Fluvial Deposits and Reservoirs

摘要: Abstract There are different types of fluvial deposits and reservoirs. The two end-member depositional braided-river fluvial-river deposits. A third type, incised valley fill, can contain either or both these end members within the confines valley. In addition, near mouths valleys may become reworked by estuarine tidal processes, which ultimately produce a set reservoir properties. geometry, size, characteristics each type depend upon transportational, depositional, postdepositional (diagenetic) processes that controlled several external variables, including geographic location, sediment source areas (provenance), climate, degree tectonic activity. Braided-river tend to be relatively coarse-grained consist gravel sand, with little no mud. Because this, beds laterally continuous over much all width braidplain, although presence some shale disrupt continuity locally. By contrast, meandering-river finer-grained, more lenticular, partially completely encased in floodplain shales. Depending deposit's compaction cementation, its porosity permeability quite variable. However, general, facies porous permeable than facies. typical sequence stratigraphic stacking pattern for consists basal erosion surface, formed during falling stage relative sea level, sits, from base upward, lower deposit (deposited early turnaround level), floodplain–meandering-river system, then lacustrine and/or estuarine/floodplain transgressive systems tract, capped highstand floodplain/meandering-river As result differences properties, reservoirs expected have varied performances. Any reservoir-management plan should include an evaluation characteristics. For example, waterflood sweep efficiency will higher reservoir. Also, horizontal wells efficient discontinuous sandstones interconnected Seismic-reflection techniques, as well well-log, core, well-test analyses, used adequately define predict recovery performance