|
|||||
|
|
| GPS观测的2001年昆仑山口西MS8.1级地震地壳变形 | |
| 引用本文： | 任金卫,王敏.GPS观测的2001年昆仑山口西MS8.1级地震地壳变形[J].第四纪研究,2005,25(1):34-44. |
| 作者姓名： | 任金卫 王敏 |
| 作者单位： | 1. 中国地震局地震预测研究所,北京,100036;中国地震局地质研究所地震动力学国家重点实验室,北京,100029 2. 中国地震局地震预测研究所,北京,100036 |
| 基金项目： | 科技部社会公益研究项目 |
| 摘 要： | 2001年11月14日17时26分,在昆仑山口西青海和新疆交界处发生了MS8.1级强烈地震。震后利用 GPS开展了相对密集的地壳形变观测。计算获得的同震位移表明,地震地壳形变影响范围大致为88°～97°E, 32°～38°N,断层运动具有明显的左旋兼挤压的特点。在昆仑山口附近GPS观测获得的地表破裂两侧的相对左旋 位移量约为2.6m,与地表野外调查获得的该处的地震破裂位移值符合的很好。断裂南侧垂直断裂走向同震位移 量逐渐衰减,位移方向相对稳定。而断裂北侧,同震位移主要集中分布在柴达木盆地南缘,位移方向变化较大,盆 地内部位移量迅速衰减,表明东昆仑断裂北侧柴达木盆地地壳介质性质与其南侧高原腹地有明显不同。GPS观测 得到的震后断层蠕动结果表明,最初两周内断层蠕动位移量就占了观测期(近1年时间)总位移量的47%还要多, 其后半年多的时间内断层蠕动位移量不到观测期总位移量的40%,而余下的近5个月时间断层蠕动位移量只占观 测期总位移量的13%。断层蠕动速率在最初两周内超过130cm/a,到2002年3月11日迅速下降到26cm/a,其后 则逐渐呈线性衰减。区域GPS观测的初步结果同时表明,尽管地震破裂附近断层两侧有较大的相对位移,但东部 甘青川一带相关断层上相对运动不明显,可能说明这一区域仍处在 |
| 关 键 词： | 地震 地壳变形 GPS 青藏高原 |
| 文章编号： | 1001-7410(2005)01-34-11 |
| 收稿时间： | 2004-05-18 |
| 修稿时间： | 2004年5月18日 |
GPS MEASURED CRUSTAL DEFORMATION OF THE MS8.1 KUNLUN EARTHQUAKE ON NOVEMBER 14th 2001 IN QINGHAI-XIZANG PLATEAU |
|
| Ren Jinwei,Wang Min.GPS MEASURED CRUSTAL DEFORMATION OF THE MS8.1 KUNLUN EARTHQUAKE ON NOVEMBER 14th 2001 IN QINGHAI-XIZANG PLATEAU[J].Quaternary Sciences,2005,25(1):34-44. | |
| Authors: | Ren Jinwei Wang Min |
| Institution: | 1. Institute of Earthquake Science, China Earthquake Administration, Beijing 100036; 2. State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029 |
| Abstract: | On November 14th 2001 an earthquake with magnitude of M S 8.1 occurred at the northern Qinghai-Xizang Plateau in China. 58 old GPS stations at the surface rupture and the surrounding areas were re-set up after the earthquake and new GPS measurements were carried out to compare with old GPS measurements took several years before the earthquake. 16 new stations were also established immediately after the earthquake across the surface rupture, among them 4 has been continuously observed and the rest have been measured six times since December 2nd 2001. The co-seismic displacements calculated by GPS measurements show that while the deformation caused by the earthquake is in an area within 88°～97°E and 32°～38°N, much of the deformation was restricted along the surface ruptures. The fault movement was left-lateral strike-slip with compressional components. Near the Kunlun Pass the GPS measured displacement is about 2.6m which is close to the displacement investigated on site. The co-seismic displacement south to the surface rupture is decreasing gradually and the direction of the displacement is relatively consistent, while the displacement north to the surface rupture is concentrated along the southern edge of the Qaidam Basin and the displacement decreased rapidly within the basin, showing crust property difference between the Qaidam Basin and the interior of the Qinghai-Xizang Plateau. The preliminary result from the GPS measurements has shown that the creeping displacement across the rupture is more than 47% of the total for the first two weeks, and the creeping rate decreases rapidly afterwards, showing the rheological property of the deformed crust in that area of the Plateau. There is no obvious relative movement along the faults east to the surface rupture which shows that faults in this area may still be locked. |
| Keywords: | GPS |
| 本文献已被 CNKI 万方数据 等数据库收录！ | |
| 点击此处可从《第四纪研究》浏览原始摘要信息 | |
| 点击此处可从《第四纪研究》下载免费的PDF全文 | |