Characterization of the 3-D Properties of the Fine-Grained Turbidite 8 Sand Reservoir, Green Canyon 18, Gulf of Mexico
Core data showed that the main facies resulting from fine-grained turbidity currents is composed of alternating sand and shale layers, whose extension is assumed to be large. They correspond to levee and overbank deposits that are usually associated to channel systems. The high porosity values, coming from unconsolidated sediment, were associated to high horizontal permeability but generally low kv/kh ratio.
The location of channel deposits was not obvious but thickness maps suggested that two main systems, with a northwest-southeast direction, contributed to the 8 Sand formation deposition. These two systems were not active at the same time and one of them was probably eroded by overlying formations. Spatial relationships between them remained unclear. Shingled stacking of the channel deposits resulted from lateral migration of narrow, meandering leveed channels in the mid part of the turbidite system. Then salt tectonics tilted turbidite deposits and led to the actual structure of the reservoir. The sedimentary analysis allowed the discrimination of three facies A, B and E, with given porosity and permeability values, that corresponded to channel, levee and overbank deposits. They were used to populate the reservoir model. Well correlation helped figure out the extension of these facies.
Advisor:Ahr, Wayne M.; McVay, Duane A.; Watkins, Joel S.
School:Texas A&M University
School Location:USA - Texas
Source Type:Master's Thesis
Keywords:modelling levee laminated turbidite green canyon low resistivity sands
Date of Publication:05/01/2003