Quantitative prediction of multi-period tectonic fractures based on integrated geological-geophysical and geomechanics data in deep carbonate reservoirs of Halahatang oilfield in northern Tarim Basin

Abstract

Multi-period tectonic fractures are common in deep carbonate reservoirs. It's difficult to identify and has the characteristics of stochastic spatial distribution. The quantitative prediction of fractures is critical for unravelling their spatial distribution and for understanding tectonic evolution and stress field distribution. Focusing on the Halahatang oilfield in northern Tarim Basin, outcrop surveys, drilling cores, thin sections, well logs, and seismic data were comprehensively used to better determine the development characteristics, formation time, and spatial distribution of multi-period tectonic fractures based on finite element tectonic stress field simulation. The strike-slip fault system was characterised based on post-stack seismic structural interpretation. By simulating the tectonic stress field in three different tectonic movement periods, taking the fracture density as the evaluation parameter, the spatial distribution characteristics of multi-period fractures were quantified. The numerical simulation results indicated that the development of fractures is controlled by the strike-slip fault, and the Middle Caledonian period is the main formation period of these fractures. This method can accurately predict multi-period complex fractures and can also be applied to other deep carbonate reservoirs.