摘要
本文从盐层及盐上层碎屑岩厚度出发 ,讨论了在盐 (蒸发岩 )参入变形条件下 ,前陆区变形前缘盐上层构造样式。盐层及盐上层相对厚度决定着盐上层基本变形样式———褶皱或断裂。当盐上层背斜虚脱空间面积小于或等于变形前相应长度盐层所对应的盐面积时 ,盐上层形成完整背斜 ;反之 ,盐上层发生断裂。在发生断裂条件下 ,相背断层的交切情况决定着盐上层的构造样式 :当交切点在盐上层下部外面时 ,形成突起构造 ;当交切点在盐上层内部时 ,则形成上部突起构造与下部三角带相叠加的情况或形成鱼尾构造 ;当交切点在盐上层外面时 ,则形成三角带构造。交切点的位置主要决定于岩上层的厚度。
Structural styles and their relationships in thedeformation leadingedge of the evaporite-bearing foreland basin fill are discussed based on the thickness of the evaporite layer and its overburden. The basic structural styles of the overburden, i.e., fold or fault, are determined by the relative thicknessbetween the overburden and the evaporite layer. Where the area in core of a detachment fold is smaller than or equal to the area of evaporite available to supply core of the fold, an anticline will form. Where the area in core of a detachment fold is larger than the area of the evaporite available to supply core of thefold, faults will form. As for the la-ter, the structural styles are controlledby the intersection position of two back thrust faults. Where two back thrust faults intersect within or under the evaporite layer, a pop-up will form. Where two back thrust faults intersect within the overburden, a pop-up will form abovethe intersection and a triangle with partial overburden sequence will form underthe intersection. Where two back thrust faults intersect above the overburden, atriangle zone with a complete overburden sequence will form. The position of the intersection is determined by the thickness of the overburden.
出处
《地球学报》
EI
CAS
CSCD
北大核心
2004年第5期561-564,共4页
Acta Geoscientica Sinica
基金
国家自然科学基金项目 (编号 :40 172 0 76)
国家重点基础研究发展规划项目 (编号 :G19990 43 3 )资助。
关键词
构造样式
盐层
褶皱
断裂
evaporite foreland leading edge of deformation structural style
