Morphologic Clues to the Origins of Iron Oxide–Cemented Spheroids, Boxworks, and Pipelike Concretions, Navajo Sandstone of South-Central Utah, U.S.A.

Abstract

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Life and Liesegang: Outcrop-Scale Microbially Induced Diagenetic Structures and Geochemical Self-Organization Phenomena Produced by Oxidation of Reduced Iron

“…(2) Excess acid is neutralized by dissolution of siderite tending to drive the reaction from left to right. This mechanism of siderite oxidation is very similar to one we proposed for iron-oxide concretions in the Navajo and Dakota Sandstones (Loope et al, , 2011Weber et al, 2012).…”

Hydrocarbon-induced diagenetic alteration of the Permian White Rim Sandstone, Elaterite Basin, southeast Utah

“…Upon oxidation by contact with another fluid, such as meteoric groundwater, solubilized iron oxide minerals are reprecipitated as porefill cement (Chan et al, 2000Chan and Parry, 2002;Bowen et al, 2007). It is also possible for precursor minerals (e.g., pyrite) to be precipitated early and later oxidized to iron oxide minerals (Dinwiddie et al, 2011;Loope et al, 2011;Chan et al, 2012;Potter-McIntyre et al, 2014).…”

Scientific drilling and downhole fluid sampling of a natural CO<sub>2</sub> reservoir, Green River, Utah

“…This has variously been attributed to bleaching by buoyant hydrocarbons and methane rich brine (Beitler et al, 2003(Beitler et al, , 2005Chan et al, 2000;Garden et al, 2001;Parry et al, 2004Parry et al, , 2009) and by dense CO 2 -charged brine containing methane or sulfide reductants (Loope et al, 2010(Loope et al, , 2011Potter-McIntyre et al, 2013;Wigley et al, 2012, Figure 6. (A) Bleached basal sandstones of the Entrada Sandstone hosting CO 2 charged fluids.…”