Supplemental Material: Integrated geologic and geophysical modeling across the Bartlett Springs fault zone, northern California: Implications for fault creep and regional structure
Authors: Langenheim V.E. , al. et 
Published: September 2023

<p>Figure 2 (interactive). Use radio buttons to toggle between different maps. Simplified geology (A), aeromagnetic anomalies (B), isostatic gravity anomalies (C), topography and place names (D), and magnetic potential anomalies (E) of the study area. Black lines show locations of modeled sections shown in Figure 3. Blue outlines in panels B, C, and D show lakes or reservoirs. Geology in A is from Jennings (1977), McLaughlin et al. (2018), Melosh et al. (2022), and Langenheim et al. (2013). Aeromagnetic anomalies in B, gravity data in C, and magnetic potential data in E are from Langenheim et al. (2023). Topographic data are from U.S. Geological Survey (2019). Dashed green and gray lines in D show locations of a seismic-refraction profile (Godfrey et al., 1997) and seismic-reflection profile (Ramirez, 1992; Constenius et al., 2000), respectively. Dashed blue line nearly coincident with the trace of the Bartlett Springs fault zone is line of section shown in Figure 5. Alinement array locations are from McFarland et al. (2016); GPS station locations are from Murray et al. (2014); repeating earthquakes are confirmed locations from Shakibay Senobari and Funning (2019); geothermal well locations are from California Department of Oil, Gas, and Geothermal Resources (2022).</p>
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<p>Figure 4 (interactive). Use radio buttons to toggle between different plots. Comparison of our model of magnetic bodies along profile 5 with previously published models approximately along profile 5. See Figure 2D for location of profile 5. Small black dots in upper panel are gridded magnetic values along profile 5 (Langenheim et al., 2023). Red, blue, and magenta curves are predicted magnetic anomalies from sources shown in A, B, and C, respectively. Numbers in polygons in A–C are values of magnetization (in A/m). BSFZ—Bartlett Springs fault zone. (A) Model from this study. (B) Model in Godfrey et al. (1997). (C) Model in Jachens et al. (1995). (D) Seismic velocity model from Godfrey et al. (1997). (E) Density model from Godfrey et al. (1997); numbers are densities (in kg/m<sup>3</sup>).</p>
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<p>Figure 5. (interactive). Use radio buttons to toggle between different sections. Comparison of creep measurements (upper panel) and modeled extent of serpentinite with creep models along the Bartlett Springs fault zone (bottom panel). See Figure 2D for location of section. In upper panel, red and blue circles are creep rates from alinement arrays and InSAR data, respectively (Johnson et al., 2022a, 2022b). Thin vertical lines are error bars. In bottom panel, numbers denote where cross sections modeled in this study intersect line of section; inverted red triangles are locations of alinement arrays with station names (see Fig. 2 for locations). (A) Modeled extent of serpentinite within Bartlett Springs fault zone, shown by purple vertical lines. Dark blue crosses and magenta-outlined white circles show seismicity 1 < M < 3 (NCEDC [2021] using the methods of Waldhauser and Schaff [2008] and Waldhauser [2009]) and confirmed repeating earthquakes (Shakibay Senobari and Funning, 2019), respectively, within 5 km of profile. (B) Creep model of Lienkaemper et al. (2014). (C) Creep model of Murray et al. (2014). In B and C, blue extents denote locked zones, and warmer colors indicate areas with higher creep rates.</p>