摘要
走滑断裂体系中经常发育里德尔剪切的断裂组合,世界上不同构造背景下与走滑断裂相关的盆地(走滑盆地)也很多见。因此里德尔剪切是地质构造研究中的重要方面。我们从三个方面对里德尔剪切的节理构造组合及盆地组合进行了对比:(1)里德尔剪切构造组合与比例尺无关。里德尔剪切带的(转换)拉张区与沉积盆地的分布区是相似的;(2)断裂的最大位移区与断陷盆地的沉积中心是一致的,断陷盆地长轴平行于断裂走向;(3)物理模拟试验及数学模拟试验都证实了走滑盆地的演化。基于上述认识,我们通过厘米级岩芯标本的观察,结合已发表的盆地资料,提出了6类与里德尔剪切有关的构造组合及断陷盆地组合。(1)雁列状构造及盆地组合:许多盆地发育雁列状构造。同时,与里德尔剪切相关的雁列状盆地的宽度与主剪切断裂的剪切位移呈正相关。(2)帚状或马尾状构造及盆地组合:二者在形态上相似,所以归为一类。成因上,马尾状构造及盆地主要发育在走滑断裂的拉张端部,而帚状构造或盆地反映走滑断裂的旋扭作用,可以在走滑断裂影响区域的任何部位。(3)串珠状构造及盆地组合:该类型的盆地主要是指释压盆地的组合,拉分盆地也可以形成串珠状盆地。(4)S状或Z状构造或盆地组合:左行走滑形成Z状构造或盆地,而右行走划形成S状构造或盆地。(5)多字型构造及盆地组合:是拉分盆地的典型组合,可以过渡到串珠状盆地。(6)复杂的网状构造及盆地组合:通常是由于分布型简单剪切的作用结果。以上盆地组合类型包括大型盆地内次级单元(次级盆地或更次级盆地)的组合,但不包括多成因、多期活动的构造及盆地。
The importance of strike slip faulting was recognized near the turn of the century. Riedel shear patterns are commonly observed in the strike slip fault systems. The basins related to Riedel shear are also documented in different tectonic settings in the world. This paper reviews the characteristics and evolution of Riedel shears in terms of mechanism of simple shear. Based on the data of the core samples at the centimeter scale and the published data about sedimentary basins in nature, the aim of this paper is to propose some patterns of sedimentary basin related to Riedel shears. Results： Three evidences show that the Riedel shear pattern is similar to the faulted basin pattern in a strike- slip fault zone. （1） The pattern of Riedel shears is not dependent on the scale observed. The extensional （transtensional） zones in the small strike-slip faults are similar to the basin distributions along large fault zone; （2） The depocenter along a fault is the same as the location of maximum fault displacement ; The basins commonly show elongated form as the faults. （3）The basins related to Riedel shears can be reproduced by physical and numerical experiments. Based on above factors, we proposed six patterns of sedimentary basin related to Riedel shears： en echelon basin, horsetail basin, beaded basin, S-type （Z-type） basin, G-type basin, and complicated lattice basin. （1） The width of en echelon basins increases with the increase of shear displacement in the principal shear zone. （2） Geometry of horsetail basins and brush basins are similar to each other. The horsetail basins are generally found in the extensional tip zones of a strike-slip fault, whereas the brush basins develop in any place in a shear zone. （3） Beaded basins are formed due to extension of releasing zones in the braided strike-slip fault. Individual basin is in the form of lenses. （4） Z-type basins are formed due to sinistral shear and S-type basins are formed due to dextral shear. （5） ξ-type basins are typic
出处
《地质论评》
CAS
CSCD
北大核心
2017年第2期287-301,共15页
Geological Review
基金
墨西哥自然基金资助项目(编号:08967)
中国石油化工股份有限公司石油勘探开发研究院项目(编号:GSYKY-B09-32)的成果~~
