DAS-VSP Enhanced Processing of Simultaneous Acquired Surface Seismic Data

Abstract

Summary Distribute Acoustic Sensor (DAS) is increasingly recognized as a viable alternative to geophone arrays for the acquisition of borehole seismic. The ability to deploy optical fibers into a well, either as a cable based intervention or as part of a completion string, allows for the entire wellbore to be surveyed with every source activation. This can dramatically reduce the operating time required to complete a normal survey as well as offering the opportunity to achieve much higher spatial coverage than is typical of current technologies. The ability to acquire borehole seismic data in a producing well without the need to disrupt production also offers significant benefits to the operator. In order to obtain the characteristics of shallow shale gas reservoir in Southwest China and to overcome the difficulties of low coverage and difficult imaging of shallow target layers with 3D surface seismic data, a simultaneous acquisition project of 3D surface seismic and 3D VSP data was implemented in Zhejiang Oilfield, and DAS technique was used in 3D VSP data acquisition. This paper takes Zhejiang Oilfield 3D DAS-VSP project as an example to introduce data quality of DAS acquisition, and signal to noise ratio (SNR) improvement technique in DAS-VSP data processing.