Waveform Inversion-Assisted Distributed Reverse Time Migration for Microseismic Location

摘要

We present a novel approach to locate microseismic sources in situ and in real time in distributed sensor networks (DSN). We propose a distributed reverse time migration (RTM) microseismic source location algorithm. RTM-based methods have advantages in passive source location in terms of robustness and accuracy. However, the traditional methods have a centralized data collection and ex situ postprocessing style, and were not designed for in situ and real-time seismic imaging, so communication and computation costs were not considered. Utilizing newly emerging DSN, real-time and in situ microseismic source location becomes possible. Thus, we specially design a joint imaging condition for the DSN system to reduce both computation and communication burdens. The tradeoff, however, is location resolution reduction. Sequentially, we employ a waveform inversion approach to obtain a finer resolution microseismic source location result. Finally, we validate the proposed method using both synthetic and field seismic records. Our approach shows promising performances using synthetics with single and multiple sources, as well as with field data. The proposed waveform inversion-assisted distributed RTM location algorithm obtains high-resolution source location results and significantly reduced communication and computation costs, even at a low signal-to-noise ratio.