Estimating hydraulic conductivity for the Martian subsurface based on drainage patterns — A case study in the Mare Tyrrhenum Quadrangle

Hydraulic conductivity K, as the coefficient of proportionality in Darcyʹs Law, is critical in understanding the past Martian hydrologic cycle, climate, and landform evolution. However, K and its spatial variability on Mars are thus far poorly constrained due to lack of accessibility. Using an innovative method based on surface drainage dissection patterns, which has been successfully tested in the Oregon Cascades on Earth, we estimated K in the Mare Tyrrhenum Quadrangle on Mars. The basic assumption is that under long-term dynamic equilibrium conditions, the overall dissection pattern in a watershed as reflected in drainage density is controlled by the interplay among surface runoff, groundwater flow, topography, and aquifer properties. K is calculated following a derivative of Darcyʹs Law under DuPuit–Forchheimer assumptions with drainage density D, valley depth d, recharge rate R, and aquifer thickness H as inputs. The results are consistent with the published K values and reveal spatial variability.