Sulfur in volcanic arc magmas is an important tool for monitoring volcanic hazards and strongly influences the formation of porphyry ore deposits. Despite its importance, the extent to which subduction influences the sulfur content of arc magmas is debated. In this talk, I use direct measurements of sulfur isotope ratios and sulfur valence…

In this talk I discuss a simple law for the survival of geologic features following geologic forces over time. It is derived under minimal assumptions of isotropy and exponential decimation. The ratio law is apparent in the Earth Impact Database (2.4-0 Ga), the sedimentary datasets of Macrostrat (2.5-0 Ga; North America, Australia) and Ronov (1…

The decay of radioactive elements—like U, Th and K—produces heat and the dissipation of this heat from Earth's interior drives mantle convection and plate tectonics. Significant portions of Earth’s heating-producing elements (HPEs) are proposed to be sequestered within the continental crust, yet the HPE budget of the crust is uncertain, with…

Comprising ~71% of Earth’s surface, the ocean basins represent perhaps the most fundamental expression of plate tectonics. Yet, questions remain regarding the physical state of the oceanic asthenosphere (temperature, grain size, viscosity), abundance of melt and volatiles (H2O, CO2), and degree to which these factors influence plate motion and…

This talk explores two central aspects of rocky planetary interiors—water (Part I) and phase transitions (Part II), with the use of high-pressure experimentation, advanced thermodynamic methods, and statistical and machine-learning algorithms.

In Part I, I present a thermodynamic model for the water storage capacity of the solid…

The hypothesis of late veneer has been commonly employed to explain the origin of certain volatile elements and highly siderophile elements (HSEs: Ru, Rh, Pd, Re, Os, Ir, Pt, and Au) of bulk silicate Earth. However, the necessity of the late veneer is still in debate due to the lack of metal-silicate partition coefficients of HSEs under high…

Fluvio-lacustrine features on the martian surface attest to a climate that was radically different in the past. Ubiquitous valley networks and paleolakes across Mars’ southern highlands suggest that long-lived precipitation may have persisted up to 3.7 billion years ago. However, because climate models have difficulty sustaining a liquid…

Wet granular media can exhibit distinctly complex behavior. For example, one can sculpt a castle with wet sand, but not with dry sand or with sand submerged in water. It has been challenging to unravel these phenomena because the effective stresses transmitted through the particles have not been accessible to direct observation. In this talk, I…

The integration of computational thermodynamics and geodynamics is critical for a wide range of problems from mantle convection with consistent phase changes, to open system reactive transport during fluid/magma migration. These problems are strongly coupled, non-linear, involve large numbers of variables, and remain some of the outstanding…