論文]
     
    A palaeomagnetic study has been carried out in the Tethyan Himalaya (TH; the northern margin of Greater India). Twenty-six palaeomagnetic sites have been sampled in Triassic low-grade metasediments of western Dolpo. Two remanent components have been identified. A pyrrhotite component, characterized by unblocking temperatures of 270-335 degreesC, yields an in situ mean direction of D = 191.7degrees, I = -30.9degrees (k=29.5, alpha(95)=5.7degrees, N=23 sites). The component fails the fold test at the 99% confidence level (k(in) (situ)/k(bed) = 6.9) and is therefore of postfolding origin. For reason of the low metamorphic grade, this pyrrhotite magnetization is believed to be of thermo-chemical origin. Geochronological data and inclination matching indicate an acquisition age around 35 Ma. The second remanence component has higher unblocking temperatures (>400 degreesC and up to 500-580 C range) and resides in magnetite. A positive fold test and comparison with expected Triassic palaeomagnetic directions suggest a primary origin. The postfolding character of the pyrrhotite component, and its interpreted age of remanence acquisition, implies that the main Himalayan folding is older than 35 Ma in the western Dolpo area. This study also suggests that the second metamorphic event (Neo-Himalayan) was more significant in the Dolpo area than the first (Eo-Himalayan) one. A clockwise rotation of 10-15degrees is inferred from the pyrrhotite component, which is compatible with oroclinal bending and/or rotational underthrusting models. This rotation is also supported by the magnetite component, indicating that no rotation of the Tethyan Himalaya relative to India took place before 35 Ma. (C) 2003 Elsevier B.V. All rights reserved.
  • Schill, E. and Appel, E. and Godin, L. and Crouzet, C. and Gautam, P. and Regmi, K. R.
    Tectonophysics 377 (1-2) 197 - 209 0040-1951 2003年 [査読有り][通常論文]
     
    Secondary magnetic remanences residing in pyrrhotite and anisotropy of magnetic susceptibility (AMS) were studied in low-grade metamorphic carbonates of the Tethyan Himalaya in Nar/Phu valley (central Nepal) and used for interpretation of tectonic deformations. The characteristic remanence (ChRM) is likely of thermomagnetic origin related to post-peak metamorphic cooling occurring after the Eohimalayan phase (35-32 Ma). The. ChRM postdates small-scale folding (main Himalayan folding F l and F2) as shown by a negative fold test of site mean directions at 99% confidence level, and has been probably acquired between 32 and 25 Ma. Late-orogenic long-wavelength folding associated with the Chako antiform (CA) is recorded by the spatial dispersion of ChRM directions and the distribution of the main axes of the AMS tensor. The mean tilting of the ChRM direction since remanence acquisition (approximate to 20-30degrees) approximately coincides with the tilting of the CA (31degrees) at the study area indicating that the pyrrhotite remanence predates the CA (CA formed at < 18 Ma according to preliminary U/Pb dating). However, comparison of tilt angles of remanence directions and AMS tensor axes suggests that remanence acquisition was not completed before the onset of the CA formation. This could imply a younger age (Early Miocene or even younger) of the ChRM. Using the distribution of remanence directions along a small-circle as well as the distribution of AMS tensor axes, a clockwise mean rotation of 16degrees is obtained for a remanence age of approximate to 30: Ma. An Early.Miocene remanence age would not change this result substantially. Compilation of rotations in the Tethyan Himalaya deduced from secondary pyrrhotite remanences reveals an increasing clockwise rotation from the Hidden valley in the W to the Shiar valley in the E (approximate to 150 km distance), incompatible with an oroclinal bending model. (C) 2003 Elsevier B.V. All rights reserved.
  • Schill, E. and Appel, E. and Gautam, P.
    Journal of Asian Earth Sciences 20 (3) 195 - 201 1367-9120 2002年 [査読有り][通常論文]
     
    In Mesozoic metacarbonates of the Tethyan Himalayas (Shiar Khola area, Central Nepal) two characteristic remanent magnetisations (ChRM(1) and ChRM(2)) were identified by their unblocking temperature spectra. The ChRM(1) is carried by pyrrhotite (unblocking temperature: 270-360 degreesC) and the ChRM(2) by magnetite (unblocking temperature spectra: 430-580 degreesC). The temperature-related formation of pyrrhotite at the expense of primary magnetite during low-grade metamorphism in marly carbonates allows the determination of thermal gradients by the pyrrhotite/magnetite ratio. This new method can be used as a geothermometer for T less than or equal to 300 degreesC in low-grade metamorphic carbonates, where other methods are not available. This method is applied for the first time in the Tethyan Himalayas of Central Nepal. In the Shiar Khola valley, systematic variations in the ferrimagnetic content of the metacarbonates along an E-W profile were detected by the ratio of remanence intensity of pyrrhotite to magnetite, derived from natural remanent magnetisation (R-PYR/MAG) and saturation magnetisation (S-PYR/MAG). Over a stretch of 10 km the R-PYR/MAG and S-PYR/MAG increase from W to E from similar to0.42 to similar to0.91 and similar to0.48 to similar to1.0, respectively. Based on temperature estimates, the eastern part experienced upper anchizone-epizone (similar to 250-300 degreesC) conditions, while the western part underwent only diagenesis (similar to 200 degreesC). The temperature gradient and the temperature ranges suggested are consistent with the findings of the calcite twin lamellae geothermometry which is a non-magnetic method. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Schill, E. and Appel, E. and Gautam, P. and Dietrich, P.
    Journal of Asian Earth Sciences 20 (3) 203 - 210 1367-9120 2002年 [査読有り][通常論文]
     
    Palaeomagnetic measurements were carried out on low-grade metamorphic carbonates, of Mesozoic age from the Shiar area (85.1 degreesE, 28.6 degreesN) of the Tethyan Himalaya (TH) in north central Nepal. Two characteristic remanence components carried by pyrrhotite (ChRM(1)) and magnetite (ChRM(2)) could be identified by their unblocking temperature spectra of 270-340 and 430-580 degreesC, respectively. Fold tests are not significant, due to the uniform bedding of all sites. However, according to results from other areas:of the TH, the pyrrhotite component has been probably acquired as a secondary (p)TRM during exhumation and cooling; thus the age of remanence acquisition can be related to the last cooling event (25-17 Ma in the surrounding areas), The inclination of the magnetite component matches the value expected from the Indian APWP. This may the primary origin of the ChRM(2). Pyrrhotite site-mean directions show a small-circle distribution, with a best fit parallel to the N-S direction. Backtilting to the expected inclination (I-exp) by intersection of the remanence small-circle with the small-circle of constant I-exp yields a clockwise block rotation of 30-35 degrees with respect to the Indian Plate. Characteristics of the pyrrhotite component (small-circle distribution of site-means, secondary origin, (p)TRM with unblocking temperatures below about 300 degreesC), allow the interpretation of the chronologic order of the thermo-tectonic history: (i) an earlier main folding phase at elevated temperatures (ii) a later event of cooling through about 300 degreesC coinciding with the acquisition of ChRM(1); (iii) clockwise block rotations with respect to the Indian Plate and (iv) long-wave folding as the youngest tectonic event. (C) 2002 Elsevier Science Ltd. All rights reserved.
  • Schill, E. and Crouzet, C. and Gautam, P. and Singh, V. K. and Appel, E.
    Earth and Planetary Science Letters 203 (1) 45 - 57 0012-821X 2002年 [査読有り][通常論文]
     
    In metacarbonates of the Lesser (LH) and Tethyan (TH) Himalayas of Kumaon/Garhwal (N-India) characteristic remanent magnetisations carried by pyrrhotite (unblocking temperatures: 250-330degreesC) and magnetite (demagnetising spectra: 15-50 mT) have been identified. Negative fold tests indicate remanence acquisition after the main folding phase, which is of short-wavelength character and occurs during the early orogenese of the Himalayas. A thermal or thermochemical origin of magnetisation is likely and the age of remanence acquisition is indicated to be about 40 Ma by K-40/Ar-39 cooling and Ar-40/Ar-39 crystallisation ages. In the Kumaon LH a long-wavelength tilting is indicated by a distribution of the remanence directions along a small-circle in N-S direction. Steepening of the remanence directions in the TH related to ramping on the Main Central Thrust (MCT) was not observed, in contrast to other related studies. In the Alaknanda valley of LH a 38 +/- 8 Ma age of remanence acquisition is supported by comparison of observed inclinations to the apparent polar wander path of India. Clockwise rotation of 20.3 +/- 11.7degrees (LH/Alaknanda valley) and 11.3 +/- 8.5degrees (TH) with respect to the Indian plate is observed, indicating that there is no significant evidence for rotational shortening along the MCT since about 40 Ma. Our results suggest that most of rotational underthrusting and oroclinal bending has not been accommodated by the MCT, but by the main thrusts south of it. The latest Miocene/Pliocene age of the Main Boundary Thrust indicates that oroclinal bending is a late-orogenic process. (C) 2002 Elsevier Science B.V. All rights reserved.
  • Magnetostratigraphic evidence for the occurrence of pre-Brunhes (> 780 kyr) sediments in the northwestern part of the Kathmandu Valley, Nepal
    ゴータム ピタンバル
    Journal of Nepal Geological Society 25 99 - 109 2001年 [査読有り][通常論文]
     研究論文(学術雑誌)
  • Crouzet, C. and Stang, H. and Appel, E. and Schill, E. and Gautam, P.
    Geophysical Journal International 146 (3) 607 - 618 0956-540X 2001年 [査読有り][通常論文]
     
    Low-grade metacarbonates from the Tethyan Himalaya were sampled for palaeomagnetic studies in Hidden Valley (Central Nepal). The remanence is carried by pyrrhotite, evidenced by thermomagnetic runs of susceptibility (Hopkinson peak at similar to 300 degreesC), alternating field demagnetization, isothermal remanent magnetization acquisition and subsequent thermal demagnetization. The palaeomagnetic directions reflect a Tertiary overprint after the main folding event, probably synchronous with the metamorphism. Normal and reverse remanence directions were separated and vary with altitude. It is also possible to retrieve several antiparallel components versus temperature during thermal demagnetization of a single sample. At higher altitudes (4920-5500 m), the first component recorded is reverse (R-1). At a lower temperature a normal component can be extracted (N-1). For sites sampled at lower altitudes (4700-4900 m), the high-temperature reverse component disappears but a medium-temperature reverse component (R-2) demagnetized in a narrow temperature range can be identified in between two normal components (N-1 at high temperature and N-2 at low temperature). At the lowest altitudes (4450-4700 m), only a normal component (N-2) appears. The occurrence of successive normal and reverse polarities in one sample is interpreted as the record of successive reversals of the geomagnetic field during the post-metamorphic Tertiary cooling of the studied area. The polarity versus attitude function is a powerful argument for a thermomagnetic origin of the magnetization. No obvious rotations around a vertical axis with respect to the stable Indian plate are evidenced for the Tertiary. However, the inclination is not consistent with the expected inclination. Main Central Thrust ramping can be invoked to explain our observations. R-1, N-1 and N-2 inclinations are slightly different and their tendency is consistent with tilting towards the north during magnetization acquisition. The minimum total amount of such tilting is around 25 degrees. Accurate geochronological data from the Tethyan Himalaya would be of a great help for better resolution.
  • Schill, E. and Appel, E. and Zeh, O. and Singh, V. K. and Gautam, P.
    Tectonophysics 337 (1-2) 1 - 21 0040-1951 2001年 [査読有り][通常論文]
     
    The total amount of crustal shortening within the Indian plate includes straight forward and rotational shortening. The complex tectonic history of the western Himalaya impedes a direct observation of rotational shortening between India and its northern margin. A combination of palaeomagnetic results and tectonic structures along a similar to 300 km NW-SE section, from NW-Zanskar (33.9 degreesN, 76.5 degreesE) to Malari (30.0 degreesN, 79.6 degreesE) in northern India, enable a separation of rotations on different scales, correction of the observed rotations, and quantification of uniform rotational shortening. New palaeomagnetic results from metacarbonates of the Tethyan Himalaya in Sarchu, Losar, and Spiti and earlier studies from NW-Zanskar and Malari reveal a characteristic remanent magnetisation carried by pyrrhotite (unblocking spectrum: 250-330 degreesC). Negative fold tests (99% level) indicated remanence acquisition after the main folding of the Himalaya. The formation of pyrrhotite during thermal events (T > 200 degreesC) suggests a remanence acquisition related to exhumation and cooling. Temperatures of about 200-300 degreesC indicate a thermochemical remanence acquisition with an Eohimalayan age, dated in two areas by K-40/Ar-39 techniques on illites. The resulting rotation angles in respect to stable India show an 'anomalous' counterclockwise rotation in NW-Zanskar and a trend of decreasing clockwise rotations to the SE. These variations may be attributed to meso-scale (similar to 100 kin) tectonic features and oroclinal bending. For the first time block rotations with respect to stable India are separated into local, meso-scale and regional significant ones. After elimination of local and meso-scale effects, using structural analysis of late orogenic features, modelled rotations due to oroclinal bending were subtracted. Regionally significant rotations of 0-20 degrees clockwise are interpreted to be caused only by uniform rotational underthrusting. (C) 2001 Elsevier Science B.V. All rights reserved.
  • Gautam Pitambar, Fujiwara Yoshiki
    Geophysical journal international Geophysical journal international 142 (3) 812 - 824 0956-540X 2000年09月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    The remanent magnetization of siltstones and sandstones sampled at 476 levels/sites throughout a 3560 m thick molasse sequence belonging to the Siwalik Group (0-2015 m: Lower; 2015-3560 m: Middle) has been studied by stepwise thermal demagnetization. This section is exposed along the Karnali River in Nepal. The natural remanent magnetization (NRM) usually consists of two components: a viscous or thermoviscous component of recent field origin, and an ancient characteristic component (ChRM). The former component is of normal polarity and resides either in goethite (unblocking temperature < 15...
  • GAUTAM Pitambar, HOSOI Azumi, REGMI Kamal Raj, KHADKA Dharma Raj, FUJIWARA Yoshiki
    Earth, planets and space Earth, planets and space 52 (5) 337 - 345 1343-8832|1880-5981 2000年 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Sandstones and siltstones collected from the Siwalik molasse sequence (~16 to 5 Ma) of the Karnali river section have been studied for their magnetic properties. Behavior of the specimens during demagnetization (of theNRMand IRM) and magnetic susceptibility vs. temperature data suggest that goethite, maghemite/magnetite, and hematite are the main magnetic minerals in the section. Goethite, carrying a recent component, is the dominant magnetic mineral in the fine-grained lithologies from the lower part. Maghemite and magnetite, which also carry a secondary remanence, occur in the sandstones...
  • Gautam, P. and Pant, S. R. and Ando, H.
    Journal of Applied Geophysics 45 (2) 97 - 110 0926-9851 2000年 [査読有り][通常論文]
     
    Electrical resistivity (sounding with Schlumberger array and dipole-dipole imaging) and natural gamma ray intensity measurements were made over the karst features (subsurface flow-channels, solution cavities, sinkholes) in the Pokhara valley, central Nepal. In the Powerhouse area, the upper 60-80 m section of the basin-filling Quaternary sediments is represented by layered elastic sediments (gravel, silt, clay) that are represented by KQ-type (rho(1) < rho(2) > rho(3) > rho(4)) electrical sounding (ES) curves. The true electrical resistivity of the layers has a wide range of variation (a few hundreds to several tens of thousands of Omega m) such that it is possible to determine both the vertical and lateral subsurface geological variations by integrating the electrical resistivity profiling and sounding techniques. Total gamma ray intensity profiles measured over various karstified locations reveal significant anomalies (up to 100 counts per second, cps) over the known or unknown subsurface openings. In the Powerhouse area, presence of a network of at least three linear NNE-SSW oriented subsurface channels, made by past and present underground flow-channels, is inferred. In interpreted electrical image profiles, contours of elevated resistivity reflect the cross-sectional geometry of cavities. The gamma-ray method is sensitive to near-surface cavities while the electrical image effectively locates the void spaces at intermediate (up to 5-20 m) depths. An exploration program involving rapid radiometric mapping followed by selective electrical imaging is recommended for future exploration of karst-prone areas in the valley. (C) 2000 Elsevier Science B.V. All rights reserved.
  • Radiometric and geoelectric response of karst structures in Mahendra and Chamero Caves, Pokhara Valley, Nepal
    Gautam, P. and Pant, S. R. and Ando, H. and Wagle, R. N.
    Journal of Nepal Geological Society 22 (Special Issue, International Symposium on Engineering Geology, Hydrogeology, and Natural Disasters with Emphasis on Asia: 28-30 September 1999, Kathmandu, Nepal) 179  2000年 [査読有り][通常論文]
     研究論文(学術雑誌)
  • Gautam Pitambar, Rösler Wolfgang
    Journal of Asian Earth Sciences Journal of Asian Earth Sciences 17 (5/6) 659 - 682 1367-9120 1999年10月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Magnetostratigraphic research, undertaken within the past 15 years in the Siwaliks distributed along 400 km of the Sub-Himalaya in central Nepal, has proved that the sediments possess highly reliable hematite-based primary detrital remanent magnetization suitable to determine depositional chronology. In order to bring out the polarity sequences in a common chronological frame, all available data are newly correlated to the latest global magnetic polarity time scale of Cande and Kent (1995). Chronological data presented are referred in relation to the diverse lithological nomenclature to the...
  • Preliminary palaeomagnetic results from medium-grade metacarbonates of the Lesser Himalaya
    Schill, E.; Appel, E.; Gautam, P.; Singh, VK;
    Journal of Nepal Geological Society 18 205 - 215 1998年 [査読有り][通常論文]
  • Gautam, Pitambar; Sharma, Madhav Prasad; Dhakal, Subodh
    Journal of Nepal Geological Scoiety 18 71 - 83 1998年 [査読有り][通常論文]
     研究論文(学術雑誌)
  • Magnetic fabric of Siwalik Group sediments of Tinau Khola section, west central Nepal
    Gautam, P. and Pant, S. R.
    Bulletin of the Department of Geology, Tribhuvan University 5 21 - 36 1996年 [査読有り][通常論文]
  • Paleomagnetism and petrochemistry of the Dowar Khola volcanics, central Nepal sub Himalaya
    Gautam, P. and Upreti, B. N. and Arita, K.
    Journal of Nepal Geological Society 11 179 - 195 1995年 [査読有り][通常論文]
  • Gautam Pitambar, Appel Erwin
    Geophysical Journal International Geophysical Journal International 117 (1) 223 - 234 0956-540X 1994年04月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Remanent magnetization of sandstones sampled at 127 levels/sites throughout a 1710 m thick Siwaliks molasse sequence exposed along the Tinau Khola river in Nepal has been studied using thermal demagnetization. the magnetic remanence consists of: a secondary low-temperature component of normal polarity, unblocked mostly below 400-500℃. close to the present-day field, and a high-temperature characteristic remanence (ChRM) unblocked mostly between 600 and 685℃, represented by both normal and reverse polarities. Demagnetization behaviour and isothermal remanence acquisition indicate that the se...
  • Fujiwara Yoshiki, Gautam Pitambar, Yoshida Mitsuo, Katsui Yoshio
    北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 23 (2) 167 - 174 0018-3474 1992年08月 [査読有り][通常論文]
     
    The magnetic remanence of the andesitic pumice of the Nevado del Ruiz 1985 eruption has the multi-component nature. The major normal component behavior is due to the titanomagnetite phase with variable chemistry. The major reverse component has a peak demagnetization and acquisition range between 200°-225℃ but no such mineral phase could be detected. The titanomagentite phase contributes to the major normal component and has probably no relation to the reverse magnetization.
  • Zircon and apatite fission track dating of the Ampipal alkaline massif, the Nepal Lesser Himalaya
    Gautam, P.; Koshimizu, S.;
    Journal of Nepal Geological Society 7 1 - 8 1991年 [査読有り][通常論文]
  • Arita Kazunori, Gautam Pitambar, Ganzawa Yoshihiro
    北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 22 (4) 519 - 528 0018-3474 1990年08月 [査読無し][通常論文]
     
    K-Ar ages were newly determined on biotite from a pelitic gneiss and on hornblende from a calcareous gneiss both from the Higher Himalayas in Nepal. The corresponding ages, 56.7±2.8 Ma and 61.5±3.1 Ma, respectively, are quite old compared with their fission-track ages. We made a synthesis of the various isotopic ages from the Nepal Himalayas available so far, and attempted an analysis on the age versus closure temperature basis. The findings suggest that the Higher Himalayas have undergone two major reheating episodes, during the Himalayan orogeny, which are reflected in two different cooli...
  • Gautam Pitambar
    北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 22 (4) 591 - 609 0018-3474 1990年08月 [査読有り][通常論文]
     
    Remanent magnetization of the low-grade metasediments (272 specimens/131 samples from 26 sites), which constitute the Nawakot and Kathmandu Complexes in the northwestern part of the Mahabharat synclinorium, is described. Alternating field (AF) and thermal (TH) demagnetization experiments reveal stable secondary magnetization resting in hematite and represented by normal and reverse polarities. The secondary remanence is of prefolding origin in the rocks from the Nawakot Complex while it post-dates major folding in those from the Kathmandu Complex. The directions are consistent with near-equ...
  • 八幡 正弘, 五十嵐 八枝子, Gautam Pitambar, 和田 信彦
    地球科學 地球科學 43 (5) 261 - 276 03666611 1989年09月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    Lacustrine deposits and terrestrial volcanic products of Pliocene to Middle Pleistocene age are widely distributed in the eastern part of Toya Lake. Based on some unconformities, Pliocene and Pleistocene deposits are divided into the following major divisions: the Kitayuzawa Formation, the Rerukomabetsu Formation, the Andesite Member, the Sohbetsu pumice flow deposit and the Takinoue welded tuff, the Kimobetsu welded tuff, and the Tokushunbetsu clay member. Lower to Middle Pliocene deposits of the Kitayuzawa Formation were accumulated in two polygonal collapse sub-basins, which form the so-...
  • Gautam Pitambar
    北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 22 (3) 467 - 487 0018-3474 1989年02月 [査読無し][通常論文]
     
    Magnetic properties of a total number of 117 samples collected with an aim of preliminary paleomagnetic study from 26 sites in the Tansen area were investigated. Measurements of natural remanent magnetization (NRM) showed that only 11 sites (61 samples), which are represented by olive green sandstones and siltstones and redbeds (red-colored shale, sandstone and iron-rich rocks) possess magnetizations strong enough to be analyzed for stability of the remanence by alternating field (AF) and thermal (TH) demagnetization techniques. Demagnetization behavior, isothermal remanent magnetization (I...
  • Gautam, Pitambar
    Journal of Geomagnetism and Geoelectricity 41 (1) 101 - 117 0022-1392 1989年 [査読有り][通常論文]
  • YOSHIDA M, GAUTAM P
    Proc Indian Natl Sci Acad Part A 54 (3) 410-417  0370-0046 1988年05月 [査読有り][通常論文]
     研究論文(学術雑誌)
  • ON THE SECONDARY MAGNETIZATION OBSERVED IN THE NAWAKOT COMPLEX ROCKS, MALEKHU AREA, CENTRAL NEPAL
    GAUTAM, P.; YOSHIDA, M.;
    Journal of Nepal Geological Society 5 1  1988年 [査読有り][通常論文]
  • Gautam Pitambar
    北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 北海道大学理学部紀要 = Journal of the Faculty of Science, Hokkaido University. Series 4, Geology and mineralogy 22 (2) 259 - 275 0018-3474 1987年08月 [査読有り][通常論文]
     研究論文(学術雑誌) 
    For a preliminary paleomagnetic research on Late Precambrian to Early Paleozoic rocks in the Tansen area (West Central Nepal) carbonate, sandstone, quartzite and slate were collected from 30 sites at 4 localities. Detailed analyses of magnetic remanence were made using alternating field and thermal demagnetization techniques. Most of the specimens were found to be weakly magnetized (intensities of 10^-7 emu/cc, in order). Three magnetic components have been distinguished: (1) a predominant secondary component of recent origin, which represents a larger portion of the magnetization intensity...

書籍

  • Origin and Evolution of Natural Diversity: Proceedings of the International Symposium, held from 1-5 October 2007 in Sapporo, Japan (Edited by Hisatake Okada, Shunsuke F. Mawatari, Noriyuki Suzuki, Pitambar Gautam)
    ゴータム ピタンバル (担当:共編者範囲:Geosciences and biosciences)
    Hokkaido University 2008年03月 ISBN: ISBN: 978-4-9903990-0-9 255+ 
    International Symposium "The Origin and Evolution of Natural Diversity". 1--5 October 2007. Sapporo, Japan. Organized by 21st Century Center of Excellence (COE) Program, "Neo-Science of Natural History - Origin and Evolution of Natural Diversity", in association with the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Japan Drilling Earth Science Consortium (J-DESC), Botanical Society of Japan, Hokkaido University Museum, Palaeontological Society of Japan, Union of Japanese Societies for Systematic Biology and Zoological Society of Japan.
  • Uplift of the Himalaya-Tibet region and the Asian monsoon-geological, geomorphic and environmental consequences
    ゴータム ピタンバル (担当:共編者)
    John Wiley & Sons, Inc. 2005年12月 
    This thematic section contains 11 contributions based on presentations given at a special session entitled ‘Uplift of Himalaya–Tibet Region and Asian Monsoon: Interactions among Tectonic Events, Climatic Changes and Biotic Responses during Late Tertiary to Recent Times’ of the This thematic section contains 11 contributions based on presentations given at a special session entitled ‘Uplift of Himalaya–Tibet Region and Asian Monsoon: Interactions among Tectonic Events, Climatic Changes and Biotic Responses during Late Tertiary to Recent Times’ of the 19th Himalaya–Karakoram–Tibet (HKT) Workshop in Niseko, Japan, in 2004. It is a cross-section of current multidisciplinary research in earth and environmental sciences dealing with the Himalayas and adjacent regions. A wide range of subjects is covered, including regional geology and paleontology, glaciology and geomorphology, environmental pollution and natural hazards, and climate. We hope that bringing these subjects together in one thematic issue will help readers understand a wide variety of natural phenomena and their records as manifestations of complex interactions between tectonic processes causing the uplift of the Himalayan region and climate, in particular the Asian monsoon. The special session was planned with collaboration and support from two Japanese 21st Century Center of Excellence (COE) Projects: ‘Neo-Science of Natural History – Origin and Evolution of Natural Diversity’ (leader: H. Okada) at Hokkaido University and ‘Dynamics of the Sun–Earth–Life Interactive System’ (leader: T. Yasunari) at Nagoya University. The first three papers are devoted to traditional geological research across the central part of the Himalayas in various geotectonic settings: high Himalaya (the summit region of Mount Everest, Nepal), the Himalayan foothills (Karnali River Basin, Nepal) and the intermountain basin (Kathmandu Valley, Nepal). Sakai et al. precisely locate the Qomolangma detachment below the top of the world that separates the unmetamorphosed and fossiliferous summit limestone of Ordovician age from the metamorphic yellow band. The latter has chronological evidence of two phases of metamorphism (at 33.3 and 24.5 Ma) and rapid cooling (200°C/my) during the Middle Miocene (15.5–14.4 Ma). Huyghe et al. combine data on facies associations, clay minerals and isotopic abundances of the sedimentary fill of the Karnali River section, which contains the most continuous and magnetostratigraphically best-dated archive of sediments recording the post-Middle Miocene erosion of the Himalayas, and decipher the late Tertiary tectonic evolution of the Himalayan mountain range and associated climate changes. Paudayal presents pioneering work that uses scanning electron microscope observations of fossil pollen grains from the fluvio-lacustrine sediments of the Kathmandu Valley in an attempt to reconstruct past vegetation/climate conditions at ca 40 000 years bp. He suggests that the observed vegetation changes imply a decrease in altitude of at least 1000 m during the late Pleistocene. The fourth paper, by Matsuoka et al., compares the radiolarian fauna in the Xialu chert in Tibet with those from coeval formations in southwest Japan and the western Pacific and investigates their use in Mesozoic paleoceanographic reconstructions. The subsequent two papers address the geomorphologic history of the region, with a focus on glacial deposits. Kuhle gives a summary of extensive, mostly descriptive research carried out during his numerous expeditions in a broad region that he terms ‘high Asia’ (Himalayas–Karakoram–Tibet and Hindukush, as well as east Zagros and Sayans). The observations in this paper will be a valuable framework to compare with more quantitative data that needs to be accumulated in the years ahead. In contrast, Waragai's paper deals with past climatic reconstruction based on calcrete in the lateral moraine of the Batura Glacier in the Karakoram mountain range. This compact study combines field observations with quantitative data obtained by employing a variety of analytic techniques (i.e. electron probe microanalysis, X-ray diffraction, ion chromatography) to determine the mineralogy and chemistry of calcrete, glacier ice and melt water. The age of calcrete formation is estimated to be approximately 7300 years bp using accelerator mass spectrometry 14C dating. Abe et al. use the output of a numeric simulation based on the atmosphere–ocean coupled general circulation model (CGCM) and address the problem of sensitivity of the climate response in central Asia to the uplift of the Tibetan Plateau. The numeric experiments suggest that significant drying of central Asia corresponded to the period in which the Tibetan Plateau exceeded approximately half its present-day height. Quantitative data on climate change in the Himalayan region obtained through direct or indirect observations, or numeric modeling can still only provide insights into large-scale effects and further studies in this field are needed. The output of such studies will be invaluable for understanding the regional climate variability and future climate changes, as well as developing a better understanding of the interactions between tectonics and climate. Results of studies on glacial and periglacial environments and aspects of natural hazards, such as the floods generated by lake outbursts and mass movements related to freezing–thawing cycles in mountainous regions, are discussed in the next two papers. Iturrizaga explores the history of the glacial lake outbursts since the mid-nineteenth century in the Karambar Valley in Hindukush, Pakistan, based on geomorphologic field observations, study of historical records, and interviews with the local inhabitants. The author points out that there seem to be no simple logistic and technical solutions to lessen the known danger and possible disastrous impacts of spontaneous glacial lake outbursts on the ever-expanding infrastructure in the flood-prone floors of the Karambar, Ishkoman and Gilgit Valleys. Likewise, Regmi and Watanabe attempt to quantify the rate and depth of displacement of solifluction lobes in the upper slopes (altitudes exceeding 5300 m) of the Kangchenjunga area, Nepal, based on field monitoring using glass fiber tubes as well as considering parameters such as precipitation and ground temperature vs depths and ground moisture. The movements described are rather slow (a maximum of 11 mm/year); however, further studies on the wider implications of these movements for mountain ecology are needed. The last two papers address the problems of debris flows and urban environmental pollution, respectively. Adhikari and Koshimizu analyze the geological, geomorphologic, hydrologic and engineering geological data, as well as the perceptions of the local people to decipher the cause, initiation mechanism and deposition process related to the 1996 Larcha debris flow disaster caused by landslide damming of a mountain stream and its outbreak triggered by intensive rainfall. Gautam et al. demonstrate the effectiveness of combining the rock-magnetic properties (mainly the magnetic susceptibility and the saturation isothermal remanence) and the heavy metal composition of soils in the Kathmandu urban and suburban area, Nepal, for rapid quantitative and qualitative analysis of the status of environmental pollution caused by anthropogenic activities. Though described in the Nepalese context, these data have relevance to any mountain and urban settings. We hope that these papers will stimulate interest in collaborative multidisciplinary research by adapting an integrated approach to understanding the earth and environmental processes in the HKT region, rather than being constrained by the boundaries of traditional disciplines. We acknowledge the contributions and support of K. Arita, chief organizer of the HKT19 Workshop, and H. Okada (COE Leader) in holding the special session. We thank the reviewers for providing both critical reviews and constructive suggestions on the submitted manuscripts and the authors for their prompt and positive responses during their revisions. Including this multidisciplinary issue in The Island Arc would not have been possible without the close involvement of the Editor-In-Chief, S. Wallis, in both the organization and the final stages of editing.

講演・口頭発表等

  • Scientific Publications (2004-2013) From Nepal in the Web of Science  [通常講演]
    ゴータム ピタンバル
    Moving to higher ground – from open access to open science in Asia. Asia OA Meeting – Kathmandu, Nepal 2017年12月
  • A Bibliometric Survey of Scientific Publications (1980-2017) on Natural Geological Hazards in Nepal  [通常講演]
    ゴータム ピタンバル
    11th IAEG Asian Regional Conference (ARC-11) 2017年11月 
    In view of the sparse bibliometric studies on Nepal (Gautam, 2017), we present the tentative results of a bibliometric survey of 495 scientific publications dealing with natural geological phenomena (such as landslide, earthquake, karst, glacier-related flood) and their engineering geological aspects related directly or indirectly (in the context of a broader Himalaya-wide perspective) with Nepal. The Web of Science (WOS) Core Collections database modules (SCIE, SSCI, A&HCI) were used to retrieve the documents (articles, reviews, letters and notes) using a complex search strategy targeted at publications related to all possible keywords for the phenomena mentioned above, the “Engineering, Geological” WoS subject category, and relevance to Nepal as shown by the country name at least in one of the followings: title, keywords, abstract, and author addresses. Documents related to purely engineering works, landslide victories and mass movements related to politics etc. were removed by using appropriate search filters and after manual screening of the search results. A brief summary of data processed using bibliometrix (Aria and Cuccurullo, 2017) and visualization by VosViewer (Van Eck and Waltman, 2014) are presented.
  • ゴータム ピタンバル, 岡田 直資
    研究・イノベーション学会 第3 2 回年次学術大会 2017年10月 
    This study explores the utility of the KAKEN-L3 schema, based on the Grants-in-Aid disciplinary classification available in InCitesTM analytical tool since 2015, using a subset of 13,519 core journal articles and reviews published during 2009-1013 by a comprehensive Japanese research university. A qualitative comparison of the findings using the new scheme with those derived from several others (ESI 22 fields, WoS 251 categories, OECD Frascati 38 fields) and SCOPUS (27 areas, ASJC 333 categories) using partial datasets for selected department has been also given. The KAKEN-L3 schema provides new insights into the disciplinary contributions, particularly by discriminating the fundamental versus applied research as well as cross-disciplinary research of the university. Its use results in comparatively large number of documents per disciplinary category, leading to large differences in interpretation depending on the mode of counting (whole and fractional). This fact requires due consideration while using the data for benchmarking/evaluation purposes. Keywords: Bibliometry; KAKEN schema; Cross-disciplinarity; Web of Science; Scopus
  • Detection of Bibliographic Coupling Communities Using the Research Output (2004-2013) From Nepal  [通常講演]
    ゴータム ピタンバル
    6th International Congress on Advanced Applied Informatics, Hamamatsu, Japan 2017年07月 
    This study explores a country-level bibliometric analysis to extract bibliographic coupling (BC) communities as clusters of documents coupled through publications in their reference lists using the “BiblioTool” software. The 2004-2013 research output from Nepal represented by relatively small dataset of 3,011 documents (peer reviewed articles and reviews) indexed as core collections in the Web of Science (WoS) database was used. Setting a threshold of 10 documents, twenty-five BC communities, each with 12-443 documents, which provide a comprehensive picture on the research themes characterized by diverse items (keywords, subjects, journals, institutions, countries, authors, references, and title words) were discriminated. Twelve communities (i.e., 48%) deal with medical & health sciences (maternal & child health; tropical infectious diseases; cancer & cardiovascular diseases; mountain sickness; blindness) closely linked also with social aspects; 4 communities with earth, environment and biodiversity (tectonics and natural hazards; environmental pollution, remediation and conservation; wild-life preservation); 3 communities with agriculture and veterinary sciences (pathogens of major crops (maize, wheat, rice) & crop yields, plant genes, and dairy farming); 3 communities with nanomaterials and metal-alloys; 2 communities with pharmacology including ethnomedicine, and one community of 12 documents is related to galactic observations. These new results provide wider insights on the research volume & diversity, international collaboration and the contributors (academic, national & international, governmental & nonprofit agencies, etc.) engaged in research in Nepal. Keywords- bibliometrics; scientometry; research community; Web of Science; bibliographic coupling; Nepal; higher education; international co-authorship, developing country
  • Global Institution: A Novel Concept and Approach for Promoting Collaborative Research and Education  [通常講演]
    ゴータム ピタンバル
    QS-APPLE, UMAP, Malaysia 22-24-November, 2016 2016年11月 Putrajaya, Malaysia 
    This talk will introduce the concept, background and approaches behind the Global Institution for Collaborative Research and Education (GI-CoRE) established in line with the visions of the Top Global University Project at Hokkaido University. GI-CoRE currently consists of six Global Research Stations engaged in cutting-edge research areas either with already established research strengths or having new cross-disciplinary field-oriented character and potential global significance. In addition to demonstrating the bibliometric evidence to support the existence of established research strengths, the presentation will focus on how GI-CoRE will be instrumental in long-term in enhancing the image of a true global university dedicated to both research and education as well as improving our standing in word university rankings. - Promoting existing research strengths - Creating novel research areas and strengths - Targeted in strengthening both research and education capacities
  • Comparative Analysis of Scientific Publications of Research Entities Using Multiple Disciplinary Classifications  [通常講演]
    ゴータム ピタンバル
    5th IIAI International Congress on Advanced Applied Informatics (AAI 2016) 2016年07月 
    This study attempts a comparative disciplinary analysis of a Web of Science (WoS) recorded dataset (ca. 15,000 core journal articles and reviews) of real publications for 5-years period by the research departments, dedicated to natural science, technology, engineering & medical (STEM) fields, of a comprehensive university using different disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, Scopus 27 subject areas and OECD Frascati 38 Subordinate research fields. It demonstrates that assigning the publications to departments and disciplines followed by correspondence analysis and clustering of the contingency table comprising disciplinary share of publications results in enhanced understanding and visualization of the research output at different levels of disciplinary or research entities. Such exercise improves creation of publication subsets (for different research entities for use with different disciplinary schemes) for further processing, visualization and interpretation with sophisticated bibliometric/scientometric tools including the science mapping techniques. Keywords—bibliometry; science map; correspondence analysis; clustering; research field; cross-disciplinarity; co-word; co-citation
  • Deciphering the Department-Discipline Relationships within a University through Bibliometric Analysis of Publications Aided with Multivariate Techniques  [通常講演]
    ゴータム ピタンバル
    4th IIAI International Congress on Advanced Applied Informatics (AAI 2015) 2015年07月
  • The Japanese Higher Education Landscape: Recent Trends Towards Enhancing Research Capacity and Globalization  [招待講演]
    ゴータム ピタンバル
    Higher Education Planning in Asia Forum 2015  2015年03月
  • Evolution of Institutional Research Strengths: Bibliometric Appraisal and Strategic Use  [通常講演]
    ゴータム ピタンバル
    10th QS-Apple Conference 2014年11月
  • Scientific publications on Nepal (up to 2010) in the Web of Science database: A bibliometric visualization  [通常講演]
    ゴータム ピタンバル
    10th International Conference on Webometrics, Informetrics and Scientometrics & 15th COLLNET Meeting 2014 2014年09月
  • Joint Bibliometric analysis of patents and scholarly publications from cross-disciplinary projects: Implications for development of evaluative metrics  [通常講演]
    ゴータム ピタンバル
    International Social Network Conference (DISC) 2013 2013年12月
  • 研究業績分析に用いるビブリオメトリクス指標の紹介  [招待講演]
    ゴータム ピタンバル
    北海道大学附属図書館ワークショップ「ビブリオメトリクスと研究評価」 2013年09月
  • Some observations on the national recent trends and research administration at universities in Japan  [招待講演]
    ゴータム ピタンバル
    3rd Annual Scival User Conference, Bangkok  2013年07月
  • Precise magnetostratigraphy (13–10 Ma) and rock-magnetic zonation of the Siwaliks from the lower part of Tinau Khola north section, Nepal  [通常講演]
    ゴータム ピタンバル
    The 27th Himalaya-Karakoram-Tibet Workshop (HKT), Kathmandu, Nepal 2012年11月
  • Ranking and the Japanese Context  [招待講演]
    ゴータム ピタンバル
    8th QS-Apple Conference 2012年11月
  • Reflection of Cross-disciplinary Research at Creative Research Institution (Hokkaido University) in Web of Science Database: Appraisal and Visualization using Bibliometry  [通常講演]
    ゴータム ピタンバル
    7th International Conference on Webometrics, Informetrics and Scientometrics & 12th COLLNET Meeting, Istanbul 2011年09月
  • 高橋亮平, 舘卓司, 大原昌宏, 松枝大治, 馬渡峻輔, 吉田尚生, 高橋英樹, 小林快次, GAUTAM Pitambar
    資源地質学会年会講演会講演要旨集 2008年06月
  • 加藤 孝幸, 田中 耕平, 樋掛 鉄也, 斉藤 晃生, GAUTAM Pitambar.
    日本地質学会学術大会講演要旨 1998年09月
  • Paleomagnetism of some Lesser Himalayan Formations in Nepal: stratigraphic and tectonic implications  [通常講演]
    GAUTAM, P.
    International Geological Congress 1992年
  • Gautam Pitambar, Koshimizu Satoshi
    日本地質学会学術大会講演要旨 1989年04月
  • メトリクスを用いた産学連携型プロジェクトの新規プ ロジェクト評価法の開発  [通常講演]
    児玉 耕太, Gautam Pitambar, 榎本 健悟
    年次学術大会講演要旨集 
    我々は、産学連携型プロジェクトのエビデンスに基づいた新しいプロジェクト評価法を確立することを目的に研究を行った。具体的には、旧科学技術振興調整費で実施された研究課題のうち、特に科学技術の実用化、事業化を志向するような産学連携大型プロジェクトに焦点を当て、客観的根拠に基づく科学技術イノベーション政策の形成に中長期的に寄与しうる新たな解析手法やモデル分析、集計指標等の開発を目的に研究を実施した。 このような新たな解析手法を用いた上で、各事業の性格を踏まえ同様の産学連携大型プロジェクトを企画する際に参考となるような研究成果に基づく新規プロジェクト評価法を提示することにより、このようなプロジェクトの社会的波及効果の予測、問題提起や政策提言を行いたい。

その他活動・業績

  • Pitambar Gautam Scientometrics 113 1245 -1267 2017年12月 [査読無し][通常論文]
     
    © 2017, Akadémiai Kiadó, Budapest, Hungary. This study attempts to use bibliometry as a tool for exploration of the passage of development of the science and technology through analysis of the scientific publications from a developing country by taking into account its state of higher education and the unique political, economic and geo-bio-environmental conditions. It deals with Nepal considering its scientific output during 1966–2016 reflected as publications indexed in the Web of Science Database. Preliminary examination of the publication record for Nepal reveals a number of the following characteristics: (1) low volume, negligible growth and lack of distinct trend until 1989; (2) a marked growth followed by stagnation linked to political instability during the next 15 years; and (3) recovery and accelerated growth thereafter. Research publications during 2004–2013 increased thrice compared to 1994–2003, with expansion and shifts in disciplinary profile expressed in Essential Science Indicators 22 fields. Detailed bibliometric analysis of the 2004–2013 publications (3011 articles and reviews) from Nepal suggests the citation impact of about the world average, but very high (76%) average international co-authorship. The disciplinary profile is diverse judging from seven most productive fields (clinical medicine, plant and animal science, environment/ecology, geosciences, agricultural sciences, and chemistry) with 4–40% national disciplinary share. Clinical medicine, geosciences and agricultural sciences exhibit relatively high impact. Fields with the smaller share (< 3%), such as molecular biology and genetics, economics and business, psychiatry and psychology, materials science, and biology and biochemistry, exhibit citation impact distinctly higher than the world average. Publications from Nepal show the presence of a vast international collaborative network that is dominated by authors affiliated to institutions in the USA, India, UK, Japan, South Korea and Germany. Based on the analysis of the disciplinary diversity and the national versus global relative disciplinary shares, Nepal’s publication profile is inferred to be a hybrid of the ‘bio-environmental’ and ‘western’ models. Concerning the state of the development of science and technology in Nepal during 2004–2013, the high dependence on international collaboration in the internationally visible publications in most of the bio-environmental, physico-chemical and engineering fields points to basically a ‘building-up stage’. In clinical medicine (with a large share of public health) and geosciences, however, Nepal has demonstrated research strengths evident from the high citation impact in these fields. Moreover, the available data suggest that significant advances were made in higher education sector in both fields during the last 25 years. Despite the notable negative effect of the prolonged domestic armed political conflict on the research activities and acquisition of new data in the field-based sciences, the post-conflict period shows signs of recovery in both domestic and international collaborations leading to again an accelerated growth in scientific publications.
  • Pitambar Gautam Proceedings - 2016 5th IIAI International Congress on Advanced Applied Informatics, IIAI-AAI 2016 523 -528 2016年08月 [査読無し][通常論文]
     
    © 2016 IEEE. This study attempts a comparative disciplinary analysis of a Web of Science (WoS) recorded dataset (ca. 15,000 core journal articles and reviews) of real publications for 5-years period by the research departments, dedicated to science, technology, engineering, mathematics, and medicine (STEMM), of a comprehensive university using different disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, SCOPUS 27 subject areas and OECD Frascati 38 subordinate research fields. It demonstrates that assigning the publications to departments and disciplines followed by correspondence analysis and clustering of the contingency table comprising disciplinary share of publications results in enhanced understanding and visualization of the research output at different levels of disciplinary or research entities. Such exercise improves creation of publication subsets (for different research entities and disciplinary schemes) for further processing, visualization and interpretation with sophisticated bibliometric/scientometric tools including the science mapping techniques.
  • Magnetic susceptibility as a potential tool for geological differentiation of the Lesser Himalayan rocks in central Nepal
    Gautam, P. and Ulak, P. D. and Gyawali, B. and Bhandari, S. Journal of Nepal Geological Society 18 2010年 [査読有り][通常論文]
  • Integration of magnetic properties and heavy metal chemistry to quantify environmental pollution in urban soils, Kathmandu, Nepal
    Gautam, P.; Blaha, U.; Appel, E.;  Himalayan Journal of Sciences 2 (4) 140 -141 2008年 [査読有り][通常論文]
  • Palaeoenvironmental events and cycles at the southern front of the Tibetan Plateau during the Pleistocene: A record from lake sediments
    Appel, E.; Goddu, S.R.; Hu, S.; Yang, X.; Wang, S.; Igarashi, Y.; Gautam, P.;  Himalayan Journal of Sciences 2 (4) 94 -95 2008年 [査読有り][通常論文]
  • Towards magnetic susceptibility mapping of environmental pollution in Kathmandu urban area, Nepal
    Gautam, P. and Appel, E. and Blaha, U. and Neupane, G. EGS-AGU-EUG Joint Assembly 1 2325 2003年 [査読有り][通常論文]
  • Towards a separation of different rotation processes and quantification of rotational underthrusting in the Western Himlayas (N India) deduced from secondary pyrrohotite remanences
    Schill, e and Appel, E. and Zeh, O. and Singh, V. K. and Gautam, P. Journal of Asian Earth Sciences 19 (3A) 55 -56 2001年 [査読有り][通常論文]
     
    Magnitudes of crustal shortening of northern margin of India since collision with Eurasia of about 600 km (Coward et al., 1988; Klootwijk et al., 1991) and 500-1500 km (Besse et al., 1984; Patriat and Achache, 1984; Dewey et al., 1989; Chen et al., 1993; Patzelt et al., 1996) have been concluded in the western and central Himalayas, respectively, from mass balancing and palaeomagnetic results. An indentation of NE India over about 2000 km or more has been visualised by tomographic imaging (Van der Voo et al., 1999). The crustal shortening within the Indian plate is controlled by straight forward shortening in N-S direction and shortening due to rotational underthrusting. The amount of the rotational shortening between the stable Indian plate and the Tethyan Himalayas appears to be overlain by other rotation processes. The most obvious is the oroclinal bending of the whole Himalayas parallel to a small-circle around an Euler pole at the locality Turfan (42.49°N, 91.1°E, radius: 1695 km; Klootwijk and Conaghan, 1985). This combination of rotational underthrusting and oroclinal bending is modulated by tectonic rotations on smaller scales (?100 km and ?10 km). Our study leads to a quantification of rotational shortening on the base of a detailed rotation model. New palaeomagnetic results from metacarbonates of the Tethyan Himalayas in Sarchu, Losar, and Spiti area (N India) show a characteristic remanent magnetisation carried by pyrrhotite (unblocking spectrum: 250-330°C). Negative fold tests (99% level after McElhinny, 1964; McFadden, 1990) indicate remanence acquisition after the main folding of the Himalayas. The formation of pyrrhotite on the expense of magnetite in marly carbonates during thermal events (T> 200°C; Lambert, 1973) suggests remanence acquisition related to exhumation and cooling. Temperatures of about 200-300°C based on illite crystallinity indicate a thermochemical remanence acquisition. 40Ar/ 39Ar ages on illites of 47-42 Ma (Bonhomme and Garzanti, 1991; Wiesmayr and Grasemann, 1999) in NW Zanskar and Spiti indicate an age of remanence acquisition related to the Eohimalayan event. The resulting rotation angles in respect to stable India show an 'anomalous' counterclockwise rotation in NW Zanskar and a trend of decreasing clockwise rotations to the SE (Fig. 1). This variations may be attributed to meso-scale effects and oroclinal bending. For the first time the rotations in respect to stable India were separated into local, meso-scale and regional significant ones. After elimination of local and meso-scale effects, using structural analysis of late orogenic features, modelled rotations due to oroclinal bending were subtracted. Regionally significant rotations of 0-20° clockwise are obtained which can be interpreted to be caused only by rotational underthrusting.
  • Tertiary Block Rotations and Pyrrhotite/Magnetite Geothermometry in the Tethyan Himalaya (Shiar Khola, Central Nepal)
    Schill, E.; Appel, E.; Gautam, P.;  Earth Science Frontiers, China University of Geosciences Bejing 7 58 -59 2000年 [査読有り][通常論文]
  • ON THE NATURE OF REMANENCE IN THE ANDESITE PUMICE WITH SELF-REVERSED MAGNETIZATION FROM THE NEVADO DEL RUIZ, COLOMBIA
    Fujiwara, Y. and Gautam, P. and Yoshida, M. and Katsui, Y. Rock Magnetism and Paleogeophysics 14 7 [査読有り][通常論文]

大学運営

学内役職歴

  • 2017年4月1日 - 2019年3月31日 研究戦略室室員

委員歴

  • 2012年 - 現在   北海道大学・ProSPER.Net(アジア・太平洋環境大学院ネットワーク)    Task Force メンバー
  • 2011年 - 現在   北海道大学国際競争力戦略チーム   アソシエトマネージャー


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