Reasons for shallow depth by t0 method in shallow seismic refraction wave method

摘要：

From an actual problem,that the interpretation depth of the seismic profile by to method based on camber time distance curve existing in the refract wave blind area is lean to shallow,we have analyzed its reasons as follows: ①The surface velocity is gradually increasing (velocity changing factor K ≠ 0 ),which is not a idea average velocity layer.In the refract wave blind area,inflect waves take place of direct waves and the term V1,which is obtained by the straight line between explosion spot and the fast point of inflection,is lean to small;②The value of t0 at close explosion spot to is lean to small.Additionally,we have proved that direct waves are same as inflect waves and the time distance curve can be regarded as beeline in the refract wave blind area,under a theoretical condition with K→0.Finally,we figured out the correct method to revise the term V1 and analyzed reasons of t0 close to shallow.Several engineering applications showed our method is correct and effective.

关键词： shallow layer quake t0 method depth shallow inflect wave direct wave point of inflection value V1 revision means

作者: Qi Wu Jingtian Tang Ling Li

作者单位: School of Info-physics & Geomatics Engineering,Central South University,Changsha,Hunan 410083,China School of Info-physics & Geomatics Engineering,Central South University,Changsha,Hunan 410083,China China university of geosciences,Wuhan 430074,China

会议类型: 国际会议

会议名称: The 3rd International Conference on Environmental and Engineering Geophysics(第三届环境与工程地球物理国际会议)

会议地点: 武汉

会议语种:英文

页码: 223-226

在线出版日期: 2008-06-15（万方平台首次上网日期，不代表论文的发表时间）