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Paleomagnetic study on orogenic belt:An example from Early Cretaceous volcanic rocks,Inner Mongolia,china

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Science china Earth sciences 2004年第12期47卷 1127-1133页

作者： REN Shoumai 1,2 ,ZHU Rixiang 1 ,HUANG Baochun 1 ,ZHANG Fuqin 1 & wang Hongqiang 1 1.institute of Geology and geophysics,Chinese academy of {4.,beijing 100029,china 2.Strategic Research Center for Oil and Natural Gas,The Ministry of Land and Resources of china,beijing 100034.china Strategic Research Center for Oil and Natural Gas The Ministry of Land and Resources of China Beijing China Chinese academy of sciences Institute of Geology and Geophysics Beijing China

We report paleomagnetic results for Early Cretaceous lava flows collected from the Suhongtu area of Inner Mongolia, the middle part of the Tianshan-Mongolia Fold Belt (TMFB). Rock-magnetic experiments for different lava flows indicate that the main magnetic mineral is pseudo-single-domain (PSD) magnetite. The characteristic high-temperature remanence com- ponent is isolated by thermal demagnetization temperature steps between 300°C and 585"C, which yields a mean direction of D = 23.6°, I=56.0° with α 95 = 2.3°. We interpret this high-temperature remanence component as primary magnetization based mainly upon the petrographic analysis, which shows that the shape of magnetite crystal is relatively rounded square or polygon without internal reflection and deuterogenous phenomenon. The correspond- ing pole of the high-temperature remanence component is at 71.1°N, 200.5°E with A 95 = 2.7°. This Early Cretaceous pole is in good agreement with those for Siberia, North china, and Inner Mongolia, suggesting that these continental blocks had already sutured together in the Early Cretaceous, which would further provide constraints on better understanding of the formation and evolution of the TMFB.

关键词： orogenic belt, paleomagnetism, Suhongtu of Inner Mongolia, Eurasia.

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, wang Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. institute of Geology and geophysics, Chinese academy of {4., beijing 100029, china 2. institute of geophysics, china Seismological Bureau, beijing 100085, china 3. institute of Deposition Resource, Chinese academy of Geo{4., beijing 100037, china 4. School of Exploration and Information, china University of Geo{4., beijing 100083, china institute of Geology and geophysics Chinese Academy of Sciences Beijing China institute of geophysics China Seismological Bureau Beijing China institute of Deposition Resource Chinese Academy of Geosciences Beijing China School of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, wang Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese academy of sciences, Guangzhou 51064., {4. 2. Graduate University of Chinese academy of sciences, beijing 100039, {4. 3. SHRIMP isotope Laboratory, Chinese academy of Geological sciences, beijing 100037, {4. 4. institute of Geology and {14., Chinese academy of sciences, beijing 100029, {4. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4.± 3.0 Ma and 230.4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±4. Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Crustal structure of Gondwana-and yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china Earth sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, wang Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, SUN Shanxue1 & wang Xinzheng1 1. institute of Geology and geophysics, Chinese {4. of sciences, beijing 100029, china 2. institute of geophysics, Chinese Seismological Bureau, beijing 100081, china 3. institute of Deposition Resource, Chinese {4. of Geological sciences, beijing 100037, china institute of Geology and geophysics Chinese Academy of Sciences Beijing China institute of geophysics Chinese Seismological Bureau Beijing China institute of Deposition Resource Chinese Academy of Geological Sciences Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern yangtze blocks (yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 4. km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and yangtze blocks.

关键词： Gondwana blocks,yangtze blocks,wide-angle profile,crustal structure,tectonic setting

Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2 gas field

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Science china Earth sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, wang Hongjun1, SHAN Jiazeng2, wang Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, {4. 100083, china 2. institute of Geology and geophysics, Chinese academy of sciences, {4. 100029, china Research institute of Petroleum Exploration and Development Petrochina Beijing China institute of Geology and geophysics Chinese Academy of Sciences Beijing China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2 gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

Functional characterization of Bmcap in uric acid metabolism in the silkworm

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Insect Science 2024年第1期31卷 147-156页

作者： Linmeng tang Dehong yang Zhiwei Liu Yaohui wang Xu yang Yujia Liu Dongbin Chen Zheng tang Yongping Huang Key Laboratory of Insect Developmental and Evolutionary Biology Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina Central Research institute Shanghai Pharmaceuticals Holding Co.Ltd.ShanghaiChina Departments of Neonatology International Peace Maternity and Child Health Hospital of China Welfare InstitutionSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

After a millennium of domestication,numerous silkworm mutants have emerged that exhibit transparent epidermis,which is caused by abnormally low levels of uric *** identified the Bombyx mori gene Bmcap(BMSK0003832)as the homolog of cappuccino,a subunit of the biogenesis of lysosome-related organelles complex-1(BLOC-1)that has been extensively characterized in human,mouse,and insect species,by analyzing the amino acid sequences of putative purine metabolism *** the clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 system,we disrupted Bmcap,resulting in decreased uric acid levels in the silkworm epidermis and a translucent skin *** the Bmcap mutant,the purine metabolism,nitrogen metabolism,pyrimidine metabolism,and membrane system were altered compared to the wild *** of lysosome-related organelle complex genes play a role in the pigmentation and biogenesis of lysosome-related organelles(LROs)in platelets,melanocytes,and *** exhibit unique morphologies and functions in various tissues and *** of the Bmcap mutant will enhance our understanding of the uric acid metabolic pathway in silkworms,and this mutant offers a valuable silkworm model for LRO studies.

关键词： BLOC-1 subunit Bombyx mori cappuccino translucent mutation uric acid

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2, wang Pinxian1, CHENG Xinrong1, wang Rujian1 & SUN Xiangjun1,3 1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 2. institute of Geology and {4., Chinese academy of sciences, beijing 100029, china 3. institute of Botany, Chinese academy of sciences, beijing 100093, china Tongji University Chinese academy of sciences

The deep sea records from the ODP Sites 114. and 114. in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 4. ka and 23 ka cycles. Although G. ruber δ 13C of Site 114. is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

Gravity anomaly during the Mohe total solar eclipse

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Chinese Science Bulletin 2001年第21期46卷 1833-1836页

作者： wang qianshen yang xinshe {4. keyun institute of geophysics Chinese Academy of SciencesBeijing 100101China Department of Applied Mathematics University of LeedsLeeds LS2 9JTUK

By using a high-precision LaCoste-Romberg (D-122#) gravimeter, continuous and precise measurements were carried out during the March 9,1997 total solar eclipse in the Mohe region in Northeast china. The gravity variations were digitally recorded during the total solar eclipse so as to investigate the possible anomaly of the sun and the moon’s gravitational fields on the earth. After the careful processing and analysis of the observed data, no significant anomaly during the very solar eclipse has been found. However, there are two ’gravity anomaly valleys’ with near symmetrical decrease of about 6-7 μGal at the first contact and the last contact. This is the anomaly phenomenon observed and reported for the first time in the literature. This note presents some analyses and discussions.

关键词： Mohe total solar eclipse gravity anomaly.

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14.million years ago

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Science china Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, wang Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4. TAN Hongbing2 & wang Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, Chinese academy of {4., Xi’an 710075 china 2. Qinghai institute of Salt Lakes, Chinese academy of {4.. Xining 810008, china 3. institute of Geology and geophysics, Chinese academy of {4., {14. 100029, china 4. Department of Geography, Qinghai Normal University, Xining 810008, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of Geology and geophysics Chinese Academy of Sciences Beijing China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China Department of Geography Qinghai Normal University Xining China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14.million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4.00 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2, T1 were formed at 14. 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14.million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14. 11.3, 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 4.2 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.