Paper No. 137-4
Presentation Time: 8:55 AM
EMERGENT BEHAVIOR OF SUBSURFACE MICROBE-ROCK-FLUID SYSTEMS RELATED TO CU, U, V, AND LI MINERALIZATION
Traditional and non-traditional resources in sedimentary basins are often studied in isolation, siloed by different industries (e.g., oil and gas, mineral, water, helium, and geothermal resources). Yet, interactions between these various fluid-rock systems are often required to explain their occurrence and gain a broader understanding of fundamental processes in sedimentary basins. Here, we combine multiple disciplinary perspectives and tools to understand the co-evolution of oil/gas, mineral (Cu, U, V, Li), helium, and water resources in the Paradox Basin in the Colorado Plateau. We show that early, compaction-driven migration of hydrocarbon- and H2S-bearing saline fluids from the Pennsylvanian Paradox Formation, during maximum burial, into overlying formerly red sandstones (e.g., Jurassic Wingate, Navajo and Entrada sandstones) contributed to reduced traps proximal to faults for accumulation of Cu and U during topographically- and density-driven circulation of more oxidized, Cu-bearing brines and U- and V-bearing groundwater. Relatively recent meteoric circulation, driven by rapid denudation of the Colorado Plateau (<10 Ma), dissolved gypsum in Paradox Fm salt walls and likely enhanced microbial oxidation of methane and higher chain hydrocarbons, coupled to bacterial sulfate reduction in shallow oil and gas reservoirs. Deeper meteoric circulation in basal aquifers partially flushed basinal brines and accumulated helium trapped by the overlying Paradox Formation evaporites. Li has been concentrated (up to 140 mg/L) in evaporated paleo-seawater derived brines within the Paradox Formation possibly from reaction with Li-bearing minerals in siliciclastic interbeds. Together these results highlight the coupling of various fluid-rock systems and importance of emergent behaviors – i.e., spatial and temporal interactions of independent factors leading to complex results that cannot be related to individual processes – to understand the myriad of resources within sedimentary basins.