The technology for the study of structural peculiarities in the near-well space by Broadside VSP and PM Broadside VSP method
To evaluate geometry of reflecting boundaries, to detect and map tectonic faults and corresponding structural elements (uplifts, depressions), to detect zones with wedging of horizons and entrenchements, to evaluate lithological peculiarities in productive sediments.
Survey is conducted by a non-polarized modification of Broadside VSP (PM VSP). The survey radius is ½ depth of the target horizon bedding.
The basic technological activities when conducting borehole operations:
• survey is conducted in cased as well as in open holes;
• works are carried out from several vibration points moved away from the wellbore at the distance commensurable with the depth of the target reflecting horizons;
• elastic oscillations are recorded by a multi-component sonde along the wellbore with a 10-20м sample rate.
Application of the technology allows to:
• study the wave pattern formed by the boundaries of sedimentary cover;
• study the structural plan of the target reflecting horizon in the ½ radius of the target reflecting horizon bedding;
• detect tectonic faults and the zones of entrenchment development;
• forecast zones of reservoir argillization.
Advantages of the technology:
• an opportunity to conduct survey promptly allowing an operative support of the drilling process during prospecting and exploration in order to adjust well positioning points;
• multi-component recording allows to carry out processing for various types of waves;
• availability of the up-to-date software.
Broadside VSP time section,
tectonic faults detected
Structural map compiled according to
and Broadside VSP data