Studying the geoid and viscosity structure in a thermochemical model based on seismic tomographic data

  • 邓春林
  • 创建于 2018-07-20

报告题目:Studying the geoid and viscosity structure in a thermochemical model based on seismic tomographic data

报告时间:2018年7月23日15:00-17:00

报告人:刘 曦 博士后

        加州理工学院

报告地点:中国科学院计算地球动力学重点实验室会议室
               中国科学院大学科研楼106室
 
报告摘要:
 

The geoid, one of the most important geophysical observations, has been well explained in mantle flow models with the buoyancy inferred from seismic models that in turn place constraints on mantle viscosity structure. These models often assume a simple whole-mantle convection with uniform composition and 1-D viscosity. However, seismic and geochemical observations suggest possible existence of chemically distinct piles under Africa and Pacific which extends hundreds of kilometers above the CMB (i.e., LLSVPs).  We formulate a thermochemical mantle model with chemically distinct and stable piles. This models can reconcile the geoid observation with the interpolation of LLSVPs as long-term stable chemical piles. The viscosity structure as well as density anomalies in the thermochemical mantle are inferred.