| 川滇菱形地块的应变能积累释放周期和强震预测 |
| |
| 引用本文： | 许昭永,文丽敏,石宝文,许峻,樊俊屹,李正媛,苏有锦.川滇菱形地块的应变能积累释放周期和强震预测[J].地震学报,2015,37(5):774-786. |
| |
| 作者姓名： | 许昭永 文丽敏 石宝文 许峻 樊俊屹 李正媛 苏有锦 |
| |
| 作者单位： | 1.中国昆明 650091 昆明南方地球物理技术开发有限公司 |
| |
| 基金项目： | 国家重点基础研究发展(973)计划项目2013CB733200云南省教育厅科学研究基金项目2012C110 |
| |
| 摘 要： | 将川滇菱形地块分为两个地块， 分别以形变确定应变速率、 深部速度构造确定弹性模量、 联合地块体积确定地块应变能积累与时间的关系， 结合历史强震研究应变能积累释放周期以及该周期内的强震活动， 进而研究应变能积累释放与强震活动的关系. 结果表明， 地块应变能积累释放存在周期性并可预测强震震级. 在应变能积累前期， 没有强震(M≥7.0)发生； 随着时间增加， 应变能继续增加， 地块上先后发生几次强震， 但每次强震震级均小于预测震级， 即一次强震只释放了一部分能量； 而后应变能积累继续增加， 直到一、 二次特大强震(M≥7.5)发生， 将绝大部分应变能释放. 至此， 老的周期结束， 新的周期开始. 应变能积累从小到大直到最后完全释放的周期性导致了地震的平静活跃周期， 地震活跃期比平静期长得多. 本文认为， 大区域地理范围因其含有多个地块， 不宜讨论其地震平静活跃周期， 而对于小范围单次强震也不宜讨论其复发周期. 虽然活跃期中的强震从时间上看并无任何规律， 但利用活动地块应变能的积累释放曲线所预测的震级与实际震级很接近. 本文结果对于地震安全性评价工作可能有重要意义.
|
| 关 键 词： | 活动地块 应变能 积累释放周期 强震活动 地震预测 |
| 收稿时间： | 2014-09-04 |
The strain energy accumuIating-reIeasing period and strong earthquake prediction in Sichuan-Yunnan rhombic bIock |
| |
| Affiliation: | 1.Kunming Southern Geophysical Technology Co., Ltd, Kunming 650091， China2.School of Resource Environment and Earth Sciences, Yunnan University, Kunming 650091, China3.China Earthquake Networks Center, Beijing 100045, China4.Earthquake Administration of Yunnan Province, Kunming 650224, China |
| |
| Abstract: | In this paper, the Sichuan-Yunnan rhombic block is divided into two parts. The strain rate is achieved by deformation, the elastic modulus is acquired by velocity structure in the deep, the volume of the block is calculated by the area and thickness of block, and then the variation of accumulated strain energy with time is confirmed. On this basis, combined with the research of historical strong earthquakes, the relationship between the period of energy accumulating-releasing and the seismic activity is obtained. The results show that the strain energy accumulating-releasing emerges periodically, which can be used for strong earthquake prediction. The strong earthquakes (M≥7.0) do not occur at initial stage of strain energy accumulation. The strain energy increases continuously with time and then several strong events occur firstly, but each event is smaller in magnitude than the predicted ones, i.e., one event releases a small part energy and later energy increases incessantly. The energy is not completely released until one or two great strong events (M≥7.5) occur. Thus, the old cycle ends and a new cycle starts. Obviously, the quiet to active periods are caused by the cycle of strain energy accumulation from small to great, and then to completely releasing. Active stage is much longer than the quiet one. Therefore, it is unsuitable to discuss the quiet-active period for a great geographic area covered by many blocks or to discuss the repeat period of single strong earthquake for a small region. Although the occurrence of strong earthquakes does not obey any law in time, the magnitude predicted by the strain energy accumulating-releasing curves is coincident with the real one, which may be significant for seismic safety evaluation. |
| |
| Keywords: | |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《地震学报》浏览原始摘要信息 |
|
点击此处可从《地震学报》下载全文 |
|
