Compaction-Driven Groundwater Flow and Heat Transfer in Intracratonic Sedimentary Basins and Genesis of the Upper Mississippi Valley Mineral District (Hydrology, Migration, Petroleum, Ore Deposits, Numerical Models)

A new numerical method allows calculation of compaction-driven groundwater flow and associated heat transfer in evolving sedimentary basins. A calculation of compaction-driven flow during evolution of an idealized intracratonic sedimentary basin including a basal aquifer predicts slow groundwater movement over long time periods. Fluids in shallow sediments tend to move upward toward the sedimentation surface, and deeper fluids move laterally. The hydraulic potential gradient with depth reverses itself near the basal aquifer, and fluids in this area have a tendency to migrate obliquely into stratigraphically lower sediments. Only small excess pressures develop, suggesting that intracratonic basins are not subject to overpressuring during their evolutions. Due to the small fluid velocities, heat transfer remains conduction-dominated and the geothermal gradient is not disturbed. Variational studies show that excess hydraulic potentials, but not fluid velocities, depend on assumptions of permeability, and that both excess potentials and velocities scale with sedimentation rate. These results cast doubt on roles of compaction-driven flow within intracratonic basins in processes of secondary petroleum migration, osmotic concentration of sedimentary brines and formation of Mississippi Valley-type ore deposits.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Geology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Bethke, Craig Martin

• Hydrology

Identifier

(UMI)AAI8511580

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/71137