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51.
ZHANG DaJiang WANG PeiRong MAO ZhiChao & XU GuanJun Research Institute of Petroleum Exploration & Development PetroChina Beijing China Key Laboratory of Petroleum Geochemistry CNPC Geochemistry Department Yangtze University Jingzhou 《中国科学:地球科学(英文版)》2010,(4)
Twenty-five monoterpanes from six types of essential oils and hydrogenated turpentine oil have been identified and their stable carbon isotope composition determined.Monoterpanes in essential oils sourced from terrestrial higher plants display a δ13C value in the range of-34‰-26‰,and mostly between-29‰ and-27‰.The δ13C value of any single monoterpane is very consistent in different essential oils.Acyclic monoterpanes show closer isotope composition between-28.6‰ and-26.2‰,with an average value of-27.7‰.In contrast,the isotope composition of cyclic monoterpanes is more scattered with an average value of-28.6‰.Isotopic fractionation with 13C enrichment has been observed during both artificial and geological hydrogenation of monoterpenoids to monoterpanes,and this is more obvious for the acyclic monoterpenoids.In addition to higher plants,acyclic monoterpane 2,6-dimethylheptane in crude oil can also be originated from other organic inputs. 相似文献
52.
Ridge subduction and porphyry copper-gold mineralization:An overview 总被引:35,自引:0,他引:35
SUN WeiDong LING MingXing YANG XiaoYong FAN WeiMing DING Xing & LIANG HuaYing CAS Key Laboratory of Isotope Geochronology Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Research Center for Mineral Resources School of Earth Space Sciences University of Science Technology of China Hefei Graduate University of Chinese Academy of Sciences Beijing Key Laboratory for Metallogenic Dynamics ... 《中国科学:地球科学(英文版)》2010,(4)
Many large porphyry Cu-Au deposits are connected to adakitic rocks known to be closely associated with ridge subduction. For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are much less there, both in terms of tonnage and the number of deposits. Given that Cu and Au are... 相似文献
53.
ZHANG WeiGuo JIANG JingShan LIU HeGuang ZHANG XiaoHui ZHANG DeHai LI DiHui & XU Chu ong Centre for Space Science Applications Research Chinese Academy of Sciences Beijing China 《中国科学:地球科学(英文版)》2010,(3)
Investigation on Lunar polar area is almost every lunar mission’s primary objective in recent years. The rationale behind it is that illumination and ice resources in this area can be potentially very helpful for constructing lunar human base. In this paper, we analyze microwave radiometric characteristics of the Moon by using the newly acquired Chang’E-1 Lunar Microwave Sounder (CELMS) data. Microwave brightness temperature at Lunar South Pole (LSP) is distributed regularly with a style of "ring-in-ring", decreasing from equator to pole. Regolith temperature gradient is bigger at lunar equator than at polar area. Brightness temperature diurnal difference decreases with observation frequency. Microwave brightness temperature distribution maps at LSP and Lunar North Pole (LNP) have been made based on the analysis. It is found that microwave brightness temperature becomes to synchronize with elevation beyond -85° latitude. This phenomenon is related to lightening condition and indicates temperature distribution at LSP. The brightness temperature anomaly cold points are potentially cold trap areas for water or ice while hot points imply plenty of illumination resources there. 相似文献
54.
GUO HuaDong ZHANG Bing LEI LiPing ZHANG Li & CHEN Yu Center for Earth Observation Digital Earth Chinese Academy of Sciences Beijing China 《中国科学:地球科学(英文版)》2010,(6)
At 7:49 a.m. on April 14th, 2010, an earthquake of 7.1 on the Richter scale occurred in Yushu County, Yushu Tibetan Autonomous Prefecture in Qinghai Province. There was great loss of property and life. 相似文献
55.
DENG Hao ZHANG LiQiang MAO XianCheng MA JingTao KANG ZhiZhong PENG JunHuan RUI XiaoPing & LIU Liu State Key Laboratory of Remote Sensing Science Beijing Normal University Beijing China School of Geoscience Environmental Engineering Central South University Changsha PTV America Inc. Broadway Plaza Ste Tacoma WA USA 《中国科学:地球科学(英文版)》2010,(1)
In the application of 3D Geoscience Modeling,we often need to generate the volumetric representations of geological bodies from their surface representations.Linear octree,as an efficient and easily operated volumetric model,is widely used in 3D Geoscience Modeling.This paper proposes an algorithm for fast and dynamic generation of linear octrees of geological bodies from their surface models under hardware acceleration.The Z-buffers are used to determine the attributes of octants and voxels in a fast way,a... 相似文献
56.
SHUAI YanHua ZHANG ShuiChang SU AiGuo WANG HuiTong CAI BaoYuan & WANG Hui Research Institute of Petroleum & Development Beijing China 《中国科学:地球科学(英文版)》2010,(1)
Sanhu depression of Qaidam Basin is the largest biogenic gas production region in China.Headspace samples were collected from two wells in this region,and hydrogen and propylene compounds were detected in these samples with a certain concentration.The stable hydrogen isotope ratio of H 2 is relatively light (-700‰--820‰).The stable carbon isotope ratio of propylene ranges from -27‰ to -40‰,which coincides with the rule of change of the stable carbon isotope of kerogen at the corresponding horizon.The charac... 相似文献
57.
Conductivity structure and rheological property of lithosphere in Southern Tibet inferred from super-broadband magnetotelluric sounding 总被引:2,自引:0,他引:2
To understand deep lithosphere structure beneath the Qinghai-Tibet Plateau more comprehensively and objectively and to explore important scientific issues,such as characteristics of plateau lithospheric deformation,state of strain,thermal structure,plate (or terrane) movement,and crust-mantle rheology,it is necessary to research the variation of crust-mantle electrical structure in the east-west direction in every geological unit.For this purpose,six super-broadband magnetotelluric (MT) sounding profiles ha... 相似文献
58.
Climate variability recorded by n-alkanes of paleolake sediment in Qaidam Basin on the northeast Tibetan Plateau in late MIS3 总被引:1,自引:0,他引:1
PU Yang ZHANG HuCai LEI GuoLiang CHANG FengQin YANG MingSheng ZHANG WenXiang LEI YanBin YANG LunQing & PANG YouZhi State Key Laboratory of Lake Science Environment Nanjing Institute of Geography Limnology Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of Sciences Beijing Key Laboratory of Boyang Lake MOE School of Environmental Chemical Engineering Nanchang University Nanchang 《中国科学:地球科学(英文版)》2010,(6)
Here we combine n-alkanes preserved in a shell bar section from Qarhan paleolake, Qaidam Basin with the other sedimentary proxies to elucidate the lake evolution process during the period 39.7 to 17.5 14C ka BP (calibrated age ranges from 43.5 to 22.4 cal. ka BP). In different stages, the n-alkane homologues exhibited different distribution modes indicative of variations in the surrounding vegetation and the hydrologic condition of the lake. The n-alkanes proxies (CPIh, ACLh, Paq) have the same trends as th... 相似文献
59.
JI YouLiang ZHOU Yong KUANG Jun WAN Lu ZHANG Rui & LU ChunHong State Key Laboratory of Petroleum Resource Prospecting China University of Petroleum Beijing China Xinjiang Oil Field Urumqi 《中国科学:地球科学(英文版)》2010,(6)
The Chepaizi-Mosuowan paleo-uplift is a large-scale uplift stretching across the Junggar Basin formed during the Yanshanian. It has experienced four evolutionary stages: the initial forming stage (J1), the intense development stage (J2+3), the waning and burial stage (K-E), and the tilting and extinction stage (N-Q). The most intense period of activities is the Middle Jurassic. Dur-ing the Early Jurassic, the Chepaizi-Mosuowan paleo-structure was a low amplitude uplift. Because of the subsequent strong upli... 相似文献
60.
Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern China in warm seasons 总被引:1,自引:0,他引:1
SHI XiaoHui XU XiangDe XIE LiAn State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China 《中国科学D辑(英文版)》2008,(5)
Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 20 a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South China region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern China during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 20 a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern China during a warm season. 相似文献