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Science China Earth Sciences 2010年第5期53卷 633-641页

作者： EDWARDS R. Lawrence department of geology and geophysics University of Minnesota

Based on 33 U/Th dates and 1020 oxygen isotopic data from stalagmite Y1 from Yamen Cave, Guizhou Province, China, a record of the Asian Summer Monsoon (ASM) was established. The record covers the last deglaciation and the early Holocene (from 16.2 to 7.3 ka BP) with an average oxygen isotope resolution of 9 years. The main millennial-scale deglacial events first identified in Greenland (Greenland Interstadial Events: GIS 1e through GIS 1a) and later in China are clearly present in the Y1 record. By analogy to earlier work, we refer to these as Chinese Interstadials (CIS): CIS A.1e to CIS A.1a. The onset of these events in Y1 δ18O records are nominally dated at: 14750±50, 14100±60, 13870±80, 13370±80, and 12990±80 a BP. The end of CIS A.1a or the beginning of the Younger Dryas (YD) event is nominally at 12850±50 a BP and the end of the YD dates to 11500±40 a BP. The δ18O values shift by close to 3‰ during the transition into the Bφlling-Allerφd (BA, the onset of CIS A.1e) and at the end of the YD. Comparisons of Y1 to previously published early Holocene records show no significant phase differences. Thus, the East Asia Monsoon and the Indian Monsoon do not appear to have been out of phase during this interval. The Y1 record confirms earlier work that suggested that solar insolation and North Atlantic climate both affect the Asian Monsoon.

关键词： stalagmite Asian Monsoon the last deglaciation Holocene U-series dating Yamen Cave

Some Issues on the Strength of the Lithosphere

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Journal of Earth Science 2011年第2期22卷 131-136页

作者： Shun-ichiro Karato department of geology and geophysics Yale University

The strength of the oceanic and continental lithosphere has important controls on some of the major geological processes on earth including the operation of plate tectonics and the long-term stability of the continental roots. However, explaining these major geological features from the experi- mental and theoretical studies on the strength of rocks is challenging and some of the existing models for the strength of the lithosphere do not explain these main geological observations. A brief review is provided to summarize recent progress in these areas with the emphasis on experimental studies.

关键词： lithosphere plate tectonics continent.

An exceptionally strengthened East Asian summer monsoon event between 19.9 and 17.1 ka BP recorded in a Hulu stalagmite

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Science China Earth Sciences 2009年第3期52卷 360-368页

作者： L. R. EDWARDS department of geology and geophysics University of Minnesota Minneapolis

A stalagmite-based isotope record (No. H82) from Nanjing Hulu Cave, spanning from 16.5 to 10.3 ka BP, provided strong evidence for a coherence relation between the East Asian summer monsoon (EASM) and the North Atlant... 详细信息

关键词： Nanjing Hulu Cave stalagmite East Asian summer monsoon event

Review of the bennettitalean genus Weltrichia

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Journal of Palaeogeography 2019年第2期8卷 109-129页

作者： Mihai Emilian Popa Faculty of geology and geophysics Department of Geology and Doctoral School of GeologyLaboratory of PalaeontologyUniversity of Bucharest

The bennettitalean male reproductive structure Weltrichia Braun 1849 *** 1969(Family Williamsoniaceae) is discussed from several points of view,including anatomy and morphology,species diversity and validity,phytogeographical and stratigraphical distribution,and reproduction strategy.A very rare fossil,genus Weltrichia includes 25 valid species distributed in both hemispheres during Triassic and Jurassic *** contribution critically reviews the systematics of the entire genus,together with its stratigraphical and palaeophytogeographical significance.

关键词： Bennettitales Weltrichia Male reproductive structure Triassic Jurassic

Slope stability analysis of Balia Nala landslide, Kumaun Lesser Himalaya, Nainital, Uttarakhand, India

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 150-158页

作者： Mohit Kumar Shruti Rana Pitamber Dutt Pant Ramesh Chandra Patel department of geology Kumaun University department of geophysics Kurukshetra University

Balia Nala is the outlet of the Nainital lake, flowing towards southeast direction. Presence of Nainital habitation at its right bank has high socio-economic importance. This study presents the stability analysis of a ravine/valley along Balia Nala. Variegated slates(lower Krol and upper Blaini formations) are the main rock types, wherever the outcrop does exist and rest of the area is covered by slope wash and river borne materials. Three sets of joints are presented in the area, but 4 sets of joints also exist at some locations. Nainital lake fault intersected by Manora fault from southwest direction passes through eastern side of the study area, and some small faults, which are sub-branches of Nainital lake fault, are observed(with 10 m offset) and promote the landslide in the area. This study shows that different kinds of discontinuities(joints, faults and shear zones) and rapid down cutting by the stream due to neotectonic activity affect the stability of the slope. The fragile lithology and deep V-shaped valley further accelerate the mass movement in the study area. In addition, rock mass rating(RMR), factor of safety(FOS) and graphical analysis of the joints indicate the study area as landslide-prone zone. This study will be helpful in not only reducing the risk on life of people, but also in assisting the ongoing civil work in the study area.

关键词： Rock mass rating(RMR) Factor of safety(FOS) Balia Nala landslide Slope stability analysis

Complicated responses of stalagmite δ ^(13)C to climate change during the last glaciation from Hulu Cave, Nanjing,China

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Science China Earth Sciences 2005年第12期48卷 2174-2181页

作者： R. L. Edwards department of geology and geophysics University of Minnesota MN 55455 USA

We present a record on carbon stable isotopic composition (δ 13C), covering 75 through 10 thousands years ago (ka B.P.), from Hulu Cave, Nanjing. The overlapping δ 13C pro-files are very similar in pattern and range, indicating that they mainly record climatic signal. Dur-ing the last glacial-interglacial transition, the >6‰ change of δ 13C values implies different con-tributions of C3 vs. C4 type plants in soils. On millennial scale, however, the increased calcite δ 13C during the warm Dansgaard-Oeschger (DO) events suggests a decrease of dissolved bio-genic CO2 when water flux rate through soil is large. This correlation between heavier δ 13C and higher precipitation is consistent with our previous report on the samples’ stable oxygen isotope records (Wang et al., 2001). Comparison of coeval δ 13C and δ 18O of stalagmites indicates that kinetic fractionation of carbon isotope is closely related to growth rate of stalagmites. This study also shows that local vegetation changes may lag behind precipitation changes by ~700 years during the deglaciation.

关键词： Hulu Cave stalagmite δ 13C last glacial period.

On ultrahigh temperature crustal metamorphism:Phase equilibria,trace element thermometry,bulk composition,heat sources,timescales and tectonic settings

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Geoscience Frontiers 2015年第3期6卷 311-356页

作者： David E.Kelsey Martin Hand department of geology and geophysics School of Physical SciencesThe University of Adelaide

Ultrahigh temperature （UHT） metamorphism is the most thermally extreme form of regional crustal metamorphism, with temperatures exceeding 900 ℃. UHT crustal metamorphism is recognised in more than 50 localities globally in the metamorphic rock record and is accepted as ＇normal＇ in the spectrum of regional crustal processes. UHT metamorphism is Wpically identified on the basis of diagnostic mineral assemblages such as sapphirine ＋ quartz, orthopyroxene ＋ sillimanite ＋ quartz and osumilite in Mg-Al- rich rock compositions, now usually coupled with pseudosection-based thermobarometry using internally-consistent thermodynamic data sets and/or Al-in-Orthopyroxene and ternary feldspar thermobarometry. Significant progress in the understanding of regional UHT metamorphism in recent years includes：（1） development of a ferric iron activity-composition thermodynamic model for sapphirine, allowing phase diagram calculations for oxidised rock compositions; （2） quantification of UHT conditions via trace element thermometry, with Zr-in-rutile more commonly recording higher temperatures than Ti-in-zircon. Rutile is likely to be stable at peak UHT conditions whereas zircon may only grow as UHT rocks are cooling. In addition, the extent to which Zr diffuses out of rutile is controlled by chemical communication with zircon; （3） more fully recognising and utilising temperature-dependent thermal properties of the crust, and the possible range of heat sources causing metamorphism in geodynamic modelling studies; （4） recognising that crust partially melted either in a previous event or earlier in a long-duration event has greater capacity than fertile, unmelted crust to achieve UHT conditions due to the heat energy consumed by partial melting reactions; （5） more strongly linking U-Pb geochronological data from zircon and monazite to P-T points or path segments through using Y ＋ REE partitioning between accessory and major phases, as well as phase diagrams incorporating Zr and REE; and （

关键词： Sapphirine + quartz P-T pseudosections Zr-in-rutile Ti-in-zircon U-Pb geochronology Subduction

Bryozoan Nodules as a Frame-Builder of BryozoanMicroreef, Middle Miocene Sediments, Egypt

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Journal of Earth Science 2015年第2期26卷 251-258页

作者： Abdelbaset S.El-Sorogy geology and geophysics department College of Science King Saud University geology department Faculty of Science Zagazig University

Bryozoan nodules, coralline algae, scleractinian corals and oysters form an important organic buildup, 1.2-4.5 m thick in the Langhian-Serravaliann sediments of Egypt. Based on type, shape and size of the substrate, bryozoan nodules take tree-like and globular morphologies. Tree-like speci- mens reach 10 cm in maximum height and 3 cm in diameter, while Globular ones attain 9 cm in maxi- mum diameter. Most tree-like nodules are perforated with wide or narrow pores, few are non-perforated. Globulars and few tree-like forms are with mamelon-like structures. Perforations on the outer surfaces may indicate a symbiotic relationship between bryozoans and a live plant substrate. Nod- ules from Homiera and Gharra areas of the Cairo-Suez District with wider perforations may indicate growth in slightly lighter or turbid areas of the continental shelf than those of North Western Desert of narrower perforations. Non-perforated nodules may assume an incrustation on ephemeral substrate .

关键词： Miocene bryozoa frame builder microreef paleoecology Egypt.

Paleovalley in the Yannan-Sancang area of Jiangsu Province and its geological significance

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Chinese Science Bulletin 1997年第11期42卷 924-927页

作者： Li, CX Wan, MH Chen, CQ department of Marine geology and geophysics Tongji University Shanghai China

IN the southern Yellow Sea there exists a large radial sand ridge system,which covers about20 000 km^*** ridges and troughs occur alternately within the system,and single sandridges are tens of kilometers,even more than one hundred kilometers long and ten to fifteenkilometers *** to the distribution pattern of the radial sand ridge system being like

关键词： digital ground penetrating radar paleovalley radial sand ridge.

Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process

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Science China Earth Sciences 2004年第2期47卷 138-150页

作者： ZHANG Jinjiang, Jl Jianqing, ZHONG Dalai, DING Lin & HE Shundong1. department of geology, Peking University, Beijing 100871, China 2. Institute of geology and geophysics, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Zhang Jinjiang (email: zhjj@***) department of geology Peking University Beijing China Institute of geology and geophysics Chinese Academy of Sciences Beijing China

The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contractional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, ~23 Ma and ~13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma. Keywords Namjagbarwa - eastern Himalayan syntaxis (EHS) - structural pattern - formation process - structural chronology

关键词： Namjagbarwa, eastern Himalayan syntaxis (EHS), structural pattern, formation process, structural chronology.