An overview of the earth crust under China
An overview of the earth crust under China
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中国地壳概述
DOI：
10.1016/j.earscirev.2010.10.003
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发表时间：
2011
影响因子：
12.1
通讯作者：
Badal, Jose
中科院分区：
文献类型：
--
作者：
Zhang, Zhongjie;Yang, Liqiang;Teng, Jiwen;Badal, Jose
我们评价了近几十年来在中国进行的多次深地震测深的结果，并研究了由三个地台和15个褶皱系统组成的18个构造单元的地壳结构变化。收集了344个中、新生代沉积盆地的厚度资料和莫霍面深度资料，探讨了盆地厚度与各构造单元平均固结地壳厚度的关系。本文利用沉积盆地的深部地球物理资料，分析了中新生代沉积盆地与地幔顶部隆升的镜像对称性程度。通过对两个数据集应用标准的最小二乘分析方法，我们得到了每个地台和构造褶皱系统的平均固结地壳厚度和镜像对称因子，从而探索了沉积盆地底部和隆升地幔顶部深度之间的相关性。中国的固结地壳厚度在20-63公里之间，呈自东向西逐渐增厚的格局。用空间地震活动性和地震能量集中程度表示，根据地球顶部80公里地震震源的分配，该地区的流变性似乎不符合被广泛接受的大陆“果冻-三明治”模型，这种模型在中国看来似乎并不完全有效。镜像对称因子的研究结果表明，与其他构造单元相比，镜像对称因子主要在−0.5~−1.8的范围内变化。中国的大部分构造体系似乎是均衡补偿的。西藏是个例外，冈底斯-念青唐古拉(1.0)和喜马拉雅(0.1)褶皱系的对称性因子为正，表明这些构造带远未达到其他地区的均衡平衡。利用固结地壳的平均厚度和对称因子的绝对值，通过ln R=ln(h/|a|)的对数关系分析了其分带特征。关键发现是，无论地理位置如何，迄今已发现油气藏的沉积盆地的所有R=h/|a|值都落在19.38-37.40之间的窄值范围内。在涉及地壳厚度与对称系数之比的可能关系中有一些吸引力，当所获得的结果似乎表明是与油气藏有关的勘探实践的预测工具时，更是如此。
We assess the results of a number of deep seismic soundings performed in China over the last few decades, and study the variations in crustal structure in 18 tectonic units comprised of three platforms and 15 fold systems. Thickness data on 344 Mesozoic–Cenozoic sedimentary basins, as well as data on Moho depth are collected in order to discuss the relationship between the thickness of the basins and the average thickness of the consolidated crust in each tectonic unit. The degree of mirror-image symmetry between Mesozoic–Cenozoic sedimentary basins and the uplifting topmost parts of the mantle is herein analyzed using deep geophysical data on sedimentary basins. By applying standard methods of least-squares analysis to both datasets, we have obtained both the average thickness of the consolidated crust and the mirror-image symmetry factor for every platform and tectonic fold system, thereby allowing us to explore the correlation between the depths of the bottom of the sedimentary basins and the top of the uplifting mantle. The thickness of the consolidated crust in China is found to be between 20 and 63km, following a pattern of gradual thickening from east to west. Expressed in terms of spatial seismicity and the concentration of seismic energy, and according to the sharing-out of earthquake hypocenters in the top 80km of the earth, the rheology of the area does not appear to suit the widely accepted “jelly–sandwich” model for the continents, which does not seem to be entirely valid in China. The findings on the mirror-image symmetry factor show that this parameter varies mainly in the range −0.5 to −1.8 compared with each other tectonic unit. Most of the tectonic systems in China appear to be isostatically compensated. Tibet is an exception, in that the symmetry factor is positive for the Gangdise–Nyainqentanglha (1.0) and Himalayan (0.1) fold systems, implying that these tectonic zones are far from being in the isostatic equilibrium of the other regions. We have also analyzed the zoning characteristics through the logarithmic relationship ln R=ln (h/|a|), using the average thickness of the consolidated crust and the absolute value of the symmetry factor. The key finding is that regardless of geographical location, all the values of R=h/|a| for those sedimentary basins in which oil/gas reservoirs have to date been found, fall into the narrow range of values between 19.38 and 37.40. There is some appeal in a possible relationship involving the ratio of crustal thickness to symmetry factor, more so when the results obtained appear to suggest a prognostic tool for exploratory practice in relation to oil/gas reservoirs.
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影响因子：
2.9
作者：
Z. Zhao;B. Windley
通讯作者：
Z. Zhao;B. Windley
影响因子：
2.9
作者：
Zhongjie Zhang;J. Badal;Yinkang Li;Yun Chen;Li‐Qiang Yang;J. Teng
通讯作者：
Zhongjie Zhang;J. Badal;Yinkang Li;Yun Chen;Li‐Qiang Yang;J. Teng
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift
影响因子：
2.9
作者：
Mingjun Liu;W. Mooney;Songlin Li;N. Okaya;S. Detweiler
通讯作者：
Mingjun Liu;W. Mooney;Songlin Li;N. Okaya;S. Detweiler
DOI：
10.1002/cjg2.1348
发表时间：
2009
期刊：
Chinese Journal of Geophysics
影响因子：
--
作者：
J. Teng;Fu-yun Wang;Wenqing Zhao;Jin-ren Zhao;Ming Li;Xiaobo Tian;Yafen Yan;Yongqi Zhang
通讯作者：
J. Teng;Fu-yun Wang;Wenqing Zhao;Jin-ren Zhao;Ming Li;Xiaobo Tian;Yafen Yan;Yongqi Zhang