Three-Dimensional Resistivity and Magnetic Imaging of Vapor Dominated Areas in Yellowstone National Park.
Laboratoire(s)/équipe(s) du LabEx OSUG impliqué(e.s) : ISTERRE, USGS Menlo Park, CA, Colorado School of Mines, Golden, CO
Porteur du Projet : Claire Bouligand
We propose to carry out an original experiment coupling dense electric resistivity and magnetic measurements of two well-studied vapor-dominated areas in Yellowstone NP ; the Obsidian Pool (Mud Volcano) and the Solfatara Plateau thermal areas. Hydrothermal alteration and circulation of thermal fluids modify both the electric resistivity and the magnetization of rocks offering a base for a joint inversion. Data inversion will be performed using cross-gradient technique and introducing a normalized "alteration index" used to identify the position of conduits channeling the hydrothermal fluids. The results will provide a high-resolution 3-D image of the subsurface. This imaging and numerical modeling of multi-phase flow of CO2 and water will be used to better understand the physics of fluid and heat transport in two-phase flow conditions, and to quantify the effects of the dissolved and gaseous CO2 on the bulk electric resistivity.
Soutien attribué : 8 000 € en 2015