破裂大陆岩石圈科学计划探索

EXPLORING FOR THE "RUPTURING CONTINENTAL LITHOSPHERE" PROGRAMS

大陆边缘是研究岩石圈破裂及洋壳开始扩张的重要场所,破裂大陆岩石圈(RCL)是美国大陆边缘计划(MARGINS)围绕大陆边缘岩石圈破裂这一地质过程而实施的一项科学计划。阐述了RCL研究的主要科学问题,详细地介绍了其所采用的科学研究方法和长远计划。RCL主要利用地球物理数据,在全球及局部板块运动背景下,结合地球化学、岩石力学、地热、地磁学等方法,建立地层沉积沉降史及岩石圈破裂扩张模型,最终对其形成机制、岩石圈扩张驱动力以及扩张期间内部各系统的演化等问题进行解释。最后以加利福尼亚湾地区为例阐述了RCL的具体研究情况及存在问题。

Continental margin marks the principal locus of past and present lithospheric deformation. ＂Rupturing Continental Lithosphere＂ plans, focusing on the geological process of the continental rifting, are mainly promoted by American MARGINS workshop. This paper expatiates on the principal problems and the methods in research. RCL programs will establish the extension modeling for continental lithosphere and the sedimentation history, using all kinds of geophysical data and with the help of geological, geochemical, petrological and geodetic studies, and make reasonable interpretation to the forming mechanism, the driving forces of rifting initiation, and the evolvement of the thermo-mechanical systems and so on. In the end, this paper takes the research on the California/Salton Trough as an example to illuminate the methods and questions in ＇RCL＇ programs.