豫西南地区晚白垩世由北向南依次发育有桑坪盆地、夏馆盆地、西峡盆地、滔河盆地和李官桥盆地，呈北西向雁行式排列．通过分析控盆断裂特征，发现晚白垩世的活动断层具有明显的自相似性，分维值为1．2283，相关系数为0．999，这一分形特征产生的根本原因主要是晚白垩世秦岭造山带一级和二级活动在豫西南地区产状发生变化，产生具有分形特征的右行右阶羽状断裂的结果．由控盆断裂控制的晚白垩世盆地在形态上和沉积特征上都具有自相似特征，在盆地形态上，无论是单个小盆地，还是小盆地群的整体，都具有西部较窄、东部撒开的特点：在沉积特征上，无论是单个小盆地，还是小盆地群的整体，沉积中心平行并靠近于南部主控断裂，由西向东，沉积物粒度逐渐变细，沉积相逐渐由冲积扇相到曲流河相或滨浅湖相．这一认识对于分析晚白垩世盆地的沉积构造背景以及该时期秦岭造山带的大地构造性质，都具有重要的意义．%In Upper Cretaceous, southwestern Henan province, from north to south, successively exist Songpin basin, Xiaguan basin, Xixia basin, Taohe basin and Liguanqiao basin, all of those arrange north-west with YanHang type. With the analysis of characteristics of a basin-controlling fault, we found that active Upper Cretaceous faults are conspicuous selfsimilar with fractal value 1. 228 3 and Correlation coefficient 0. 999, and the primary cause of that is the attitude alteration of main active zones 1 and 2 of Qinling Orogen belt in south- western Henan province, and that the right order pinnate fracture of upper cretaceous turn up with fractalfer- ture. Upper Cretaceous basins controlled by fractures are provided with selfsimilarity in shape and in deposit characteristic. In shape, either single basin or a group of basins are narrower in west than in east; in deposit characteristic, either single basin or a group of basins are provided with depocenters closer to and parallel the south controlling fault, from west to east, the sediment granularity of those gradually are thinner, the sedimen- tary facies of those gradually change from alluvial to a meandering river or a littoral and shallow lake. The conclusion is important to the analysis of the sedimentary and tectonic background of Upper Cretaceous basin and geotectonic nature of temporal Qinling orogenic belt.
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