Geochemical Evolution of Lake Uinta, Piceance Creek Basin, Colorado

摘要

1. Fe arrived in clastic sediment, resides in carbonates and pyrite (in basin center) 2. Mineralogy and geochemistry support this partitioning in basin center, not in margin 3. V/Cr suggests dysoxia through nearly full interval 4. Mo_(EF) and U_(EF) indicate more persistent anoxia, with rising, then falling enrichments, beginning before hypersaline conditions 5. Na_2O rise indicates arrival of hypersaline conditions, also indicated by diagenetic clay breakdown reactions 6. Chemostratification reflected in authigenic mineral suite and redox indicators - high organic preservation combined with diagenetic embrittlement.