Processing of Pseudo 3D VSP Acquired Using Permanent Fibre Optic Technology Deployed in an Exploration Well
M. Ferla, F. Miranda, A. Malossi, G. Nutricato, S. Moriggi, G. Galli, M.L. Khaitan and P. Bettinelli
Event name: 81st EAGE Conference and Exhibition 2019
Session: Borehole Seismic Methods I
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 601.82Kb )
Price: € 20
3D Vertical Seismic Profile (VSP) has long been viewed as conceptually attractive for illuminating targets under complex overburden, both for exploration purposes and for time-lapse monitoring of reservoirs. However, the widespread use of 3D VSP has been hindered by the cost and risk of deploying geophones in a borehole, by the limited availability of accessible wells and long operational acquisition time (Mateeva & al., 2014). These hurdles are largely removed when acquiring downhole seismic with a new measurement called heterodyne Distributed Vibration Sensing (hDVS) which is an innovative technology to improve the duration of borehole seismic operations. The hDVS technology uses optical fiber as a vibration sensor that can be used along the entire well depth as a sensor. We designed a pseudo 3D VSP survey (four Walkaway VSP lines and 2 circles) with the optical fiber clamped permanently to the well completion tubing. The main objective of acquiring the survey was to further investigate the Silurian and Ordovician formations by integrating VSP measurements with the available surface seismic surveys using the optical fibre measurements as well as to assess hDVS technology for Imaging. In this paper, we present the results achieved after processing the pseudo 3D VSP survey.