Sequence stratigraphy has advanced considerably since the early
applications of the concepts on seismic data. It attempts to discern the
migration of facies re- sulting from changes in a combination of factors
such as, sea level, tectonics, climate and sediment flux, and integrates
it with a meaningful chronostratigraphy. The stratigraphic record is
envisioned as a framework of repetitive packages of genetically-related
strata, formed in response to the shifting base level, in which the
locus of deposition of various sediment types may be anticipated. This
attribute is rapidly promoting sequence stratigraphy as an indispensable
tool for prediction of facies in exploration and production geology. In
hydrocarbon exploration the application of sequence stratigraphy has
ranged from anticipating reservoir- and source-rock distribution to
predicting carbonate diagenesis, porosity and permeability. The
capability to anticipate vertical and lateral distribution of facies and
reservoir sands in the basinal, shoreface, incised valley-fill and
regressive settings alone has been a great asset for exploration. In
frontier areas, where data are often limited to seismic lines,
sequence-stratigraphic methodology has helped determine the timing and
of types of unconformities and anticipate transgressive- and
regressive-prone intervals. In production it is aiding in field
development by providing improved source and seal predictions for
secondary oil recovery. A recognition of stratigraphic causes of poor
recovery through improved understanding of internal stratal architecture
can lead to new well recompletions and enhanced exploitation in existing
fields. The sequence-stratigraphic discipline is in a state of rapid
expansion.
