Patent ID: 6721661
Filing Date: 2004-04-13
Classification: G01V

Abstract:
A method for distinguishing rock layers that were deposited while the rate of supply of sediment exceeded the rate of increase of accommodation space from rock layers that were deposited while the rate of increase of accommodation space exceeded the rate of supply of sediment, said method comprising the steps of:(a) selecting a first physical property of rock and a second physical property of rock from those sedimentary rock properties expected to show a variation arising from cyclic geological processes; (b) obtaining measurements of said first physical property as a function of depth; (c) obtaining measurements of said second physical property as a function of depth; (d) manipulating said measurements of said second physical property to obtain an estimate of rock layer thickness as a function of depth; (e) determining a slope of said first physical property as a function of depth and a slope of said estimate as a function of depth; (f) identifying first-type zones and second-type zones, wherein for said first-type zones said slope of said first physical property is equal in sign to said slope of said estimate and wherein for said second-type zones said slope of said first physical property is opposite in sign from said slope of said estimate; (g) using said first-type zones and said second-type zones to distinguish between (1) periods during which said rate of supply of sediment exceeded said rate of increase of accommodation space and (2) periods during which said rate of increase of accommodation space exceeded said rate of supply of sediment.