Origin of late dolomite cement by CO2-saturated deep basin brines; evidence from the Ozark region, central United States@ with Suppl. Data 91-10

• Published in: Geology (Boulder) 1991-04, Vol.19 (4), p.348-351
• Main Authors: Leach, D. L, Plumlee, G. S, Hofstra, A. H, Landis, G. P, Rowan, E. Lanier, Viets, J. G
• Format: Article
• Language: English
• Subjects: basins; boiling; brines; carbon dioxide; carbonate rocks; carbonatization; cement; cementation; diagenesis; dolomitization; dolostone; eastern Kansas; Economic geology; fluid inclusions; framework silicates; galena; geochemistry; geologic thermometry; inclusions; Kansas; late diagenesis; metal ores; mineral deposits, genesis; mississippi valley-type deposits; Missouri; ore-forming fluids; Ozark Mountains; paleosalinity; precipitation; processes; quartz; saturation; sed rocks, sediments; sedimentary basins; sedimentary petrology; sedimentary rocks; sedimentation; silica minerals; silicates; southwestern Missouri; sphalerite; sulfides; United States; water
• ISSN: 0091-7613; 1943-2682
• DOI: 10.1130/0091-7613(1991)019<0348:OOLDCB>2.3.CO;2

Studies of fluid inclusions in regionally extensive late dolomite cement (LDC) throughout the Ozark region show that CO2 effervescence was widespread during dolomite precipitation. On the basis of quantitative analyses of inclusion fluids, reaction-path modeling shows that LDC with trace amounts of sulfides can be deposited by effervescence of a CO2-saturated basin brine as it migrates to shallower levels and lower confining pressures. This precipitation mechanism best explains occurrences of LDC in the Ozark region and may account for LDC found in sedimentary basins worldwide.