Newberry Volcano, a voluminous (500 km3) basaltic/andesitic/rhyolitic shield volcano located near the intersection of the Cascade volcanic arc, the Oregon High Lava Plains and Brothers Fault Zone, and the northern Basin and Range Province, has been the site of geothermal exploration for more than 40 years. This has resulted in a unique resource: an extensive set of surficial and subsurface information appropriate to constrain the baseline structure of, and conditions within a high heat capacity magmatically hosted geothermal system. In 2012 and 2014 AltaRock Energy conducted repeated stimulation of an enhanced geothermal systems (EGS) prospect along the western flank of the Newberry Volcano. A surface based monitoring effort was conducted independent of these stimulation attempts in both 2012 and 2014 through a collaboration between NETL, Oregon State University and Zonge International. This program included utilization of 3-D and 4-D magnetotelluric, InSAR, ground-based interferometric radar, and microgravity observations within and surrounding the planned EGS stimulation zone. These observations as well as borehole and microseismic stress field and location solutions provided by AltaRock and its collaborators, in combination with well logs, petrologic and geochemical data sets, LIDAR mapping of fault traces and extrusive volcanics, surficial geologic mapping and seismic tomography, have resulted in development of a framework, subsurface geologic model for Newberry Volcano. The Newberry subsurface geologic model is a three-dimensional digital model constructed in EarthVision that enables lithology, directly and remotely measured material properties, and derived properties such as permeability, porosity and temperature, to be coregistered. This provides a powerful tool for characterizing and evaluating the sustainability of the site for EGS production and testing, particularly within the data-dense western portion of the volcano. The model has implications for understanding the previous EGS stimulations at Newberry as well as supporting future research and resource characterization opportunities. A portion of the Newberry area has been selected as a candidate site for the DOE FORGE (Frontier Observatory for Research in Geothermal Energy) Program through a collaboration between Pacific Northwest National Laboratory, Oregon State University, AltaRock Energy and additional partners. Thus, the conceptual geologic model presented here will support and benefit from future enhancements associated with that effort. --Mark-Moser et al. 2016
NIPER-540
This data submission includes several data components that were used to develop a conceptual model and power capacity-estimates of two low-temperature geothermal resources that define geothermal prospect A at Hawthorne, Nevada. Data are sourced from a combination of legacy publicly-available data and more recent data acquisition conducted by the US Navy Geothermal Program Office (2008-2013) and the Great Basin Center for Geothermal Energy at the University of Nevada, Reno (2008-2010). Data sets include compiled fluid geochemistry data, down-hole temperature logs for wells in the vicinity of prospect A, 2 meter temperature survey data, temperature-spinner logs acquired in well HWAAD-2A, fracture picks from image log data acquired in wells HWAAD-2 and HWAAD-3, and X-Ray Diffraction (XRD) analyses on cuttings from wells HWAAD-2A and HWAAD-3. These data have been reviewed for errors and inconsistencies, but it is possible that few errors could still remain. The resource conceptual model and power capacity estimates are included in the final report to the US Department of Energy, and are presented in a manuscript by Ayling and Hinz. A link to the manuscript published in Geothermics is linked below in this submission.
The PoroTomo team has completed inverse modeling of the three data sets (seismology, geodesy, and hydrology) individually, as described previously. The estimated values of the material properties are registered on a three-dimensional grid with a spacing of 25 meters between nodes. The material properties are listed an Excel file. Figures show planar slices in three sets: horizontal slices in a planes normal to the vertical Z axis (Z normal), vertical slices in planes perpendicular to the dominant strike of the fault system (X normal), and vertical slices in planes parallel to the dominant strike of the fault system (Y normal). The results agree on the following points. The material is unconsolidated and/or fractured, especially in the shallow layers. The structural trends follow the fault system in strike and dip. The geodetic measurements favor the hypothesis of thermal contraction. Temporal changes in pressure, subsidence rate, and seismic amplitude are associated with changes in pumping rates during the four stages of the deployment in 2016. The modeled hydraulic conductivity is high in fault damage zones. All the observations are consistent with the conceptual model: highly permeable conduits along faults channel fluids from shallow aquifers to the deep geothermal reservoir tapped by the production wells.
Conceptual model for the Newberry Caldera geothermal area. Model is centered around caldera and evaluates geologic information in tandem with some geophysical datasets to derive a conceptual subsurface model. Includes: Geologic information from the USGS geologic map of Newberry and cross-sections from Sonnenthal et al, 2012 West flank seismic body representing a fractional change in seismic velocity of 0.1, defined in Beachly et al., 2012 and Heath et al., 2015 West flank gravity body "granite" that represents a gravity anomaly identified in Waibel et al., 2014 (DOE document, figure 35) Magma chamber defined seismically, found in Heath et al., 2015 Ring fracture fault intrusions Various faults sourced from the USGS geologic map of Newberry, Grasso et al. 2012's fault and fissure mapping
Conceptual model for the Newberry Caldera geothermal area. Model is centered around caldera and evaluates multiple geophysical datasets to derive a conceptual subsurface model. Includes: Conductor layer based on transient electromagnetic data from Fitterman et al., 1988 (figure 10) Base of conductor layer based on MT conductor values found in Waibel et al., 2014 (DOE document, figure 38) Resistor layer based on magnetotellurics from Fitterman et al., 1988 (figure 13). Seismic intrusives layer representing a smoothed version of 5.5 km/s seismic velocity layer defined in Beachly et al., 2012 West flank seismic body representing a fractional change in seismic velocity of 0.1, defined in Beachly et al., 2012 and Heath et al., 2015 West flank gravity body "granite" that represents a gravity anomaly identified in Waibel et al., 2014 (DOE document, figure 35) Magma chamber defined seismically, found in Heath et al., 2015 Ring fracture fault intrusions Various faults and geologic layers