No abstract

A field solution for long wavelengths of the equation of heat conduction is obtained for a composite material with orthorhombic symmetry. This yields exact expressions for the three principal thermal conductivities. They are valid for any number of ortho rhombic constituents and even for continuously varying thermal conductivities within the elementary cell. For a lamellar composite, the average thermal conductivities of the material are expressed directly as integrals over the space-dependent thermal conductivi ties. For a filamentary composite, such explicit expressions are obtained only in the Wigner-Seitz approximation and only for a stepwise variation of the thermal conductivities within the ele mentary cell. In the same manner, the average thermal conduc tivity of a composite with cubic symmetry, e.g. isotropic spherical inclusions in a cubic lattice, is calculated. Analogies with previous results on diffusion coefficients and elastic shear moduli are discussed.

No abstract

We made 74 closely spaced (< 2 km apart) heat flow measurements around and over two salt structures on the Texas continental slope, Gulf of Mexico. The values outlined the shape of the heat flow anomalies over both structures. Based on a preceding high resolution seismic survey, we interpreted these structures to be a cylindrical plug and a salt tongue extending from the crest of a wall‐shaped feeder. The heat flow observations clearly reflect differences between the two features and are consistent with the prior structural interpretation. The values over the salt plug are nearly all greater than 70 mW/m². The measurements over the salt tongue have a sharp heat flow peak of 90 mW/m² associated with the presumed feeder and rather uniform values around 60 mW/m² over the remainder. The variation of heat flow over both structures is smooth and shows no apparent scatter. Heat flow values off these features are uniformly low, around 30 mW/m². Thermal effects from bottom water temperature fluctuation, slope sedimentation, diapiric movement of the salt body, and pore fluid migration appear unable to provide a satisfactory explanation for the observations. However, thickness variations of a highly conductive salt body can easily account for the heat flow anomalies. We suggest that modeling of the conductive anomaly should provide substantial constraints on the bottom geometry of the salt.