Abstract Jurassic tectonism resulted in late Mesozoic intracontinental deformation of the North China Plate. A fold-and-thrust belt, related growth strata, and volcanic materials have been identified in the Jurassic Yungang Basin, which can be used to constrain the timing and scale of faulting and sedimentation. The age of volcanic materials in the growth strata and the sedimentary cycle of Jurassic strata indicate that the late Middle Jurassic Yungang Formation was the earliest sedimentary response to the onset of Jurassic deformation (i.e., the Yanshanian orogeny) from 170 to 160 Ma. Deformation involved detachment and fault propagation folding, which produced a marginal thrust belt and limb rotation of anticline. Restored cross-sections show that the northern basin experienced more intense shortening than the southern basin, consistent with field observations, possibly controlled by the Qifengshan strike-slip fault in the center of the fold-and-thrust belt. Fault striations, conjugate joints, and asymmetric folds show that the Yungang Basin underwent NW–SE-trending compression during the Middle–Late Jurassic. Therefore, we propose that the eastern Ordos Block was in a compressional setting during the Middle–Late Jurassic, due to flat subduction of the Paleo-Pacific Plate beneath the East Asian continent.

中文翻译：

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华北板块中部侏罗纪陆内变形：云冈盆地同构造沉积、构造地质和铀铅年代学的洞察

摘要 侏罗纪构造作用导致华北板块晚中生代陆内变形。侏罗系云冈盆地已发现褶皱冲断带、相关生长地层和火山物质，可用于限制断层沉积的时间和规模。生长地层中火山物质的年龄和侏罗纪地层的沉积旋回表明，晚中侏罗世云冈组是170~160 Ma侏罗纪变形（即燕山期造山运动）开始的最早沉积响应。变形涉及拆离和断层传播折叠，产生边缘逆冲带和背斜的肢端旋转。恢复的横截面显示北部盆地比南部盆地经历了更强烈的缩短，与野外观测一致，可能受褶皱冲断带中心的奇峰山走滑断裂控制。断层条纹、共轭节理和不对称褶皱表明云冈盆地在中晚侏罗世经历了 NW-SE 向挤压。因此，我们认为鄂尔多斯地块东部在中-晚侏罗世处于挤压环境，这是由于东亚大陆下方古太平洋板块的平坦俯冲。