Temperature-At-Depth Maps for the Conterminous U. S. and Geothermal Resource Estimates

TLDR

Temperature models are essential for evaluating nonconventional geothermal resources at regional to sub‑regional scales. The assessment used a global protocol, nearly doubled data points, refined thermal‑conductivity models, and added calibration wells to improve temperature‑at‑depth and heat‑flow calculations. The third‑generation assessment, using over 35,000 data sites, improves temperature‑at‑depth accuracy for the conterminous U.S.

Abstract

A third generation geothermal resource assessment has recently been completed for the conterminous US based on a revised heat flow map using over 35,000 data sites. Improvements include: nearly doubling the number of data points used in the analysis, more detailed thermal conductivity models for temperature-at-depth and heat flow calculations, and addition of a significant number of calibration wells as checks on the bottom hole temperature (BHT) correction. The results increase the accuracy of temperature-at-depth models for the conterminous US. These temperature models are the key input required for evaluating the nonconventional geothermal resources on a regional to sub-regional basis. The new resource assessment was prepared according to a proposed global protocol for estimating Enhanced/ Engineered Geothermal Systems (EGS) resource potential. A comparison of the new assessment approach with previous studies is provided, along with a discussion of the differences associated with the revised approach.