METHOD FOR DETECTING HIGH-RATE OBJECTS OF BRINE- AND GAS-BEARING STRUCTURES WITH ABNORMALLY HIGH FORMATION PRESSURE OF FLUIDS FOUNTAIN-HAZARDOUS FOR DRILLING WELLS Russian patent published in 2018 - IPC G01V1/00 G01V1/40 G01V9/00 

FIELD: geology.

SUBSTANCE: invention relates to the field of geology, namely the prediction of the distribution of water-bearing structures with anomalously high fluid pressure (AHRP) in a geological section of a sedimentary cover of platforms and the areas of their juncture with fore deeps. Invention includes field geophysical studies (seismic investigations – the method of determining the depth point (CDP)), well drilling, carrying out geophysical studies in an open hole, vertical seismic profiling (VSP). According to the seismic data of the MOGT in the halogen-carbonate stratum of the sedimentary cover, a region of nappe-imbricated overthrusts is identified with mapping of a frontal part of a detached thrust plate bounded by an allochthonous linear anticline along a front. Internal structure of the packet of detached and displaced plates of the allochthon in a supernumerary wing is clarified. In this case, the entire thickness of the carbonate interlayers of the zone of detachment influence in a line of an overthrust plate of the allochthonous anticline with the zone of development of secondary fracture reservoirs in fracture carbonate inter-salt layers is identified with a potentially dangerous zone of possible brine occurence with the AHRP of the saturating fluid system (brine, gas). Then, according to the set of geophysical well logging (GWL) and VSP data, zones of the anisotropy of the acoustic properties, interpreting them as the areas of development of the anomalous-hydro-conductive reservoir of the vein type are revealed, which are identified with the zones of localization of high-rate objects that are fountain-hazardous for drilling wells in inter-salt carbonate strata.

EFFECT: increase in the technological reliability of oil and gas deposits development.

1 cl, 2 dwg