Geomorphology is the study of landforms and the processes that create them. Studying geomorphology enables an understanding of the Earth’s surficial processes, geology, and history, as well as that of other planets. Notably, there are many locations on Earth and other planets in our solar system with abundant elevation data available that can be used to define geomorphology, but without any coincident subsurface geologic data. The ability to predict subsurface geology features from these existing elevation datasets has the potential to expand our understanding of geologic processes, phenomena, and hazards.

The focus of this project is on determining whether the location of morphological features derived from bathymetric elevation data spatially correlates with the location of subsurface geologic features, such as faults, on the Cascadia margin region. Since geomorphology is challenging to classify quantitatively, classification schemas such as geomorphologic phonotypes and the bathymetric position index (BPI) were applied to seafloor bathymetry data to quantify and categorize the geomorphology of the study area. These classification results, together with other geomorphological variables (slope, aspect, rugosity, curvature), are used together to predict the location of faults. The model also evaluates whether the locations of seafloor seeps, pockmarks, and mud volcanoes contribute to the prediction of fault locations. Maximum entropy (MaxEnt) presence-only spatial distribution modeling is used to generate and validate a predictive model describing the relationship between seafloor morphology and subsurface geologic features on the Cascadia margin.

The resulting model is then applied to Martian geology, specifically a fault zone on Mars (Valles Marineris), a potential subduction system found on Mars’ Tharsis Plateau, and the long-hypothesized home of an ancient ocean, southern Utopia Planitia. Mars’ geomorphology is well characterized, but its subsurface structures are not as well mapped or understood as they are on Earth. By classifying and investigating possible correlations between surface morphology and subsurface geology (faulting) based on Earth analogue observations, this research has the potential to yield insight into the geology of Mars and demonstrate a transferable tool for geologic investigation of other planetary bodies.