GEOHISTORY, THERMAL HISTORY AND HYDROCARBON GENERATION HISTORY OF NAVARIN BASIN COST NO. 1 WELL, BERING SEA, ALASKA

Abstract

Using a one‐dimensional model, we numerically simulate with time the geological processes of sedimentary deposition, compaction, fluid flow, heat flow and hydrocarbon generation. Input well data, in the form of present‐day formation thicknesses, porosity with depth, thermal gradient, vitrinite reflectance with depth, and fluid overpressure with depth constrain the dynamical model. We present model results for the Navarin Basin COST No. 1 well, including reconstructions of burial history, fluid flow history, thermal history and hydrocarbon generation history.We also demonstrate how important geophysical variables (such as permeability, porosity, fluid pressure, fluid‐flow rate, and thermal maturity indicators) vary with depth and time. Comparison of the model results with observed data illustrates and emphasizes the capabilities of the modelling procedure.The significance of the dynamical model is that it permits a quantitative assessment to be made of (i) the timing and depth locations of the generation and migration of hydrocarbon in a basin, relative to the formation of structural and stratigraphic traps: (ii) the timing of the production of overpressuring and fracturing within a basin: and (iii) the effect of cementation and dissolution on the retention of hydrocarbons in a trap. The model also enables an assessment to be made of the most likely prospective areas for hydrocarbon accumulation in a basin.