Figure 7 - uploaded by Carlos A. Vargas
Content may be subject to copyright.
Global geothermal gradient map estimated by CPD (units °C/km). The red lines correspond to tectonic plate boundaries.
Source publication
The presence of sedimentary sequences located at temperatures ranging between 60 and 120 °C has permitted the identification of hydrocarbon accumulation patterns of economic importance. This thermal range is identified as the “Golden Zone”, where there is a potential co-existence of the petroleum system elements that supports a minimal degree of de...
Citations
... In recent years, researchers in Norway have developed the concept of the 'Golden Zone' (GZ) for hydrocarbon exploration (e.g., Buller et al., 2005;Nadeau, 2011;Angulo and Vargas, 2022;Nadeau et al., 2023). The GZ refers to a depth range of liquid hydrocarbon window corresponding to temperatures from 60 • C to 120 • C and thermal maturity of vitrinite reflectance from 0.6% to 1.2% Ro (Bjørkum and Nadeau, 1998). ...
... Table 1 is used to quickly address the minimum, maximum, and mean depth range throughout the dataset. One observation is that the mean depths reported from the models of Li et al., (2018) and Angulo and Vargas, (2022), both of which use versions of the EMAG magnetic model, is that these two studies tend to yield shallow CDP depths. Figure 7a and 7b, reveal that in general the LithoRef18 depths to 450C are deeper than the CDP models within the cratonic areas and conversely LithoRef18 is shallower in the younger orogenic regions on the eastern and western margins. ...
Theory In the current geo-political energy environment, many governments around the world are looking towards alternative energy sources to assist with the phasing out of fossil fuels. As a result, geothermal energy has seen an intensification of interest because it may provide cost-competitive, carbon-free, always available renewable energy, while requiring significantly less land than other energy sources. Increased exploration of geothermal resources is occurring along with a boom in technological innovations, with an eye towards exploration of deeper and hotter geothermal resources. To explore for supercritical geothermal resources, an improved understanding of subsurface temperatures and pressures is needed. Successful characterization of the depth to critical isotherms and potential resource density requires a better understanding of the thermal structure of the entire lithosphere, yet actual hard data remains sparse. The lack of data to constrain the models leads to uncertainties in the global characterization of thermal anomalies. Using global lithosphere models (LithoRef18, Afonso et al., 2019), we examine and compare the predicted surface heat flow models and the computed depths to the 450 C isotherm. The results from these models allow us to characterize the first-order nature of the thermal structure of the Earth's lithosphere and the geodynamic environment these thermal anomalies occur. In addition, we explore uncertainties in the depth and spatial location of the thermal anomalies between models and investigate how to develop a thermal model that can be used for the delineation and size of next-generation, superhot rock geothermal opportunities.
In the current global geo-political environment, many governments are looking towards alternative energy sources to assist with the phasing out of fossil fuels. As a result, geothermal energy has seen an intensification of interest because it provides cost-competitive, low-carbon, always available renewable energy, while requiring significantly less land than other energy sources. Increased exploration of geothermal resources is occurring in tandem with a boom in technological innovations, with an eye towards exploration of deeper and hotter geothermal resources. To explore for supercritical geothermal resources, an improved understanding of subsurface temperatures and pressures is needed. Successful characterization of the depth to critical isotherms and potential resource density requires a better understanding of the thermal structure of the entire lithosphere, yet hard data to constrain these models remains sparse, leading to uncertainties in the global characterization of thermal anomalies. Using global lithospheric models (LithoRef18, Afonso et al., 2019), we examine and compare the predicted surface heat flow models and the computed depths to critical isotherms. The results allow us to characterize the first-order nature of the thermal structure of the Earth's lithosphere and the geodynamic environment in which these thermal anomalies occur. In addition, we explore uncertainties in the depth and spatial location of the thermal anomalies between models and investigate the challenges of developing a thermal model that can be used for the delineation and estimation of next-generation, superhot rock geothermal opportunities.
