【摘要】 汶川大地震破坏性强,次生地质灾害严重。论文介绍了汶川大地震的地质构造背景与基本情况,以及作者对汶川大地震的发震构造、震后龙门山的地震安全期、成都-德阳-绵阳经济带的地震安全性及龙门山地震对川西油气聚散的影响等问题的认识。作者认为:(1)汶川大地震的发震构造可能是彭灌断裂而非普遍认为的北川-映秀断裂,(2)成-德-绵经济带中心城市市区范围内发生灾难性地震的可能性很小,这些城市的地震威胁依然主要来自龙门山,对来自龙泉山的地震威胁也应予以考虑;(3)地震可能造成了龙门山深层天然气的散失,但有利于川西坳陷裂缝性油气藏的形成;(4)龙门山的隆升演化与地震活动可能受制于西侧松潘-甘孜地块的推覆与东侧四川盆地的俯冲双向挤压力的作用。论文提出了从龙门山压缩应变能积聚与耗散均衡估算入手推算震后的地震安全期、利用油气生产井压力数据监测地应力变化、通过地震模拟计算定量评价成-德-绵经济带地震安全性等设想与建议。更多还原

【Abstract】 A devastating earthquake of magnitude 8.0 called Wenchuan earthquake struck Sichuan on May 12,2008.It resulted in huge casualties and property losses in the Longmen region of Sichuan and the southern Shaanxi and southern Gansu.The paper introduces the tectonic settings and the general situation of the Wenchuan earthquake.It presents the authors’ thought on the issues of the causative structure of the earthquake,the Longmen earthquake safety period after the earthquake,the earthquake safety of the Chengdu-Deyang-Mianyang economic zone,and the impaction of the earthquakes on the hydrocarbon accumulation and dissipation in West Sichuan.The authors put forward the following new opinions:(1) the causative structure of this earthquake may be the Peng-Guan fault,not the Beichuan-Yingxiu fault(central fault);(2) it is almost impossible for a devastating earthquake to occur in the urban areas of the Chengdu-Deyang-Mianyang economic zone;the main earthquake threat to these cities still comes from Longmen Mountains,and the menace from Longquan Mountains should also be taken into account;(3) the earthquake may lead to hydrocarbon dissipation in Longmen Mountains,but it may be favorable to the forming of the fractured reservoir and hydrocarbon accumulation in the West Sichuan depression;(4) The uplift of Longmen Mountains and the earthquakes in Longmen mountains may be controlled by the bilateral compressive forces from the Songpan-Ganzi block on the west side and Sichuan Basin on the east side.The authors put forward two tentative ideas: one is to estimate the rhythm of a strong earthquake in Longmen Mountains by calculating the balance between the accumulation and dissipation of the compressed strain energy,and another is to monitor the changes of the Earth stress in deep by using the pressure data measured from oil or gas producing wells.更多还原