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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2268-2282页

作者： Rajeev SARASWAT Manumalenki MANASA Thejasino SUOKHRIE Mohammad Syed SAALIM Rajiv NIGAM micropaleontology Laboratory CSIR-National Institute of Oceanography

A total of 97 surface sediment samples were collected from the continental shelf and slope of the western Bay of Bengal to assess the potential application of Asterorotalia trispinosa as a paleomonsoon proxy. The relative abundance of living as well as total （living and dead） A. trispinosa ranges from being absent to a maximum of-31%. The highest abundance ofA. trispinosa is close to the outfall region of the Ganga-Brahmaputra Rivers and decreases away from the river mouths. Contrary to that, A. trispinosa is rare in front of both the Cauvery and Pennar river outfall regions, in the central part of the western Bay of Bengal. The living A. trispinosa abundance is the lowest in between two major river systems, viz. Ganga-Brahmaputra-Mahanadi and Krishna-Godavari. The relative abundance of both the total and living A. trispinosa is strongly positively correlated with ambient seawater temperature, and negatively correlated with %Corg and salinity. Based on the spatial distribution, we conclude that A. trispinosa is stenohaline in nature, rather than euryhaline, and further that the increased relative abundance of A. trispinosa indicates warmer and only marginally hyposaline environment. Even though the ecological preference of A. trispinosa suggests it as a potential paleomonsoon proxy, the restricted distribution implies limited application.

关键词： Asterorotalia trispinosa ecology paleomonsoon riverine influx Bay of Bengal

Does Glacial-Interglacial Transition Affect Sediment Accumulation in Monsoon-Dominated Regions?

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1079-1094页

作者： Dharmendra Pratap SINGH Rajeev SARASWAT Dinesh K.NAIK micropaleontology Laboratory Geological Oceanography DivisionNational Institute of Oceanography

The spatio-temporal changes in sedimentation rate along the continental margin of the monsoon-dominated eastern Arabian Sea during the last 24 kyr have been estimated from a compilation of 58 radiocarbon dated cores, in order to understand the effect of glacial-interglacial variation on sedimentation. The sedimentation rate has been computed for four-time slices, viz. the last glacial maximum, glacial-interglacial transition, early Holocene and late Holocene. We report that the average sedimentation rate in the slope to the abyssal region of the entire eastern Arabian Sea, although higher during the Holocene as compared with that during the last glacial maximum and glacial-interglacial transition, does not significantly vary during all four-time intervals. The sedimentation rate during any particular time interval, however, varies from core to core, thus indicating zonal changes. We report four zones of relatively high sedimentation rate, viz. the northeastern Arabian Sea, the region off the Gulf of Khambhat, the region off Goa and Mangalore, and off the southern tip of India. We suggest that a complex interaction of land-ocean-atmospheric processes controlled sedimentation rate in the eastern Arabian Sea during the last 24 kyr in such a way that the average sedimentation rate does not vary significantly, even during highly contrasting climatic conditions.

关键词： Sedimentation rate monsoon glacial Holocene Arabian Sea

The Global Standard Stratotype-section and Point （GSSP） for the base of the Eocene Series in the Dababiya section （Egypt）

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Episodes 2007年第4期30卷 271-286页

作者： Marie-Pierre Aubry Khaled Ouda Christian Dupuis William A., Berggren John A. Van Couvering 无 Department of Earth and Planetary Sciences Rutgers University 610 Taylor Road Piscataway New Jersey 08554 USA8 Department of Geology University of Assiut Assiut Egypt Géologie Fondamentale et Appliquée Mons PolytechnicsRue de Houdain 9 B-7000 Mons Belgium the micropaleontology project 256 Fifth Avenue New York NY 10001 USA the Members of the Working Group on the Paleocene/Eocene Boundary

The GSSP for the base of the Eocene Series is located at 1.58 m above the base of Section DBH in the Dababiya Quarry, on the east bank of the Nile River, about 35 km south of Luxor, Egypt. It is the base of Bed 1 of the Dababyia Quarry Beds of the El Mahmiya Member of the Esna Formation, interpreted as having recorded the basal inflection of the carbon isotope excursion （CIE）, a prominent （3 to 5%） geochemical signature which is recorded in marine （deep and shallow） and terrestrial settings around the world. The Paleocene/Eocene boundary is thus truly a globally correlatable chronostratigraphic level.

关键词：层型断面始新世第三纪下层埃及

First Late Triassic Record of a Paleoentomofauna from South America(Malargüe Basin,Mendoza Province,Argentina)

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 915-924页

作者： Carsten BRAUCKMANN Oscar F.GALLEGO Norbert HAUSCHKE Rafael G.MARTINS-NETO Elke GROENING Jan-M.ILGER María B.LARA Geology and Palaeontology Clausthal University of TechnologyLeibnizstrasse 10D-38678 Clausthal-ZellerfeldGermany micropaleontology(Faculty of Natural Sciences-National Northeast University) 3400 Corrientes-Argentina Palaeontology Area(Center of Applied Ecology of the Litoral-National Research Council) 3400 Corrientes-Argentina Geosciences Martin Luther University Halle-WittenbergVon-Seckendorff-Platz 3D-06120 Halle(Saale)Germany Federal University from Ceara Cariri/FUNCAPPresident Brazilian Paleoarthropodological SocietyBrazil

Late Middle Triassic to early Late Triassic insects from Argentina have been previously described from the Bermejo and Cuyana Basins where they have been recovered from the Ischichuca-Los Rastros and Potrerillos-Cacheuta Formations, respectively. The insect fauna discussed herein was collected during field studies in 1986/1987 from the Llantenes section （Norian to Rhaetian？ Late Triassic）, which is situated in the Malargiie Basin in southern Mendoza province. The insect remains were found in the upper part of the Llantenes section （Llantenes Formation）, which is built up of two coarsening-upwards cycles reflecting a deltaic progradation of a fluvial into a lacustrine environment （lower part）, succeeded by repeated progradatious into a floodplaindominated environment （upper part; with finds of insects, conchostracans, fish remains, plant fragments, and drifted logs）. The new finds represent the youngest Triassic insect records described from Argentina and even from South America in its entirety. There is only one contemporaneous fossil assemblage in Gondwana： in the Ciarence/Moreton Basin （Aberdare Conglomerate; Late Norian） in Australia. The new Triassic insects include an impression of an isolated Mecopterida-like wing （Mendozachorista volkheimeri gen. et sp. nov.; Mendozachoristidae fam. nov.）, coleopteran elytra of the Permosynidae （Ademosyne rosenfeldi sp. nov. and Ademosyne Uantenesensis sp. nov.） and other isolated body fragments. This new Late Triassic entomofauna from Argentina is of considerable importance in the reconstruction of the biotic recovery of continental environments in Gondwana after the catastrophic mass extinction at the P/T boundary.

关键词： Mecopterida Coleoptera Late Triassic Liantenes Formation Malargiie Basin Argentina

第四纪:它的地位、时限、定义和存在的必要性

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第四纪研究 2005年第6期25卷 666-669页

作者： M.-P.Aubry W.A.Berggren J.van Couvering B.McGowran B.Pillans F.Hilgen 韩家懋 Department of Geological Sciences Rutgers University610 Taylor RoadPiscatawayNJ08854-8066USA Department of Geological Sciences Rutgers University610 Taylor RoadPiscatawayNJ08854-8066USADepartment of Geology and GeophysicsWoods Hole Oceanographic InstitutionWoods HoleMa02543USA the micropaleontology project 256 Fifth AvenueNew York CityNYUSA School of Earth & Environmental Sciences The University of AdelaideDP313Adelaide SA5005 Australia Research School of Earth Sciences The Australian National UniversityCanberra ACT0200Australia Institute of Paleoenvironments and Paleoclimate UtrechtBudapestlaan43584 CD UtrechtThe Netherlands

作为年代地层单位的术语,'第四纪'长期以来一直存在着争议,从最近发表的一些论文[1,2]以及论文所附的文献把这一争议推向极点.尽管过去对这一术语存在不确定性,但不能否认在对地球历史的研究中,大部分人是认同这一术语的.目前,争议已经... 详细信息

作为年代地层单位的术语,'第四纪'长期以来一直存在着争议,从最近发表的一些论文[1,2]以及论文所附的文献把这一争议推向极点.尽管过去对这一术语存在不确定性,但不能否认在对地球历史的研究中,大部分人是认同这一术语的.目前,争议已经不再集中在术语'第四纪'是否应该在地质年代表中占有一个位置,而争论的焦点在于给'第四纪'以合适的时间范围,以及相对于其他的地质年代单位,给予第四纪一个确切的定义.现已有好几个方案被提出来[1,2],Gibbard等[2]倡导在最后的决定作出之前,对这些方案进行深入讨论.在这一篇短文中,我们提出了一个前人尚未提出过的方案,我们认为这对问题的最后解决是有利的.首先,我们回顾一下将第四纪放在地质年代表和作为一个地质年代单位的两个地质时期,即更新世和新近纪的直接影响.

关键词：第四纪时限定义刘东生

Evolution Characteristics and Stratigraphic Division of Quaternary Sedimentary in the South Wing of Yangtze River Delta, East China

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Evolution Characteristics and Stratigraphic Division of Quat...