The impact of diagenesis on the spatial and temporal distribution of reservoir quality
in C and D Members of the Arab Formation (Jurassic), UAE

Drs Sadoon Morad and Ihsan Al-Aasm

Summary

 
     

 
Generalized stratigraphic column of the Late Jurassic to Early Cretaceous successions.

Like other carbonate successions, the reservoirs quality and heterogeneity of the Arab Formation, which has been deposited in evaporative ramp setting, are inherently challenging to secondary and tertiary recovery, owing to commonly complex depositional environment, diagenesis, and structural evolution.

The objective of this research project is to elucidate and predict the impact of diagenetic alterations on the spatial and temporal distribution of reservoir quality and heterogeneity in the C and D Members of the Arab Formation in Abu Dhabi Field. This goal can be better achieved and the predictive conceptual models can be developed when the impact of these diagenetic alterations on porosity-permeability is linked to: (i) structural setting, e.g. in the crest versus flanks of the anticline and role of fractures as conduits for fluid flow, (ii) depositional facies, and (iii) sequence stratigraphic framework (systems tracts and key sequence stratigraphic surfaces) of the carbonate successions. The study will be conducted employing an integrated analytical approach, which involves micro- and macro-structural analysis of deformed carbonate rocks, petrophysical data, as well as petrographic, micro-thermometric (fluid inclusions) and geochemical (major, trace, REE as well as stable and radiogenic isotopes) analyses of the diagenetic minerals and of host carbonate rocks.


     
8854 isopachous calcite 10772
10780 10715
10564 8878 vug filled with anhydrite and gypsum (or silica)

Optical photomicrographs showing various diagenetic alterations in the Arab Formation.