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181.
A remote sensing model for monitoring soil evaporation based on differential thermal inertia and its validation 总被引:2,自引:0,他引:2
To develop geosciences quantification and multi-dimensional researches will be an inevitable trend in the 21st century. The interaction between the land surface and the atmosphere not only serves as an important component in geosciences quantification, bu… 相似文献
182.
Kinetic study of the hydrocarbon generation from Upper Paleozoic coals in Ordos Basin 总被引:6,自引:0,他引:6
When organic matter during geological processes is affected by a variety of factors such as paleotemperature, and time, complicated chemical reactions will occur, finally resulting in the generation of petroleum and natural gas. These reactions leading to… 相似文献
183.
Evolution mechanism of the western Pacific subtropical high 总被引:4,自引:0,他引:4
Ever since Charney et al.[1] studied the multiple equilibrium states in atmosphere with highly truncated spectral method in 1979, many Chinese researchers, such as Li Maicun et al. (1983)[2], Liu Chongjian et al. (1983)[3], Miu Jinhai et al. (1985)[4] and… 相似文献
184.
Natural gas generation model and its response in accumulated fluids in the Yinggehai basin 总被引:2,自引:0,他引:2
The generation of natural gases is much more complicated in comparison with liquid petro-leum in that natural gases could be generated from both humic and sapropelic organic matter at different stages and that natural gases could be organic and inorganic … 相似文献
185.
From the latest Precambrian to the Early Cambrian was the most important phase throughout the evolutionary history of life on the earth. The diversification of latest Precambrian multicellular organisms was obvious and some of them began to form primary s… 相似文献
186.
Magnetic properties of tidal flat sediments of the Yangtze Estuary and its relationship with particle size 总被引:6,自引:0,他引:6
Since the 1970s, environmental magnetism has found extensive applications in diverse research areas of geoscience[1]. In China, a lot of environmental magnetic studies have been carried out on loess, lake and marine sediments for the purpose of paleoclima… 相似文献
187.
The processes and rates of the weathering denudation of the bare crystalline rock are important problems in the field of geosciences[1—6]. Essentially, the weathering denudation process is the process of rock destruction and transportation. In different … 相似文献
188.
A dating of two biotite samples taken from the meso- and low-temperature mylonites within the Shangyi-Chicheng fault belt
on the north of the North China Craton yields 40Ar/39Ar isotopic ages of (399 ± 1) Ma and (263 ± 2) Ma, respectively. These data reflect an Early Devonian deformation and a Late
Carboniferous retrograde metamorphism event along the fault, suggesting that the tectonic activities of the North China Craton
in Paleozoic should be reconsidered. 相似文献
189.
Yuanbao?WuEmail author Daogong?Chen Qunke?Xia Xianglin?Tu Hao?Cheng Xiaozhi?Yang 《中国科学D辑(英文版)》2003,46(11):1161-1170
It is revealed by CL images that there are multi-stage growth internal structures of zircons in the Huangtuling granulite,
including the inherited zircons, protolith zircons, sector and planar zone zircons and retrograde zircons. In-situ trace element compositions and Pb-Pb ages have been analyzed by LAM-ICP-MS. The sector and the planar zone domains show typical
trace element characteristics of granulite zircon (low Th, U, Th/U, total REEs, clear negative Eu anomalies, relatively depleted
HREE and small differential degree between MREE and HREE, etc.), indicating that they formed during granulite-facies metamorphism.
The protolith zircons have trace element characteristics of crustal zircon (high Th, U, Th/U, total REEs and enriched HREEs,
etc.). 12 analyzed spots on granulite-facies domains give a weighted mean 207Pb/206Pb age of (2154±26) Ma (MSWD = 3.8), which is the best estimated age of granulite-facies metamorphism of this sample. The
weighted mean 207Pb/206Pb age of 5 analyzed spots on protolith zircon domains is (2714 ± 22) Ma (MSWD = 1.4), which represents the protolith forming
time. The discovery of ca. 3.4 Ga inherited zircon indicates that there are Palaeoarchean continental materials in this area.
The interpretation of formation conditions and the ages of zircons can be constrained by simultaneous in-situ analysis of trace elements and ages. 相似文献
190.
Yu?LiuEmail author Park?Won-Kyu Qiufang?Cai Seo?Jung-Wook Jung?Hyun-Sook 《中国科学D辑(英文版)》2003,46(10):1031-1039
Three tree-ring rainfall reconstructions from China and Korea are used in this paper to investigate the East Asian summer
monsoon-related precipitation variation over the past 160 years. Statistically, there is no linear correlation on a year-by-year
basis between Chinese and Korean monsoon rainfall, but region-wide synchronous variation on a decadal-scale was observed.
More rainfall intervals were 1860–1890, 1910–1925, and 1940–1960, and dry or even drought periods were 1890–1910, 1925–1940,
and 1960–present. Reconstructions also display that the East Asian summer monsoon precipitation suddenly changed from more
into less around mid-1920. These tree-ring precipitation records were also confirmed by Chinese historical dryness/wetness
index and Korean historical rain gauge data. 相似文献