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Regional Carbonate Deposition Of The Pitkin Limestone (Chesterian): Washington And Crawford Counties, Arkansas, Robert E. Tehan
Regional Carbonate Deposition Of The Pitkin Limestone (Chesterian): Washington And Crawford Counties, Arkansas, Robert E. Tehan
Journal of the Arkansas Academy of Science
The Pitkin Limestone overlies black shale of the Fayetteville Formation and is the youngest Mississippian unit in the Paleozoic succession of northwest Arkansas. Five major fades have been delineated within the formation by apetrographic examination of samples collected from 17 measured sections: (1) oolith facies, (2) bioclast facies, (3) nodular limestone-shale facies, (4) mudstone facies, and (5) lime mud mound facies. The distribution of these facies in the Pitkin Formation suggests that Fayetteville terrigenous sedimentation was succeeded by the deposition of widespread oolith shoals and skeletal blanket sand bodies across the northern Arkansas structural platform. Sparse accumulations of lime mud …
Algal-Bryozoan Carbonate Buildups Within The Pitkin Limestone (Mississippian-Chesterian), Northwest Arkansas, Alex T. Warmath
Algal-Bryozoan Carbonate Buildups Within The Pitkin Limestone (Mississippian-Chesterian), Northwest Arkansas, Alex T. Warmath
Journal of the Arkansas Academy of Science
More than 14 biohermal buildups have been recognized within the Pitkin Limestone (Mississippian-Chesterian) in eastern Washington and western Madison Counties, northwest Arkansas. These buildups resemble previously described algal mounds in upper Pennsylvanian strata of the Midcontinent region, but differ in their faunal and floral constituents. The mounds are composed of calcilutite with variable amounts of spar and fossil allochemical grains. Associated flanking facies consist of mixed biosparite near the core, grading outward into oosparite. A few zones of shaly, poorly washed biomicrite containing rounded clasts bearing Archimedes fragments are interbedded with the flanking mixed biosparite facies. These clasts appear to …