ABSTRACT: High resolution sequence stratigraphy of the Minas Oil Field : a key reference for reservoir management and EOR field development
Toha, Budianto , Gadjah Mada University, Yogyakarta, Indonesia
High resolution sequence stratigraphy of the Minas Oil Field is now being incorporated in the subsurface work process. Cores and well-logs data from particular area of the field are utilized as a model to illustrate its application for reservoir management and EOR field development.
The depositional environment from the D up to A1 sand reservoirs range from braided fluvial systems, braid delta plain, mouth bars, and prodelta - shelf mudstones, which overall suggests a braid delta depositional system. Those facies successions indicate a large scale regressive - transgressive cycle, punctuated by several smaller-scale sequences. Each higher-order sequence exhibits a similar internal pattern, with amalgamated basal lowstand of braided fluvial or distributary channel coarse to conglomeratic sand, overlain by transgressive bioturbated sands ("estuarine" facies), and capped by prograding bioturbated mouth bar sandstones. Changes in grain size and bedding pattern within each facies tract create significant internal contrasts in porosity and permeability; therefore, three different flow units is determined, i.e. lower (K < 104mD) , intermediate (K a 103mD-102mD at the top), and upper (K < 103mD).
The sand-facies maps will exhibit paleogeographic trends that can be utilized to optimize recovery from these units. These maps and its stratigraphic subdivisions will be very useful for reservoir and production engineers in future targeting of specific recovery initiatives.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia