palaeogeothermal
/ˌpalɪə(ʊ)ˌdʒiːə(ʊ)ˈθəːml/ /ˌpeɪlɪə(ʊ)ˌdʒiːə(ʊ)ˈθəːml/Geology
adjective
Designating a temperature gradient which existed in the earth's crust at some time in the past.
Origin
1970s. From palaeo- + geothermal. Compare palaeogeotherm.