Procesos tafonómicos en una encrinita regional pensilvánica (Atokano), Sonora, México

Abstract

Crinoids have an extensive fossil record and were a major component in Paleozoic marine communities; encrinites are common crinoid accumulations where specimens are totally disarticulated from the Ordovician to the Jurassic. In Sonora, Mexico, the crinoid skeleton was altered during diagenesis and replaced by silica. The corrasion was high; the incrustation low and there is evidence of dissolution and compaction. This is a sedimentological type accumulation in a high energy environment of allochthonous organism transported in a debris flow, deposited below the storm wave base in an outer ramp. Our results can be correlated with regional encrinites prevalent in the Pennsylvanian cyclothems of North America.