Fault Compartmentalization of Stacked Sandstone Reservoirs in Growth-Faulted Subbasins: Oligocene Frio Formation, Red Fish Bay Area, South Texas
نویسندگان
چکیده
An integrated study using 3D seismic, wireline logs, and core analyses was conducted to establish strategies for exploring in compartmentalized, lowstand, prograding, deltaic systems. Frio sediments, averaging ~11,000 ft, are commercial gas reservoirs in several of the growth-faulted, intraslope subbasins in South Texas. These exploitation targets are typically located in faultbounded compartments that form threeand four-way structural closure. However, understanding the stratigraphic component is crucial to successful exploitation of these sandstones. The Frio third-order lowstand prograding wedge in Red Fish Bay Field is composed of 10 higher order, lowstand deltaic and superposed transgressive, depositional systems tracts. The sandstones are fine-grained, lithic arkoses having a mean porosity of 20% and tens of millidarcies of permeability. The main constituents of these sandstones are quartz, feldspar, and volcanicrock fragments. Feldspars typically exhibit a substantial amount of secondary dissolution and micropores. Quartz cements, as well as interstitial clays, are minor. Porosity reduction occurs primarily by compaction. Gravity failure along the upper slope generated syndepositional faults that displaced mobilized mud basinward of a growing lowstand sedimentary wedge. These growth faults trend generally northeast-southwest, setting up small subbasins. Associated with the growth faults are numerous subparallel, postdepositional synthetic faults. In addition, normal faults trend perpendicular to the growth faults, establishing a complex pattern of fault compartmentalization, which dissects the prograding-wedge depositional patterns. Pressure-decline analysis demonstrates compartmentalization that is due to (1) laterally discontinuous
منابع مشابه
Seismic Geomorphology of Oligocene Frio Lowstand Slope and Basin-Floor Sedimentary Bodies in Growth-Faulted Subbasins in South Texas
Architecture of slopeand basin-floor-fan systems in growth-faulted subbasins along the south Texas Gulf Coast developed as a result of interplay between synsedimentary tectonics and sedimentation during third-order sea-level lowstands. These subbasins, or intraslope basins, have not been adequately explored for their slope and basin-floor-fan potential, as have the intraslope basins in salt-dom...
متن کاملMineralogy, geochemistry and conditions of formation of The Band -e- GhichyCopper-Celestite deposit Torud area, South of Shahrood
Band-e-Ghichy copper deposit is located in the northern margin of the Central Iran structural zone, about 120 km south of Shahrood and 70 km south east of Torud. Copper mineralization occurred in the rock units including sandstone, conglomerate and siltstone with the Oligocene age. Mineralization has occurred in the form of stratiform (syngenetic), stratabound (epigenetic) and supergen (the sur...
متن کاملDetermination of geomechanical parameters of Sarvak formation using seismic, and well-log data in one of the hydrocarbon fields at the southwest of Iran
Nowadays geomechanics plays a major role in optimizing the production and development stages of hydrocarbon reservoirs. The high cost of drilling wells and maintaining a functional well entails companies to utilize geomechanical modeling to determine the most efficient drilling path and the safest mud windows in order to maintain the stability of the well and prevent critical fracturing and col...
متن کاملDetermination of a Conceptual Model for the Structural Features and Pb–Zn Mineralization in the North of Behabad Fault Zone, Central Iran
The Behabad region is located within a tectono–sedimentary zone in southeast Yazd province, Central Iran. The tectonic activities have deformed and faulted the Mesozoic and Quaternary formations in this area. The faults in Kuhbanan and Behabad have played a key role in the evolution of geological events, mineralization, and the formation of Behabad–Kuhbanan horst. These faults have separated th...
متن کاملSite-specific sequence-stratigraphic section benchmark charts are key to regional chronostratigraphic systems tract analysis in growth-faulted basins
Subbasins composing a larger basin can have similar appearing sediment fills that are diachronous. It is important to construct a chronostratigraphic section for each subbasin to correctly correlate between subbasins. A methodology is presented that incorporates the sequence-stratigraphic interpretation of each subbasin, which improves correlation of systems tracts between adjacent and widely s...
متن کامل