Год издания: 2020

Hydraulic fracture geometry characterisation is often addressed with downhole seismic observations, this technology is widely applied and named as downhole microseismic monitoring. This type of monitoring involves installation of 3C seismic receivers into the neighbouring to the monitored process well sometimes two or more monitoring wells are used for the receivers installation. One of the key requirements for further processing, in this case, is the exact timing between the records of different monitoring wells. Usually, this task is solved at the hardware level and, in case of ideal observations, timing correction procedures are not required. In some cases, hardware timing between wells is knocked down and for the correct use of observed data, the offset in timing needs to be compensated. In this paper, to retrieve timing knockout we introduce into the inversion the additional set of the parameters responsible for the asynchronous records of microseismic events: unknown time shifts into the observed arrival times of one of the monitoring wells. We show here that for simple isotropic media and great acquisition system this timing knockouts seem to be retrieved precisely but for the more complex media (anisotropic VTI) the determination may be questionable.