Planetary surfaces record an abundance of information on lithospheric evolution. Low rates of erosion allow for long-term preservation of structures, and on airless planetary bodies this can be billions of years. One such body is the Moon, which displays a long record of planetary tectonics on its surface. Brittle deformation in the form of fracturing provides vital clues for the characterization of the tectonics of the body, including localization, distribution, and kinematics of deformation in the lithosphere, lithospheric strength properties, and the underlying tectonic processes that are responsible for the observed deformation. Analyzing brittle deformation structures has direct implications for understanding planetary evolution, and this dissertation specifically addresses the extensional tectonics that cause complex fracture system formation and interactions with magmatism and volcanism, such as dike emplacement. Similarly, on Earth, brittle structures reveal the inner processes of our planet and analogue field studies on Earth are crucial to interpret geologic processes on extraterrestrial worlds.

Research presented in this dissertation uses fractures on planetary bodies to piece together a more cohesive understanding of how brittle structures evolve considering deformation kinematics, strength properties, and tectonic processes. In this research, I present an in-depth characterization of 14 major lunar grabens, with detailed descriptions of their geomorphology and geometry. By studying individual faults bounding these grabens, I address the evolution of faults: how faults grow, patterns they exhibit, loading conditions required for formation, and fault rock evolution over time. Graben formation on planetary bodies has previously been tied to dike intrusion and relates to an analysis of the King’s Bowl fracture system at Craters of the Moon National Monument and Preserve. A detailed investigation of fracture-lava interaction and dike intrusion was conducted by combining a field investigation with an Unpiloted Aerial Vehicle campaign. By studying the interaction of fractures and lava flow, I address the timing relationships for fracture formation as well as the topographic signatures caused by emplacement of a dike. These results are compared to models of dike intrusions with implications for the understanding of complex subsurface plumbing systems for Earth and similar sites on the Moon and other planetary bodies.