【摘要】 通过浅层地震勘探、钻孔联合剖面分析、野外地貌调查以及新地质年代测定等技术方法,对原先认定的郑州老鸦陈断裂的活动性开展调查.其中,浅层地震勘探结果表明,该断裂仅存在于新近纪以前的地层,而在新近纪地层内均未发现该断层错断和活动迹象.同时,地表的地质地貌调查亦发现"地貌陡坎"与老鸦陈断裂的位置不一致.另外钻探和钻孔联合剖面的分析也表明,地表的陡坎仅发育在马兰黄土中,其下地层平缓,没有错断现象,认为该陡坎的形成与老鸦陈断层没有关系,但可能与黄河改道变迁的侵蚀作用有关.因此,老鸦陈断裂不属于活动断裂.更多还原

【Abstract】 Activity of the Laoyachen fault, which was previously recognized as an active fault, is investigated by means of shallow seismic exploration, borehole composite profile analysis, geomorphologic survey and geological dating. The seismic exploration result indicates that this fault only appears in the strata before Neogene, while it has not cut through the Neogene strata themselves. The surface geological and geomorphologic survey show that the position of so-called "fault scarp" is not consistent with the outcrop of the Laoyachen fault. Moreover, the result of drilling and borehole composite profile analysis denotes that the scarp only grew in the Malan Loess, and the strata below kept gentle without offsetting. We think that the formation of this scarp may be associated with the course change of the Yellow River, rather than being related to the motion of the Laoyachen fault. Therefore, the Laoyachen fault is not an active fault.更多还原