Physicists over the past century have postulated that the universal constant of gravitation, G, is decreasing with time. Assuming an annual rate of decrease of 10^-10 parts per year the gravitational acceleration of the earth, g, would have been 22% greater two billion years ago. Distal turbidites occur in geologic deposits as old as 2.5 billion years. Utilizing the relations developed by Scheidegger and Potter, a functional relation between g and measurable characteristics of a graded bed may be constructed. This relation, a "paleogravimeter," was tested in terms of sensitivity to changes in g as well as possible confounding effects such as sediment concentration, density, and grain packing. Only the sediment concentration in the turbidity current had a measura le effect. By utilizing Middleton's result that the transition between "distribution" grading and "coarsetail" grading occurs at particle concentrations of 30%, a selection criteria can be established for the "paleogravimetric camera." In this respect it is meaningful to measure only beds deposited from currents of the same particle concentration. When this is done the paleogravimetric change can be measured. The paleogravimetric camera can be improved by substituting more realistic relations for Stokes' Law and allowing viscosity to vary as suggested by Roscoe. Preferably however, a purely physical model for sedimentation from a turbidite should be developed in place of the Scheidegger-Potter relation.

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