太原盆地构造格局及其与地震活动水平的新认识
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摘要
太原盆地存在两组断裂，一组为横向断裂，即北东东－东西向断裂，是燕山期或晚古生代的断裂，其中有些断裂在上新世初仍有活动，但活动的幅度和规模均较小；另一组为纵向断裂，即北北东－北北西向断裂，为上新世－第四纪断裂，活动性较强，但规模不大，太原盆地的中小地震可能与之有关。经断裂分析，太原盆地不是裂谷盆地，而是晚新生代的沉积盆地。山西的发震构造主要是晚新生代的裂谷盆地，因此提出太原盆地不致发生强震，只有发生中小地震的背景。由于太原盆地介于裂谷盆地之间，邻区发生的强震可影响到太原盆地，震害也较重。因之在地震活动期内也不能轻易放松警惕。
There are two groups of faults in Taiyuan basin. The one, occurs in Mesozoic or Late Palaeozoic, is classified as cross faults in NEE-EW trending, some of which activated at Early Pliocene, but in small scale and intensity. the other, occurs in Pliocene-Quaternary, is longitude faults in NNE-NNW the small-mid scaled earthquakes in Taiyuan basin are associated. Fault analysis show that Taiyuan basin is sedimentary basin of Late Cenozoic rather than rifted one. The primary earthquake-derived structure is Late Cenozoic basin, therefore strong earthquakes tend not to occur in Taiyuan basin. However, adjacent strong earthquakes affect Taiyuan basin and possibly cause great loss since it is confided by rifted basins.
There are two groups of faults in Taiyuan basin. The one, occurs in Mesozoic or Late Palaeozoic, is classified as cross faults in NEE-EW trending, some of which activated at Early Pliocene, but in small scale and intensity. the other, occurs in Pliocene-Quaternary, is longitude faults in NNE-NNW the small-mid scaled earthquakes in Taiyuan basin are associated. Fault analysis show that Taiyuan basin is sedimentary basin of Late Cenozoic rather than rifted one. The primary earthquake-derived structure is Late Cenozoic basin, therefore strong earthquakes tend not to occur in Taiyuan basin. However, adjacent strong earthquakes affect Taiyuan basin and possibly cause great loss since it is confided by rifted basins.
引文
1赵永贵，蔡祖煌主编．岩溶地下水系的研究—以太原地区为例．北京：科学出版社，19902郑鹄．太原区域地质构造及地震活动特点．山西地震，1984（3）3杨承先．活动断裂鉴定中常见的假象与误解．见：地壳构造与地壳应力文集（4），北京：地震出版社，19904徐锡伟，邓起东，尤惠川．山西系舟山西麓断裂右施错动证据及全新世滑动速率．地震地质，1986．8（3）5李时毓，施树江．对太原盆地活动性断层分析．勘察科学技术，1987（2）6江娃利等，山西省交城断裂全新世活动证据及第四纪活动历史．见。地壳构造与地壳应力文集（6），北京：地震出版社，1993
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