Present Thermal Conditions in Baltimore Canyon and Georges Bank Basins in Relation to Extensional Models: ABSTRACT

Abstract

We examine the thermal evolution of the Baltimore Canyon and Georges Bank basins to derive their present temperature structure. Our models are based on the hypothesis that these basins have formed over continental crust which was thinned by extension during the opening of the Atlantic Ocean. The cooling and subsidence history are simulated using two-dimensional finite difference techniques. The results of this work demonstrate that the extensional model is consistent with seismic, gravity, and heat-flow observations in the two basins. Since the model reliably predicts the observed features of the basins, we believe that its predictions for the temperature structure of the basins are also reliable. The thermal gradient, heat flow, and temperature at depth in the two basins are expected to vary laterally because of variations in the amount of crustal thinning, sediment distribution, and basement depth. The Baltimore Canyon basin is characterized by one large sediment depocenter, while the Georges Bank basin has several smaller depocenters. This difference is character may be attributed to the oblique, rather than normal, orientation of rifting in the Georges Bank area. The modeling technique used predicts what effects these types of features will have on the present temperatures and temperature history of these parts of the continental margin. End_of_Article - Last_Page 1363------------