青海共和7.0级地震与龙羊峡水库关系探讨

DISCUSSION ON RELATION BETWEEN GONGHE M_S(7.0) EARTHQUAKE AND LONGYANGXIA RESERVOIR

龙羊峡水库建于青海省共和盆地内，大坝围堰拦洪期间，于1981年11月23日在坝址附近发生最大震级MS2．3的小震活动，当时坝前壅水高度为39m。1986年11月大坝截流蓄水后约3年半，于1990年4月26日在距库尾约40km处发生MS7．0级地震，其后至1994年10月发生MS≥5级地震多次，且有震中逐渐靠近水库的趋势。共和7．0级地震引起了地震界特别是水库地震研究者的广泛关注。我们根据已发表的有关资料以及研究成果，初步认为共和7.0级地震及其后一段时间内发生的地震应属构造地震；而1994年发生的≤6级地震，既与7.0级地震有关，但主要与龙羊峡水库蓄水有关。

Longyangxia Reservoir was built in the Gonghe basin of Qinghai province. Near the dam of that,small earthquake activities which maximum magnitude was MS2.3 have occurred on November 23,1981, just as the damming up level was 39 m. After impounding in November, 1986 the M7.0earthquake occurred at a distance 40km from the dam on April 26, 1990, since then until October,1994 the MS≥5. 0 earthquakes many a time have occurred, and the epicentral Angration tendance appeared to be adjacent to the dam progressively. The Gonghe MS7.0 earthquake has caused widespread the parties concerned to follow wtth interest. Based on the informations concerned, the Gonghe MS7. 0 earthquake and that occurred for some time since then are primarily recognized to belong iri tectonic earthquake, while the MS≤6.0 earthquake in 1994 was correlated with the MS7. 0that,but wtth the impoundment of Longyangxia reservoir mainly.