See more from this Division: Topical Sessions
See more from this Session: Mixed Siliciclastic-Carbonate Systems: Mixing through Time and Space
Abstract:
1. Sedimentary structures consisting of climbing translatent stratification produced by migrating wind ripples of alternating laminations of ooids and siltsized quartz (pinstripe lamination) in the crossstrata, corrugated bedding planes, basal foresets tangential to the underlying surface, and adhesion structures at the base of the unit.
2. Petrographic evidence including coarseningupward sequences of broken and abraded ooid grains, dissolutioncompaction of grains in the vadose zone, fungal hyphae in the pore space, and intergranular micrite of vadose origin.
Relationships of the crossstratified ooid bodies with encasing lithofacies demonstrate that the intact crossstratified oolitic limestones were deposited as isolated bedforms on an emergent deflation surface during a regression of the Sundance Sea. Although the preservation potential of carbonate eolianites is low, partial meteoric lithification of the crossstrata before being subjected to lowenergy conditions during a subsequent transgression allowed for burial and preservation.
Misinterpretation of other crossstratified carbonates as subtidal marine grainstones may account for the scarcity of documented Mesozoic eolian carbonate examples. The evidence from the sedimentary structures, petrography, and stratigraphic relationships confirms the eolian origin of these strata, in specific; and provides a process for further interpretation of carbonate eolianites in the Mesozoic of the Western Interior, in general.
See more from this Division: Topical Sessions
See more from this Session: Mixed Siliciclastic-Carbonate Systems: Mixing through Time and Space