By Agu, Chinedu Providence
Well log shapes, cores and side wall samples used for environmental interpretation and
determination of lateral continuity, direction of seal, reservoir and source rocks do not
give reliable depositional model. The essence of this study is to use sequence
stratigraphic approach which involves interpretation and integration of wireline logs and
high resolution biostratigraphy and paleoecology from wells AG-0 I , AG-02, AG-03 and
AG-04 of X-field in Niger Delta to establish the depositional facies sequence
stratigraphic framework and synthesize a depositional model for the field.
The study area consists of six depositional sequence accumulated from Oligocene
to Miocene time. The depositioilal environment of the sequence is an estuarine valley.
Each sequence consists of :
(i) a basal conglomerate unit that reflects a fluvial system that progressively
became influenced by marine processes.
(ii) a medial sandstone and mud rock unit that represents deposition in the central
part of an estuary and
(iii) a cross stratified sandstone unit to the top, which represents the progradational
filling of.the bay-head of the estuary. Sequence stratigraphic analysis reveals
that the succession consists of six complete third order sequence, the complete