• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Tectonophysics: International Journal of Geotectonics and the Geology and Physics of the Interior of the Earth >Fracture analysis and determination of in-situ stress direction from resistivity and acoustic image logs and core data in the Wenchuan Earthquake Fault Scientific Drilling Borehole-2 (50-1370m)
【24h】

Fracture analysis and determination of in-situ stress direction from resistivity and acoustic image logs and core data in the Wenchuan Earthquake Fault Scientific Drilling Borehole-2 (50-1370m)

机译：汶川地震断层科学钻探二期（50-1370m）电阻率，声波测井和岩心数据断裂分析与地应力方向确定

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

After the Wenchuan Earthquake on May 12th, 2008, the Wenchuan Earthquake Fault Scientific Drilling Project (WFSD) was initiated in order to investigate the structure of the fault zones and the mechanism of the earthquake. The WFSD contains four boreholes (WFSD-1, WFSD-2, WFSD-3 and WFSD-4) lying at the maximum displacement locations along the Yingxiu-Beichuan fault zone and the Guanxian-Anxian fault zone, and WFSD-2 is the second borehole and is still being drilled. Core samples, resistivity and acoustic image logging data were acquired from 50 to 1370m. The natural fractures, borehole breakouts, drilling-induced fractures and drilling-enhanced natural fractures were identified from the cores and the image logs and were statistically analyzed. The strikes of the natural fractures systematically vary and can be sorted into four groups according to depth: (1) above 637m, mainly striking ENE-WSW; (2) in the interval of 637-932.6m, striking NNE-SSW; (3) in the interval of 932.6-1200m, directed ENE-WSW then to WNW-ESE, while striking NE-SW from 1030m to 1150m; (4) from 1200m to 1370m, maintaining a strike of WNW-ESE. The natural fractures from 50m to 637m seem to be reverse faults which strike approximately parallelly to the main fault. Two sets of conjugate fractures around 1002.4m indicating subvertical maximum principal paleo-stress direction may be a subordinate structure of the main fault caused by a local stress field, and it reveals the complex stress field of Yingxiu-Beichuan fault zone when the fractures formed. A total of 12 BOs, 2 sets of DIFs and one set of DEFs with an overall length of 30.4m were interpreted from 960m to 1370m in WFSD-2. The average SHmax orientation interpreted for WFSD-2 (960-1370m) is 120.7°-300.7°N (i.e. WNW-ESE) with the standard deviation of 9.2° and it is consistent with the stress status of Yingxiu-Beichuan fault zone which is one of the main fault zones in the 2008 Wenchuan Earthquake.
机译：2008年5月12日汶川地震发生后，汶川地震断层科学钻探项目（WFSD）启动，目的是调查断层带的结构和地震的机理。 WFSD包含四个钻孔（WFSD-1，WFSD-2，WFSD-3和WFSD-4），它们位于沿映秀-北川断裂带和关县-安县断裂带的最大位移位置，而WFSD-2是第二个井眼，仍在钻探中。采集了50至1370m的岩心样本，电阻率和声波图像测井数据。从岩心和图像测井资料中识别出天然裂缝，井眼破裂，钻井引起的裂缝和钻井增强的自然裂缝，并进行了统计分析。天然裂缝的走向系统地变化，可以根据深度分为四类：（1）637m以上，主要是ENE-WSW; （2）在637-932.6m的范围内，撞击NNE-SSW; （3）在932.6-1200m的范围内，将ENE-WSW引向WNW-ESE，同时将NE-SW从1030m打击至1150m; （4）从1200m至1370m，维持WNW-ESE的走向。从50m到637m的天然裂缝似乎是反向断裂，其走向与主断裂大致平行。 1002.4m左右的两组共轭裂缝表明局部主应力场是次垂直最大主应力方向，可能是主断裂的从属结构，当裂缝形成时揭示了映秀-北川断裂带的复杂应力场。在WFSD-2中，从960m到1370m解释了总共12个BO，2个DIF和1个DEF，总长度为30.4m。 WFSD-2（960-1370m）的平均SHmax取向为120.7°-300.7°N（即WNW-ESE），标准偏差为9.2°，与映秀-北川断裂带的应力状态一致。 2008年汶川地震的主要断裂带之一。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号