裂变径迹对豫西宜阳地区中新生代构造演化过程的约束

为了研究宜阳地区与鄂尔多斯盆地中新生代构造演化过程的时空关系，对宜阳地区开展了锆石、磷灰石裂变径迹测年分析。结果表明，锆石裂变径迹年龄为185±8 Ma，磷灰石裂变径迹年龄为49±3 Ma～41±3 Ma，结合前人资料，认为宜阳地区中新生代以来共经历了两期较大规模的构造改造，分别是晚三叠世—早侏罗世印支运动和始新世—渐新世喜马拉雅运动对本区的影响。这两期构造运动与鄂尔多斯三叠纪原型盆地萎缩及秦岭造山带快速造山均有很好的等时性，说明宜阳地区与鄂尔多斯盆地自中生代以来具有相似的构造背景。

Constraints of tectonic evolution of Mesozoic and Cenozoic in Yiyang area of western Henan by fission track

This paper is analysised by zircon and apatite fission track dating, in order to study thespatiotemporal relationship between the Mesozoic and Cenozoic tectonic evolution in theYiyang area and the Ordos Basin. The results show, zircon fission track age is 185±8 Ma,Apatite fission track age is 49±3 Ma～41±3 Ma. Combined with previous data, this paper isconsidered there are two large-scale structural transformations have been experienced inYiyang area since the Mesozoic and Cenozoic, which are correspond the influence of theIndo-Chinese Movement in Late Triassic-Early Jurassic and the Himalayan Movement inEocene-Oligocene. The tectonic movements in these two phases have a good isochronism withthe shrinkage of the Ordos Triassic prototype basin and the rapid orogeny of the Qinlingorogenic belt, and shows that the Yiyang area and the Ordos Basin have similar tectonicbackgrounds since the Mesozoic.