| 京津唐地区地壳结构与强震的发生──Ⅱ．S波速度结构 |
| |
| 引用本文： | 孙若昧,赵燕来.京津唐地区地壳结构与强震的发生──Ⅱ．S波速度结构[J].地球物理学报,1996,39(3):347-355. |
| |
| 作者姓名： | 孙若昧 赵燕来 |
| |
| 作者单位： | 1. 中国科学院地球物理研究所, 北京 100101;
2. 国家地震局分析预报中心, 北京 100036 |
| |
| 基金项目： | 国家地震局“八五”科技攻关项目 |
| |
| 摘 要： | 利用１９８６－１９９３年发生在京津唐地区的２５１６个地震的２１９２７个Ｓ波到时进行层析成像，得出：（１）公元１０００年以来研究区强震震中在下地壳的投影大多分布在低速块体内或低速块体与高速块体相交地带偏低速块体的一侧；（２）唐山地震震源下方的物质，波速比Ｖｐ／Ｖｓ呈现高值，推测呈部分熔融状态，有热物质流从莫霍界面的下方沿通向震源下方的断裂入侵的迹象。（３）黄骅坳陷中心区的上地壳呈现低Ｖｐ／Ｖｓ值，推测那里为水－汽转变的地热系，这与在该地区所测量的高热流值一致。冀中坳陷区的高Ｖｐ／Ｖｓ值反映出其地下物质可能呈部分熔融状态。
|
| 关 键 词： | S波层析成像 京津唐地区 强震 |
| 收稿时间： | 1994-11-23 |
CRUST STRUCTURES AND STRONG EARTHQUAKES IN THE BEIJING, TIANJIN, TANGSHAN AREA: II. S WAVE VELOCITY STRUCTURE |
| |
| SUN RUO-MEI, ZHAO YAN-LAI, WU DAN.CRUST STRUCTURES AND STRONG EARTHQUAKES IN THE BEIJING, TIANJIN, TANGSHAN AREA: II. S WAVE VELOCITY STRUCTURE[J].Chinese Journal of Geophysics,1996,39(3):347-355. |
| |
| Authors: | SUN RUO-MEI ZHAO YAN-LAI WU DAN |
| |
| Affiliation: | 1. InsTitutE of Geophysics, Academia Sinica, Beijing 100101, China;
2. Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China |
| |
| Abstract: | By using of 21 927 S arrival times of 2516 events, which occurred within the Beijing, Tianjing and Tangshan areas during 1986-1993, we carried out tomographic inversion. The results are: 1. The projection places of strong earthquakes since 1000 year on the image of the lower crust distribut within low velocity blocks or in transitional zones between high and low velocity areas, especially at edges of low velocity blocks. 2. Under the hypocenter of the Tangshan earthquake there are high Vp/Vs values, which are suggestive of a partially molten volume. There is an evidence, that hot material is upwelling through a fault from Moho to the hypocenter. 3. The central part of the Huanghua depression has low Vp/Vs values, which inferring a geothermal system near the water-stream transition in concert with the observed high heat flow values. High Vp/Vs values in the Jizhong depression might be exhibited by partially molten magma bodies. |
| |
| Keywords: | S wave tomography Beijing Tianjin and Tangshan areas Strong earthquake |
| 本文献已被 CNKI 维普 等数据库收录！ |
| 点击此处可从《地球物理学报》浏览原始摘要信息 |
|
点击此处可从《地球物理学报》下载全文 |
|
