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Mid-Holocene climate change in North china, and the effect on cultural development

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Chinese Science Bulletin 2002年第5期47卷 408-413页

作者： JIN Guiyun & LIU Dongsheng (LIU Tungsheng)institute of Cultural Relics and Archaeology of Shandong Province, Jinan 250012, china institute of geology and {4., Chinese Academy of Sciences, beijing 100029, china institute of Cultural Relics and Archaeology of Shandong Province Jinan China institute of geology and geophysics Chinese Academy of Sciences Beijing China

In this study, to reconstruct the paleoclimatic history, pollen and oxygen isotope were analyzed on the 160 samples of a 2.7 m peat core from Taishizhuang, Huailai County, Hebei Province. Combining our data with other information of climate history and archaeology from this area, we found that there is a close linkage between cultural development and the mid-Holocene (6000-3000 cal. aBP) environment changes. The main results and conclusions are presented as the following: The climate during 5678-54.0 cal. aBP was unstable and in general colder and drier than today. From 54.0 to 4.00 cal. aBP the climate was much warmer and wetter than before. The climate during 4.00-4.00 cal. aBP was persistently cold, with an exceptional cold event occurring at 4.00-4.00 cal. aBP. This cold event was recorded at several other localities in Northern china even the Northern Hemisphere and played an important role in the cultural development. After the cold event, there was a return to warmer conditions between 4.00 and

关键词： North china peat mid-Holocene cold event cultural development.

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern china:Implication for lithospheric evolution

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Science china Earth Sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1, SUI Jianli2, XU Ping2, LI Ni1, SUN Qian1 & WANG Tuanhua1 1. institute of geology, china Seismological Bureau, beijing 100029, china 2. institute of geology and geophysics, Chinese Academy of Sciences, beijing 100029, china institute of geology China Seismological Bureau Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

Minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern china (North china, Northeastern china and Southeastern china coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2 (60%—68%) and alkalis (K_2O+Na_2O = 5%—11%, especially for K_2O) as well asvolatiles such as H_2O and CO_2 (2%—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2O > 3%) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern china. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern china.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern china.

Early-Middle Permian Reef Frameworks and Reef-building Models in the Eastern Kunlun Mountains

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Acta Geologica Sinica(English Edition) 2001年第2期75卷 115-125页

作者： TIAN Shugang institute of geology, Chinese Academy of Geological Sciences, beijing 100037and FAN Jiasong institute of geology and geophysics, Chinese Academy of Sciences, beijing 100029 Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Reef frameworks and building models of the Early-Middle Permian in the eastern Kunlun Mountains have been verified through studies of reef-building communities, palaeoecology and carbonate facies. The eastern Kunlun reefs are built mainly by 6 reef-building communities, which include 11 major categories of frame-building organisms and 6 categories of reef-associated organisms. Eight types of reef-frames have been distinguished and eleven kinds of rocks identified to belong to 6 reef facies. Three sorts of reefs classified by previous researchers, namely mudmounds, knoll reefs and walled reefs, are well developed in the study area. Such reef-facies association and reef distribution show that there are 4.models of reef growth and development, i.e. the tidal-bank knoll-reef model, the plateau-margin wall-reef model, the composite wall-reef model and the deep-water mudmound model. The reefs are mainly constructed by calcareous sponge and calcareous algae, which are similar to all Permian reefs in other area

关键词： reef model Early-Middle Permian eastern Kunlun reefs

Geochemical Characteristics and Tectonic Setting of the Laohushan Basalts, North Qilian Mountains

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 452-457页

作者： QIAN Qing and ZHANG Qi institute of geology and geophysics, CAS, P. O. Box 9825, beijing 100029 CAS Inst Geol & Geophys Beijing 100029 Peoples R China

The Ordovician Laohushan ophiolite, located in the eastern part of the North Qilian Mountains, is mainly composed of meta-peridotites, gabbros and basalts alternating with sediments. The sediments are mainly turbidites, including sandstones, siltstones, cherts etc. Major elements show that the basalts are subalkaline tholeiites and may be analogous to ocean-floor basalts. Except a few N-MORBs, most of the basalts are E-MORBs as indicated by incompatible element ratios such as (La/Ce)N, La/Sm, Ce/Zr, Zr/Y and Zr/Nb. Negative Nb anomaly is common but negative Zr, Hf and Ti anomalies are quite rare. Based on the geochemical characteristics, it is suggested that the Laohushan basalts were formed in a back-arc basin. ENd (t) of the basalts ranges between +3.0 and +8.9 and (87Sr/86Sr), ranges between 0.7030 and 0.7060, indicating a depleted mantle source which was mixed with more or less enriched mantle components. Furthermore, the petrography of the sandstones and geochemistry of the cherts suggest that the sediments were deposited near a continental margin.

关键词： North Qilian Mountains Laohushan basalts sediments geochemistry

Typical basin-fill sequences and basin migration in Yanshan, North china ——Response to Mesozoic tectonic transition

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Science china Earth Sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of geology and geophysics, Chinese Academy of Sciences, beijing 100029,{4. 2.{4. University of Geosciences, beijing 100083,{4.Correspondence should be addressed to Li Zhong (email: lizhongd@***) institute of geology and geophysics Chinese Academy of Sciences Beijing China china University of Geosciences Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North china may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

Synergetic-bifurcated prediction model of slope occurrence and its application

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Science china(Technological Sciences) 2003年第Z1期46卷 69-77页

作者： HUANG Zhiquan & WANG Sijing North china institute of Water Conservancy and Hydroelectric Power, Zhengzhou 4.0008, china institute of {4. & geophysics, Chinese Academy of Sciences, beijing 100029, china N china Inst Water Conservancy & Hydroelect Power Zhengzhou 450008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Landslide prediction is one of the most important aspects of prevention and control for geological hazards and the environmental protection. In order to study the nonlinear methods for landslide prediction, the synergetic-bifurcated model of predicting the timing of slope failure is established by combining Synergetics with Bifurcation Theory based on single-state variable friction law in this paper. The synergetic effects and bifurcated process of the factors in the slope evolution can be characterized in the model. Taking the Xintan Landslide as an example, the prediction of landslide is carried out based on the model suggested.

关键词： friction law, landslide, synergetic-bifurcated model, time prediction.

Magma underplating and Hannuoba present crust-mantle transitional zone composition: Xenolith petrological and geochemical evidence

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Science china Earth Sciences 2005年第8期48卷 1089-1105页

作者： FAN Qicheng1,2, ZHANG Hongfu1, SUI Jianli1, ZHAI Mingguo1, SUN Qian2 & LI Ni2 1. institute of geology and geophysics, Chinese Academy of Sciences, beijing 100029,{4. 2. institute of geology,{4. Seismological Bureau, beijing 100029,{4. institute of geology and geophysics Chinese Academy of Sciences Beijing China institute of geology China Seismological Bureau Beijing China

On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic.

关键词： magma underplating, xenolith petrology, geochemistry, cust-mantle boundary constituent, Hannuoba.

Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

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Progress in Natural Science:Materials International 2007年第3期17卷 305-313页

作者： YAN Zhen, YU Liangjun, LI Jiliang, BIAN Qiantao, WANG Zongqi and YANG Yongcheng ( institute of geology, Chinese Academy of Geological Sciences, beijing 100037, china State Key Laboratory of Lithospheric Evolution, institute of geology and geophysics, Chinese Academy of Sciences, beijing 100029, china Shaanxi Insititute of geology Survey, Xianyang 712000, china) institute of geology Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Shaanxi Insititute of geology Survey Xianyang 712000 China

The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy, and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.

关键词： Middle-Upper Triassic fluvial-lake environments tide environment tempestite Songpan-Ruoergai

Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3, Xu Guanjun1,4. Zhu Cuishan2,3, Xiao Tingrong4. Zhang Min2,3 and Zhang Bin1,4.1. Key Laboratory of Petroleum Geochemistry, china National Petroleum Corporation, beijing 100083, china 2. Geochemistry Department of Yangtze University, Jingzhou 4.4.23, china 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze University, Jingzhou 4.4.23, china 4. Petroleum geology Central Laboratory, Research institute of Petroleum Exploration and Development, Petrochina, beijing 100083, china) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry Department Yangtze University Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Yangtze University Jingzhou 434023 China Petroleum geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil