Distributed acoustic seismic systems in VSP acquisitions

Distributed acoustic sensing (DAS) has wide acceptance in well’s seismic prospecting since 2012. Practice work shows that these systems are effective. The records have positive quality and they allow you to simultaneously receive and record vibrations along the entire length of fiber-optic cable, which eliminates the need to navigate through the borehole of single or strings of geophones, minimize quantity of required affectings and them not sensitive to external electric and magnetic fields. These featuresof fiber-optic systems determine considerable prospects for their application.Application of fiber-optic systems are still experimental and methodological in nature and focused on the development and optimization of technologies of exploration and evaluation capabilities of new systems in the whole complex of borehole research.
Materials and methods
The article presents the results of application in borehole seismic fiber-optic distributed systems based on foreign publications.
Results
The review of publications about application the of fiber-optic systems in vertical seismic profiling revealed:
• seismic materials with new and conventional receivers have identical quality;
• methods for determining the depth of immersion cable are considered;
• the using of fiber-optic systems is possible and effective in one-dimensional and three-dimensional shooting VSP in operationaland injection wells;
• summing of multifrequent increases the signal to noise ratio and the quality of materials.
Сonclusions
The application of fiber-optic distributed receiving system provides opportunity to significantly simplify the borehole seismic works and cut their costs without reducing the quality of the materials. The introduction ofthis technology into production will expand the volume of borehole seismic and increase its effectiveness.