S-wave velocity structure of upper and middle crust beneath the Three Gorges reservoir dam and adjacent region
-
摘要: 利用三峡数字地震台网记录的Sg波到时资料，采用地震层析成像技术，重建了三峡水库坝址及邻区中上地壳的三维速度图象，研究了地壳深部构造，主要结论是：① 黄陵背斜的岩性具有固结程度高、岩体均匀完整、埋藏深度至少达14 km的特征；② 秭归盆地与边缘构造由于岩层一致，而速度结构相同；构造变形的强度决定了秭归盆地及周缘区域沉积层的厚度分布和速度结构特征；③ 中上地壳中存在上地幔部分熔融物质，主要分布在秭归盆地和培石附近下方；④ 结晶基底的构造不均匀，顶面和底面起伏变化大，厚度和速度变化较大；⑤速度梯度带与重力梯级带位置一致，重力梯级带成因需要考虑深部构造和介质因素．
-
关键词:
- 三峡水库 中上地壳 S波速度结构
Abstract: A 3-D S-wave velocity structure of upper and middle crust beneath the Three Gorges reservoir dam and in adjacent region was reconstructed by means of the seismic tomography using the absolute Sg-arrivals from the earthquakes observed by the Three Gorges seismic network. Main research results of the crustal structure are as follows.①The lithology of the Huangling anticline is highly solidified, with uniformity and integrity. Its buried depth is not less than 14 km. ②The rock strata of the Zigui basin are consistent with that of its marginal region, so their velocity structures are the same. The depth distribution and velocity structure characteristics of the Zigui basin and its adjacent areas depended on the intensity of the tectonic deformation.③The partially molten substances, located in upper and middle crust and intruded from upper mantle,mainly distribute beneath the Zigui basin, as well as nearby the Peishi region.④The crystalline basement was constructed inhomogeneously, its top and bottom boundary, and the basement thickness and corresponding velocity structure, show significant regional variation.⑤The velocity gradient zone is generally consistent with the gravitational gradient zone. -
-
-
期刊类型引用(10)
1. 史哲，廖武林，姚运生，童广勤. 基于震相自动检测方法的秭归地区三维速度成像. 大地测量与地球动力学. 2024(12): 1280-1286+1311 . 
百度学术
2. 胡锦涛，谢军，危自根，金超. 三峡库区秭归段浅层速度结构和孕震环境. 地震学报. 2023(02): 223-233 . 本站查看
3. 张双喜，刘金钊，张品，陈兆辉. 联合BEMD和WMM方法实现位场多尺度边界检测. 武汉大学学报(信息科学版). 2022(04): 533-542 . 百度学术
4. 冯锐. 趣味地震学(5):诱发地震, 远非那么简单. 国际地震动态. 2019(05): 32-40 . 百度学术
5. 李伟，储日升，王烁帆. 2017年6月16日湖北秭归M_S4.3地震成因初探. 地震. 2019(03): 28-42 . 百度学术
6. 王杰，王秋良，黄颂，吴海波，赵凌云，陈俊华. 湖北巴东地区滑脱构造与地震活动特征. 大地测量与地球动力学. 2018(03): 225-232 . 百度学术
7. 张娜，赵翠萍，周连庆. 三峡水库区上地壳三维精细速度结构成像. 地震. 2018(04): 37-48 . 百度学术
8. 罗佳宏，马文涛. 三峡库区上地壳速度结构初步研究. 地震地质. 2016(02): 329-341 . 百度学术
9. 吴海波，王杰，杜承宸，申学林，陈俊华. 三峡库区上地壳S波衰减成像研究. 地震学报. 2016(02): 188-198+328 . 本站查看
10. 李小勇，朱培民，周强，彭松柏，刘江平，刘娇. 三峡库区上地壳横波速度结构. 地球科学(中国地质大学学报). 2014(12): 1842-1850 . 百度学术
其他类型引用(11)
计量
- 文章访问数: 2184
- HTML全文浏览量: 861
- PDF下载量: 163
- 被引次数: 21
下载:
