[关键词]
[摘要]
临潼-长安断裂是渭河盆地内西安凹陷与骊山凸起的分界断裂,该断裂东北段位置和走向清楚,但西南段(神禾塬以西)的推测走向并无实证资料。在临潼-长安断裂西南方向延伸区域内,通过对3 条总长近27km 的人工地震勘探剖面解译,发现均存在北倾断裂异常,在其中1 处异常布置的地质钻探剖面显示,上更新统和中更新统地层存在错断现象。这些勘探异常点被认为是临潼-长安断裂带中的最北侧断裂FN,其连线基本在1 条线上,以大约SW240°的方向,延续了临潼-长安断裂带中段走向,继续向西南方向延伸。
[Key word]
[Abstract]
The Lintong-Chang’an fault,one of active faults in the Weihe basin,is a boundary fault between Xi’an sag and the uplift of the Lishan mountain. The fault position and strike in the northeastern section is clear because of the fault scarp geomorphic characteristics. In the southwest section (west of Shenhe plateau),however,the surrounding landform is flat terrain formed by late Pleistocene alluvial fan,and hasn’t any fault geomorphological features. The position and strike of the fault on preceding knowledge in this area was based on some speculations,not supported by any evidence data. In order to study Lintong-Chang’an fault location and direction in the southwest direction within the region,three seismic prospecting lines with a total length of nearly 27km and one geological drilling profile were carried out. The seismic interpretation shows that an anomaly,north dipping fault,presents in all prospecting profiles. The geological drilling profile,arranged in one abnormal place,reveals that discontinuity exists in the upper Pleistocene and Middle Pleistocene strata. These prospecting abnormal points locating basically along a straight line are considered to be the north fault of Lintong-Chang’an fault zone, FN. It goes in direction with approximately SW240°,continuation of the Lintong-Chang’an fault zone in the middle section,and continues to extend to the southwest.
[中图分类号]
[基金项目]
国家自然科学基金(40972215)和西安市地下铁道有限公司(D6-KC-062013001)共同资助