Permeability of Unconsolidated and Consolidated Marine Sediments, Gulf of Mexico

ABSTRACT Permeability of a large number of natural marine sediment samples from the Gulf of Mexico was determined through the use of laboratory consolidation tests. The samples were divided into the following groups: Group 1, sediment consisting of more than 80% clay (material 2µ or less in size); Group 2, sediment containing from 60 to 80% clay size material; Group 3, silty clays with less than 60% clay; Group 4, silts and clays that have a significant sand size fraction present (more than 5% sand). The permeabilities of the groups ranged from 10-5 to 10-10 cm/sec with 35 normal seawater being used as the saturating fluid. A statistical analysis of the natural log of permeability versus porosity was used to develop the permeability prediction equation for each of the groups listed. The equation for Group I is k=eP(15.05)-27.37, for Group 2 k=eP(14.18)-26.50, for Group 3 k=eP(15.59)-26.65, for Group 4 k=eP(17.51)-26.93 and for all data k=eP(14.30)-26.30; where P is the porosity (in decimal) and k is the coefficient of permeability. These equations are useful for predicting changes in permeability with depth in fine grained sediments of the Gulf of Mexico. The ability to predict permeability in a continuous sequence, where the deposition history is known, may explain the large variations that we see in the physical properties in sediments similar in grain size and mineralogy. End_of_Record - Last_Page 350-------