Joint Time-Lapse Acquisition and Inversion of Passive Seismic and Magnetotelluric Data for Monitoring Reservoir Processes at the Geysers Geothermal Field
A field demonstration at The Geysers will be carried out to evaluate the value added by applying this technology.
Lawrence Berkeley National Laboratory
Recipient
Berkeley, CA
Recipient Location
9th
Senate District
14th
Assembly District
$1,661,032
Amount Spent
Completed
Project Status
Project Result
Three sets of seismic and magnetotelluric (MT) data have been collected and processed in 2021, 2022, and 2023. The seismic and MT data have been inverted separately for the three different times to produce images and as well the research team have implemented and applied a joint inversion workflow which enforces the seismic and MT images to show structural similarity. This has shown to significantly enhance the resolution of the MT images. The resulting images have been brought into a geological modeling software package to help interpret where changes are occurring in the reservoir in terms of water versus steam saturation.
The Issue
In operating geothermal fields, it is inherently difficult to image the movement of water and steam in a fractured geothermal reservoir in time and three-dimensional space. Tracer tests provide ground truth information about inter-well connectively, but they do not directly reveal the flow paths in the regions between the wells. Microseismicity mapped in three-dimensions can provide valuable information about fluid movement, but it is possible for water and steam to move through the fractured rock mass without triggering microseismicity, as well for microseismicity to be triggered without fluids.
Project Innovation
This project will demonstrate the advantages of concurrently acquiring time-lapse magnetotelluric and passive seismic data over a producing geothermal reservoir. The data will be jointly inverted for images of resistivity and seismic velocities using workflows and algorithms that enforce structural similarity constraints between the different physical properties, and subsequently correlating the spatio-temporal information in the joint-inversion geophysical images to working reservoir models. The technical advancements of this project are provided via concurrent monitoring of time-lapse changes in both resistivity and seismic velocity and the joint inversion of the multi-physics data. Ultimately, these images can be used for better estimates of rock properties and spatial distribution of steam and water at depth, for more accurate reservoir modeling and monitoring which will lead to more accurate placement of production wells. A field demonstration at The Geysers has been carried out to evaluate the value added by applying this technology.
Project Goals
Project Benefits
This Agreement will lead to technological advancement and breakthroughs to overcome barriers to the achievement of the State of California's statutory energy goals by assisting the continued growth of California's broad portfolio of renewable energy, including geothermal, as required to achieve the goals of SB 350. This project will demonstrate the advantages of concurrently acquiring time-lapse magnetotelluric and passive seismic data over a producing geothermal reservoir, jointly inverting these time-lapse data for images of resistivity and seismic velocities using workflows and algorithms that enforce structural similarity constraints between the different physical properties, and subsequently correlating the spatio-temporal information in the joint-inversion geophysical images to working reservoir models to update these models and to adjust injection and production rates.
Affordability
Determining the siting of new injection or production wells in a geothermal field holds high financial risk. This technology will improve imaging of the distribution of subsurface water and steam, for better informed decisions.
Environmental Sustainability
Differentiation of the distribution of water and steam in the subsurface will reduce the number of geothermal production and injection wells that need to be drilled.
Energy Security
California has a large geothermal resource potential. Optimal management of this source of clean energy through remote subsurface imaging technologies provides energy security for future generations.
Key Project Members
David Alumbaugh
Subrecipients
U.S. Geological Survey
EMR Solutions & Technology LLC
Jarpe Data Solutions
Match Partners
U.S. Geological Survey
