Current funding and projects

CSEDI: Constraining the mechanisms of melt transport, storage, and crustal contamination from temporal geochemical variations in monogenetic vents
PI: John Lassiter (Department of Geological Sciences, University of Texas at Austin)
CoPI: Jamie Barnes (Department of Geological Sciences, University of Texas at Austin)
Grant number: EAR – 1301621
Description: This study integrates numerical modeling of melt transport, storage, crustal interaction, and eruption with geochemiscal time series data in order to determine the origin of systematic timeprogressive compositional variations observed in many monogenetic vent sequences and in other longduration eruption sequences. The project will test if the compositional trends are due to mixing of melts generated from distinct components or lithologies, such as small scale heterogeneities, in the mantle source region or due to fractional crystallization and crustal assimilation during storage in crustal sills. 

Hydrogeochemical dynamics of natural carbon dioxide fields
CoPI: David DiCarlo (Department of Petroleum and Geosystems Engineering, University of Texas at Austin)
Grant number: EAR – 1215853
Description: The objective of this proposal is to estimate the longterm convective dissolution rate of carbon dioxide (CO2) at the Bravo dome CO2 field. This will allow us to test current numerical models of geological carbon dioxide storage and to strengthen our confidence in their predictions of longterm storage security. Convective dissolution of CO2 into the brine, due to the increase in brine density with CO2 concentration, has been identified as a key trapping mechanism ensuring the safe longterm storage of CO2. A field based estimate of the longterm dissolution rate would greatly increase our confidence in numerical predictions, but currently no such estimate is available. Therefore, we propose to combine recent geochemical observations from the Bravo dome CO2 field in New Mexico with fluid dynamic models of CO2 migration and convective CO2 dissolution to provide such estimates. We will develop a verticallyintegrated model for the geochemical evolution of the CO2 plume in realistic reservoir geometries. Comparisons between the observed spatial geochemical variations and model predictions will be used to invert for the convective dissolution rate. The parametrization of the convective dissolution term in these models is critical and a central component of our proposal is the experimental quantification of the convective dissolution rates in heterogeneous media and realistic geometries. In particular, we hope to provide the first three dimensional Xray imaging of the convective structures in a porous medium. The calibrated dynamic models can then be used in forward models of geological CO2 storage in similar formations. 

CMG: Robust Numerical Methods for MultiPhase DarcyStokes Flow in Heterogeneous and Anisotropic Partially Molten Materials
CoPI: Todd Arbogast (Department of Mathematics, University of Texas at Austin)
Grant number: EAR1025321
Description: The dynamics of partially molten systems control the internal structure of planetary bodies. Partially molten materials are highly nonlinear geosystems where chemical reactions, heat transfer, and mechanical deformation are tightly coupled by multiphase flow and require the development of robust numerical discretizations and solution strategies. The project will focus on the three following closely related themes: (1) Extension of the mathematical description to the dynamics of threephase flow in partially molten systems with an additional fluid phase in the pore space. The resulting threephase flow model will allow a selfconsistent study of fluxmelting in subduction zones. (2) The development and analysis of a robust mixed fi nite element discretization for the multiphase DarcyStokes system that describes partially molten porous media. These methods have been successful in both limiting cases: heterogeneous and anisotropic Darcy flow as well as incompressible Stokes flow. (3) The development of a reactive transport model for partially molten systems and the analysis of chromatography in partially molten materials. High temperatures allow chemical reactions to remain close to equilibrium, but also make it necessary to treat both the liquids as well as the solid as liquid and solidsolutions. These new models and numerical techniques provide the building blocks of the development of a robust numerical simulation tool for melting, geochemical evolution, and melt transport in the Earth’s mantle, and other partially molten systems 

CoPI: Todd Arbogast (Department of Mathematics, University of Texas at Austin)
Grant number: EAR1025321
Description: Tempora cum causis Latium digesta per annum lapsaque sub terras ortaque signa canam. excipe pacato, Caesar Germanice, voltu hoc opus et timidae derige navis iter, officioque, levem non aversatus honorem, en tibi devoto numine dexter ades. 
Independent funding of graduate students

Trap integrity in salt basins; sub‐salt imaging and seal vs. pore pressure challenges
Graduate student: Soheil Ghanbarzadeh
Grant type: Statoil Graduate Fellowship
Description: Experimental, theoretical and field evidence suggest that brine (and oil) can wet rock salt surfaces at higher pressures and temperatures to form a percolating network that may act as flow conduits. This is contrary to the common view that salts in sedimentary basins always act as a seal. The main objective of this proposal is to formulate a theoretical model for interfacial topology that combines crystal growth and equilibration of multicrystal boundaries, which can be solved numerically to yield a 3D equilibrium solidliquid interfacial surface in realistic geometries. This will enable us to investigate opening of pore space networks for different wetting angles and pressure/temperature in rock salt. Pore configurations determine a wide range of petrophysical properties such as permeability and capillary entry pressure. Better knowledge of petrophysical properties of salt vs. depth could improve drilling operations in salt. Further knowing connectivity/permeability can help improving subsalt imaging by tuning in the input velocity models for seismic imaging.
Publications: Ghanbarzadeh et al. (2014) 
Past funding and projects

The interpretation of geochemical patterns through the hyperbolic theory for reactive transport in porous media
Grant number: ACSPRF #51230 DNI8
Description: Reactive transport has been recognized as fundamental mechanism for pattern formation in the geological sciences. It determines the chemical evolution of pore fluids as well as the mineralogy and petrophysical properties of the rocks. A dominant feature reaction fronts is the evolution of a sequence of different types of chemical waves that travel with distinct velocities and separate regions of different composition. The theory of systems hyperbolic partial differential equations provides a unifying concept that allows the analysis of the basic structure of these patterns in multicomponent and multiphase systems, including surface and classical reactions as well as multiphase flows with partitioning. A key element of the theory is the identification of composition paths that describe the variation in system composition due to a particular chemical wave, and hence reaction mechanism.
Publications:
Prigiobbe et al. (2011), Prigiobbe et al. (2013), Venkatraman et al. (2014) 

Characterizing the timedependent flux of CO_{2}saturated brine up a leaky well
Graduate student: Nicolas Huerta
Grant type: U.S. DOE – National Energy Technology Laboratory (NETL) Student Internship
Description: The goal of this project is to characterize the fundamental phenomena controlling time dependent leakage of CO2 up a leaky well. This work is in collaboration with efforts at NETL and other national laboratories to provide parameters for a higher order risk assessment model to quantify the risk of adverse effects due to geologic carbon storage. This work comprises experiments and numerical modeling to estimate change in leakage rate over time. Specifically, this work looks at the coupling between transport of CO2satuared brine along a cement fracture with the chemical processes of dissolution of some cement phases and precipitation of secondary phases. How the system evolves in time is of critical importance as the coupling determines how the leak will evolve in time, either by selfsealing or selfenhancing.
Publications: Huerta et al. (2012) 
Site Last Modified: July 25, 2014