Fractures characterization of carbonate reservoir using core analyses and borehole image logs

In this research, we used a combination of available data (core analysis and borehole image logs) to characterize the Judea Formation sediment fractures. The Judea Formation low-energy marine shelf sediments are made up of limestone in the upper half and dolostone in the lower. Some induced and enhanced fractures with an N-S striking direction were identified using FMI image logs. Furthermore, the rock naturally fractures with an NNE striking orientation. The characterization of fractures using core studies revealed that the limestone zone had a greater quantity of induced fractures than the dolomite zone. Within the dolomite zone, naturally occurring fractures are frequent; they are open or partially filled with secondary mineralization. Due to the breaking of the limestone matrix under compression during burial diagenesis, sealed fractures with calcite are primarily recognized in the limestone zone. Due to the plastic deformation/pressure solution of the soft carbonate host rocks, sealed fractures with clay are most prevalent in the limestone zone. Because of their link with the dolomitization that floated over the lower part of the Judea Formation section during diagenesis, sealed fractures with dolomite were primarily identified in the dolomite zone. As a result of the significant dolomitization, sealed fractures containing bitumen formed within the dolomite zone conduits, serving as hydrocarbon migration pathways. The paragenetic sequence is given, although it is stressed that many parts are still hypothetical owing to the inadequate database. Geological and/or other projects in the Euphrates Graben area can use help from such an integrated study.

Automated summary

This research characterizes fractures in the Judea Formation using a combination of available data. The limestone zone has more induced fractures compared to the dolomite zone, while the dolomite zone has frequent naturally occurring fractures that are open or partially filled. The fractures in the limestone zone are primarily caused by fracture of the limestone matrix and plastic deformation of the soft carbonate host rocks, while the fractures in the dolomite zone are primarily associated with dolomitization processes.