This paper presents the results of a study to determine the potential for coproduced critical minerals and geothermal energy generation in offshore production. The objective was to focus on high temperature produced water in locations likely to contain critical minerals such as lithium, rare earth elements (REEs), platinum group metals, arsenic, and others. The scope is global, and the offshore locations graded to prioritize in terms of geothermal energy and concentration of critical minerals.
The method involved studying the tectonic history of the offshore production of the world and conducting reconnaissance basin analysis to create general maps of heat and location of critical minerals. A study of all publications that included information about the geochemical composition of reservoir fluids as well as samples / cores was also incorporated. Where available, geothermal information was gained by collecting the bottomhole temperatures of producing and test wells.
The preliminary results indicate that some offshore production does have the potential to be converted to producers of geothermal energy, to be consumed locally, depending on needs and infrastructure. In some cases, platforms can be converted to battery charging stations. With respect to critical minerals, preliminary results have identified offshore producing fields with a potentially commercial concentration of critical minerals in the produced brine / reservoir fluids. Further study is being conducted to define the type and concentration of critical minerals, and to recommend the ideal production method for each high-ranking prospect.
Certain offshore reservoirs have the potential to coproduce geothermal energy and reservoir fluids. Further, there are locations in offshore basins that may have commercially producible levels of critical minerals. Novel methods of producing and concentrating brine will be necessary offshore to work within the constraints of the locally generated energy, and to preserve and protect the environment.