Characteristics of Recent Crustal Movements in Jiashi and Its Neighboring Regions on the Basis of Gravity and GPS Data
详细信息
- 责任者：Liu Daiqin (Earthquake Administration of Xinjiang Uygur Autonomous Region ; Urumqi 830011 ; China ) ; Li Jie
- 刊名：Earthquake Research in China
- 出版年：2011
- 卷期：27(2)
- 关键词：重力场 ; gravity field ; 地壳运动 ; crustal movement
- 页码：p.182-191
- 图表：illus., 26 refs.
- 分类号：0400
- issnNo：ISSN1001-4683
- isbnNo：CN11-2008/P
摘要
The paper studies the characteristics of crustal movement in Jiashi and its neighboring regions on the basis of gravity and GPS data.The adjustment calculation was done using the 2005~2009 gravity observation data flow and one-year gravity field variation scale images were drawn.The analysis reveals that the gravity field variations in the region is relatively active and follow certain patterns with the maximum cumulative gravity anomaly reaching 150×10-8 m·s-2.The paper then recalculates the GPS data of 2005~2009 in the region under a unified framework and obtains the annual surface expansion in the region by theoretical calculation.The result shows that the regional crustal surface compression and surface expansion have an alternating pattern,and the positive and negative junction is the increase area of shear strain,often the earthquake preparation area.Finally the paper discusses the correspondent relationship between gravity and GPS(surface expansion) in crustal deformation and geodynamics.The study shows that there are positive variations of gravity in Jiashi and its neighboring regions before a quake and negative ones in large areas after a quake.This can result from the alternation of indentation(surface contraction) and northward expansion(surface expansion) and is consistent with surface expansion by GPS calculation.