Hierarchical Facies Modeling Driven by Core: A Case Study from Samarang

A novel approach focused on core driven hierarchical facies association for static modeling has been pioneered in the Samarang field, offshore Sabah. The field is located in a structurally complex area representing paleo shoreface environment. The structure as interpreted from the Seismic represents a crestal collapse area. The area of interest is Late Miocene shallow marine section showing repeated progradation and retrogradation within a major regressive clastic wedge that was building towards the NW. Individual Samarang reservoirs were interpreted to portray wave/storm dominated sand bodies forming in upper to middle to lower shoreface and offshore transitional environments, accumulating in a coastal to inner shelf. The upper to middle shoreface sandstones typically were good reservoir quality - massive to laminated sands, whereas the lower shoreface to offshore transitional environment was characterized by poor-quality, bioturbated to heterolithic sands that were formed as event beds during storms. The shales were typically formed in the offshore inner neritic shelfal environment.The methodology described above, provides a robust integration in facies modeling workflow whereby core-driven facies association in a shoreface environment have been captured, characterized, and represented in static and dynamic models.