赣东北元古代蛇绿岩Sm—Nd同位素年龄及地质意义   总被引：9，自引：0，他引：9  

邢凤鸣  徐祥  陈江峰  周禧泰  K.Afoland 《岩石矿物学杂志》1992,11(2):120-124

江南古陆东南缘赣东北弋阳—德兴—婺源一线有一条蛇绿岩带,普遍认为它是二个一级大地构造单元的分界线,形成于元古代。推断蛇绿混杂岩是元古代古洋壳俯冲时被挤上来的碎片;也有人认为它是中生代二大古陆之间的缝合线。Sm-Nd矿物等时线给出1034±16Ma(MSWD=1.0)的同位素年龄,它符合元古代缝合带的观点,而不利于中生代缝合带。  相似文献   

THE CONE OF DEPRESSION AND ITS USE IN SOLVING WATER PROBLEMS     

Edward J. Schaefer Hydraulic Engineer Ohio 《Ground water》1967,5(2):2-4

  相似文献   

Proposed GSSP for the base of Cambrian Stage 9, coinciding with the first appearance of Agnostotes orientalis, at Duibian, Zhejiang, China     

Loren E. BABCOCK  Gabriella BAGNOLI 《中国科学D辑(英文版)》2009,(4)

Exposed in natural outcrops near the Duibian Village, Jiangshan County, Zhejiang Province, China, the Duibian B section is proposed as the boundary stratotype for the base of an unnamed stage termed provisionally Cambrian Stage 9. The proposed position of the GSSP is 108.12 m above the base of the Huayansi Formation, at a horizon coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalis. This horizon coincides also with the first appearance of the cosmopoli-tan polym...  相似文献   

Observation Study on Precursory Geosound: Extraction of Nucleation Information in the Earthquake Preparation Process     

Zheng Zhizhen  Robert K. Vincent  Shen Ping  and Yang XuanhuiCenter for Seismic Data  Information  CSB  Beijing  China Bowling Green State University  Ohio -  USA Institute of Geophysics  CSB  Beijing  China 《中国地震研究》1999,(4)

In this paper, the observation networks of precursory geosound and observation instruments are introduced first. Then it is mentioned, in particular, that audible precursory geosound was instrumentally recorded for the first time. The following section discussed the relation between the geosound and earthquake. Finally, the Nucleation time in earthquake preparation process is discussed.  相似文献