Contribution of the 2010 Maule Megathrust Earthquake to the Heat Flow at the Peru-Chile Trench

Abstract

The 2010 Maule earthquake was a megathrust event that occurred along the Peru–Chile Trench. The earthquake source can be modelled as a fault with two asperities with different areas and strengths. By employing a discrete fault model, where asperities are the basic elements, the event can be described as a sequence of three dynamic modes involving simultaneous asperity slip. Interaction between asperities by mutual stress transfer plays a crucial role during fault slip. With a careful choice of values for the model parameters, the mode durations, the slip distribution, the seismic moment rate and the final moment calculated from the model are found to be consistent with the observed values. An important amount of frictional heat is produced by an event of this size and is calculated by summing up the contributions of each asperity. The seismic event produces a heat pulse propagating through the Earth’s crust and contributing to the average heat flow in the region. The calculated heat production is equal to about 2×1017 J and the peak value of the heat pulse is equal to 6×10−3 mW m−2 or about 10−4 of the average surface heat flow density, with a characteristic diffusion time in the order of 106 a.

Review of discrete fracture network characterization for geothermal energy extraction

“…A look at recent literature that summarizes current knowledge of DFN with a focus on geothermal resources reveals a special issue (Mazzoli, 2022) with nine contributions that examine the link between structural geology and extraction of fluids. All nine contributions describe the tectonic structures of reservoir analogues (Filipovich et al, 2020;Bossennec et al, 2022;Dragoni and Santini, 2022), the fluid-rock interaction (Liotta et al, 2021;Gudmundsson, 2022), and heat flow computing and mapping (Santini et al, 2020;Majorowicz, 2021;Majorowicz and Grasby, 2021). Previous reviews in the field of geothermal energy have focused on the exploration of specific regions characterized by elevated geothermal gradients (e.g., Minissale, 1991;Breede et al, 2013;Manzella et al, 2018;Majorowicz, 2021).…”

Geothermal Energy and Structural Geology

“…Within this context, a reference model of the thermal structure at the crustal scale may also help to save time and money during subsequent, local geothermal assessments. This approach was applied by Dragoni and Santini [3] for a classic geothermal region, the Chilean-Peruvian Andes, and by Santini et al [4] for northern Albania. The analytical methodology used in these studies considered heat-flow density data coupled with geological constrains to obtain the surface heat flow, geotherms and isotherms in two dimensions.…”

“…The analytical methodology used in these studies considered heat-flow density data coupled with geological constrains to obtain the surface heat flow, geotherms and isotherms in two dimensions. An important amount of frictional heat is produced by earthquake faulting, in both the Albanian [3] and Andean [4] case studies, particularly for megathrust events such as the Maule earthquake that occurred along the Peru-Chile Trench in 2010 (the calculated heat production in this instance was ~2 × 1017 J [3]). This approach was further expanded in three dimensions by Santini et al [5] in their study of the geothermal setting of the Marche region (central Italy).…”