On the use of gravity data in delineating geologic features of interest for geothermal exploration in the Geneva Basin (Switzerland): prospects and limitations

Abstract

Gravity data retrieved from the Bureau Gravimétrique International and the Gravimetric Atlas of Switzerland have been used to evaluate their applicability as a subsurface investigation tool to assess key geological features in support of the geothermal exploration in the Geneva Basin (GB). In this context, the application of an effective processing workflow able to produce reliable residual gravity anomalies was implemented as a crucial first step to investigate whether and to what level gravity anomalies can be correlated to geologic sources of geothermal interest. This study focusses on the processing workflow applied to publicly available gravity data, including the quantification of the uncertainty. This was then also used for first-order 2D forward gravity modelling. The resulting residual anomalies demonstrate the potential use of gravity investigations for geothermal exploration in sedimentary basins, and also reveal areas of significant, irreparable misfit, which calls for the use of complementary data and 3D subsurface structural knowledge. The results of such investigations will be presented in subsequent studies.

Utilization of Gravimetric Satellite Data for Delineating of Subsurface Model of The Purwokerto-Purbalingga Groundwater Basin

“…Geophysical modeling of the groundwater basin was carried out in two dimensions on three trajectories over the residual gravity anomaly map with the geographical position, as shown in Figure 6. The trajectories are AA′ with a length of 17,686 m, BB′ with a length of 19,830 m, and CC′ with a length of 22,387 m. The modeling of the Purwokerto-Purbalingga Groundwater Basin was based on its density values (Guglielmetti et al, 2021). The obtained sub-surface models for all trajectories are shown in Figure 7 to Figure 9, while its interpretation results are depicted in Table 2.…”

Visualization Analysis on the Current Status and Development Trend of Geothermal Research: Insights Into the Database of Web of Science

“…The research themes were divided into four groups (Figure 9): a) motor themes (first quadrant): high concentration and high density, reflecting essential, and well-developed themes; b) niche themes (second quadrant): high concentration and low density, reflecting important but not welldeveloped themes; c) emerging or declining themes (third quadrant): low centrality and low density, reflecting the themes that are about to disappear, or maybe a frontier theme that will emerge in the future; and d) basic themes (fourth quadrant): low centrality and high density, reflecting the themes that have been well-developed with little prospect in the future and usually refers to the basic concept, such as a search term. As shown in Figure 9, the theme of the first quadrant is "geothermal exploration," which indicates that the exploration and development of geothermal resources has received close attention and will continue to be carried out (Zaher et al, 2018;Ars et al, 2019;Thomas et al, 2019;Guglielmetti and Moscariello, 2021). The second quadrant is "geothermal water" and "enhanced geothermal system" enhanced geothermal systems.…”

Using Dark Fiber and Distributed Acoustic Sensing to Characterize a Geothermal System in the Imperial Valley, Southern California

“…For example, heat flow anomalies, derived from temperature measurements in shallow boreholes, can be used to locate and outline potential geothermal fields (Burton‐Johnson et al., 2020; Fahnestock et al., 2001; Kratt et al., 2008; Zehner et al., 2012). Gravity surveys can be used to study the depth of fill in intermontaine valleys, locate intrusive masses of rock and delineate geothermal features (Atef et al., 2016; Guglielmetti & Moscariello, 2021). A combination of resistivity profiles, derived from active or passive electromagnetic (EM) surveys, and heat flow measurements from temperature gradient wells are often used to search for zones likely to host permeable geothermal reservoirs sealed with an overlying clay cap (Anderson et al., 2000; Gao et al., 2018; Munoz, 2014).…”