This deep circulation is causing a considerable part of the basin's elevated heat to be transported to the LYG outlets, preventing shallow thermal expression at the GH.
Some live in shallow thermal springs at temperatures slightly above 42 °C (100 °F), others in cold Arctic seas a few degrees below 0°C32(32 °F) or in cold deep waters more than 4,000 metres (13,100 feet) beneath the ocean surface.
Model results indicate that regional mean basal heat flow value of the GH is 100 mW/m2, and that the shallow thermal anomaly of the LYG is an expression of a deep crust geothermal anomaly.
We find that the shallow thermal field is strongly affected by basin-wide fluid flow.
Second, we estimate two-dimensional shallow thermal structures in the Nankai subduction margin that are constrained by temperatures at BSRs.
We also estimated heat flow from BSR depths, evaluated the error, and modeled the shallow thermal structure constrained by the temperature at BSR depths.
Regional effects affecting the deeper part of the system and local effects having the strongest influence on the shallow thermal field can be distinguished.
Even considering 3D heat transport such a topographic effect on the temperature distribution can be traced downwards to upper crustal levels, causing local short-wavelength temperature anomalies in the shallow thermal field.
In summary, the shallow thermal structure that considers the topographic effect is of use in estimating the subseafloor temperature and also for understanding past surface geological phenomena, such as active sedimentation or erosion.
In order to obtain the shallow thermal structure below the seafloor, we solved the following two-dimensional steady-state equation: frac{{partial^{2} T}}{{partial x^{2} }} + frac{{partial^{2} T}}{{partial z^{2} }} = 0, (1)where (T) is the subseafloor temperature, (x) is the horizontal coordinate, and (z) is the vertical coordinate.
The temperatures at the BSR depths were used for the boundary condition (b) to restrict the calculated thermal structure by choosing the best coherency between the temperature at the BSRs and the calculated temperature at the same depth of the shallow thermal structure.
