• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Pure and Applied Geophysics >3-D Modelling of Campi Flegrei Ground Deformations: Role of Caldera Boundary Discontinuities
【24h】

3-D Modelling of Campi Flegrei Ground Deformations: Role of Caldera Boundary Discontinuities

机译：Campi Flegrei地面变形的3D建模：破火山口边界不连续性的作用

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

Campi Flegrei is a caldera complex located west of Naples, Italy. The last eruption occurred in 1538, although the volcano has produced unrest episodes since then, involving rapid and large ground movements (up to 2 m vertical in two years), accompanied by intense seismic activity. Surface ground displacements detected by various techniques (mainly InSAR and levelling) for the 1970 to 1996 period can be modelled by a shallow point source in an elastic half-space, however the source depth is not compatible with seismic and drill hole observations, which suggest a magma chamber just below 4 km depth. This apparent paradox has been explained by the presence of boundary fractures marking the caldera collapse. We present here the first full 3-D modelling for the unrest of 1982–1985 including the effect of caldera bordering fractures and the topography. To model the presence of topography and of the complex caldera rim discontinuities, we used a mixed boundary elements method. The a priori caldera geometry is determined initially from gravimetric modelling results and refined by inversion. The presence of the caldera discontinuities allows a fit to the 1982–1985 levelling data as good as, or better than, in the continuous half-space case, with quite a different source depth which fits the actual magma chamber position as seen from seismic waves. These results show the importance of volcanic structures, and mainly of caldera collapses, in ground deformation episodes.
机译：Campi Flegrei是位于意大利那不勒斯以西的破火山口综合体。上一次喷发发生在1538年，尽管此后火山爆发了动乱，涉及快速而大的地面运动（两年内垂直方向高达2 m），并伴有强烈的地震活动。可以通过弹性半空间中的浅点源对1970年至1996年期间通过各种技术（主要是InSAR和水准仪）检测到的地表位移进行建模，但是该源深度与地震和钻孔观测值不兼容，这表明深度不到4公里的岩浆房。这种明显的悖论是由标记破火山口塌陷的边界裂缝的存在来解释的。我们在这里展示了1982-1985年动乱的第一个完整3D模型，包括破火山口边缘骨折和地形的影响。为了模拟地形和复杂火山口边缘不连续性的存在，我们使用了混合边界元法。先验破火山口的几何形状最初是通过重量建模结果确定的，并通过反演进行精修。破火山口的不连续性使得其与1982-1985年水平数据的拟合效果好于或优于连续半空间情况，其震源深度相差甚远，与地震波所见的岩浆室实际位置相符。 。这些结果表明，在地面变形事件中，火山构造（主要是火山口倒塌）的重要性。

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