Crustal Imaging Through Geotomography and Wavefield Migration of Reflected Head Waves: Application to the Kentland Dome

在之前NSF的资助下，我们进行了一项新颖的实验，研究印第安纳州肯特兰附近一个似乎是化石陨石坑中央隆起区的内部结构。我们请求资金来分析这些数据，以完善我们对其结构的了解，使用三种工具。(1)使用常规方法对8英里的反向和分裂折射数据进行分析，以解决1.5×2英里矩形研究区域边缘周围的构造细节。(2)应用一种新技术，即扇形炮检地层析成像，可用于在折射层深处的穿过地球的二维切片上反演横向速度变化。(3)新的横向反射头波波场偏移成像技术的开发与应用。利用这项技术，我们希望沿着穿过地球的水平切片成像主要的横向不连续，分辨率可与地下分层的垂直入射反射数据图像相媲美。后两种技术需要一些额外的技术开发。随着进一步的发展，这些技术可能会被证明是有价值的应用于未来大规模的岩石圈结构调查。

Under previous NSF funding we conducted a novel experiment to study the internal structure of what appears to be the central uplift region of a fossil meteor crater near Kentland, Indiana. We request funds to analyze these data to refine our knowledge of their structure using three tools. (1) Analysis of 8 miles of reversed and split refraction data using conventional methods to resolve structural details around the edges of 1.5 by 2 mile rectangular study area. (2) Application of a new technique called fan shot geotomography that can be used to invert for lateral velocity variations on a two dimensional slice through the earth at the depth of the refracting layer. (3) Development and application of a new wavefield migration technique for imaging laterally reflected head waves. With this technique we hope to image major lateral discontinuties along a horizontal slice through the earth with a resolution comparable to normal incidence reflection data images of subsurface layering. The later two techniques require some additional technical development. With further development these techniques may prove valuable for application to future large scale investigations of lithospheric structure.