Testing of a permanent orbital surface source and distributed acoustic sensing for monitoring of unconventional reservoirs: Preliminary results from the Eagle Ford Shale

• DOI: 10.1190/geo2020-0403.1
• Publication Date: 2020-12-14T01:26:42Z
• Authors: Feng Cheng; Julia Correa; Shan Dou; Barry Freifeld; Todd Wood; Kurt Nihei; Dante Guerra; Jens Birkholzer; Benxin Chi; Jonathan Ajo-Fran...
• Keywords: Seismic vibrator; Microseism; Repeatability; Geophone; Petrophysics

The effective monitoring of hydraulic fracturing in unconventional oil and gas production requires tools to quantify elastic property variations even the absence microseismic activity. To track subtle time-lapse reservoir properties during such activities, techniques with high repeatability resolution, spatially temporally, are required. Distributed acoustic sensing (DAS) is a rapidly maturing fiber-optic technology for low-cost, permanent, density, in-well monitoring. Surface orbital vibrators (SOVs) inexpensive fixed rotary seismic sources that offer opportunity frequently interrogate subsurface energies comparable vibroseis sources. We have evaluated field vertical profile test, conducted Eagle Ford play, pairing an SOV source recorded by DAS behind casing deviated well better evaluate potential set determine data processing workflow using SOV-DAS system. analyze characteristics system, including signal-to-noise ratio repeatability. High-quality P- S-wave reflections, as mode conversions, visible section. In addition, clear P-P reflections also observable along horizontal sections. Time shifts mean value 10 μs between different sets demonstrate semipermanent source, which crucial analysis. apply reflection imaging on P S reveal depths. first-of-its-kind deployment, we implemented rotating slewing bearing discuss possibility optimize construction specific orientation directions. Our preliminary results indicate combination repeatable surface SOVs has significant providing low-cost approach high-resolution reservoirs.