Abstract: Geological Characterization and Modeling of Middle East Carbonate Reservoirs Through Multidisciplinary Integration, Advanced Technology and New Techniques

NURMI, ROY

Geological reservoir analyses continue to improve with advances in technology, integration, multidisciplinary efforts and geostatistical insights. Particularly important are new reservoir insights coming from the integration of geological data, well logs, and well testing from horizontal well data. Geologically guided pressure sampling and pressure-transient testing is quantifying the connectivity and production potential of a variety of heterogeneous pore systems and, thus, helping to define by-passed oil and also the multiple origins of early water production. Leached subaerially exposed surface and biostromal zones often act as conduits for lateral water flow, whereas open faults allow water flow both vertically and along their strike. Such high permeability zones can be used to enhance production if they do not extend to the oil/water or gas/oil contacts.

Careful integration of multidisciplinary data is critical to bringing together measurements and data of different disciplines, especially with variety of scales(SEM to seismic) and technologies. Pores and heterogeneities too large to be defined by core and/or borehole imagery alone are present in Arab and Mishrif biostromes and Tertiary coral/algal reef facies are best defined by integration of geoscience and logging data with fluid and/or pressure data. Although microporosity is generally examined in very small samples with a SEM, the continuous vertical distribution of microporosity and its variation around the wellbore is being mapped by integrating high resolution NMR well logging measurements and electrical borehole imagery. These recent investigations show micropores even can be important in the evaluation of high permeability Jurassic grainstones in addition to the well known pervasive microporosity in Tertiary reservoirs of Egypt and India and also Cretaceous(Thamama) reservoir zones of Arabia.

AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria