FACIES ARCHITECTURE OF SHALLOW MARINE DELTAIC SEDIMENTS AND ASSOCIATED CHANNELS IN A STORM-DOMINATED ENVIRONMENT, TURONIAN FERRON SANDSTONE, UTAH

Numerous facies architectural reconstructions of the Turonian Ferron Sandstone have been generated in previous well-documented studies. This study’s focus is to analyze the facies architecture of shallow marine deltaic sediments in Parasequence 5a of the Ferron as well as analyze the extent of fluvial influence within the associated marine deposits. Preliminary studies examining the fluvial influence within delta front sandstones have interpreted the channels as distributary channels, but several more recent evaluations show previously interpreted distributary channels as being multi-storey incised valley fill deposits. In this study, architectural elements were determined using data from ten detailed stratigraphic logs, paleocurrent measurements, and bedding thicknesses. Stratigraphic logs were measured on a centimeter to meter scale in the southern region of the Ferron Sandstone in Hanksville, Utah. Seven distinct facies were identified in correlation profiles and it is interesting to note the presence of sauropod footprint fossils observed in three measured sections. Analysis of facies architecture reveals three small 1-2m thick stacked distributary channels with numerous accreting beds in the Southern Ferron. Bounding surfaces including dunes, cross set boundaries, bars, channel bases and a channel belt were identified as 2^nd to 6^th order. Each channel contains approximately 1-2 bars just over a metre in thickness. Paleocurrent data obtained from crossbeds suggest flow direction to the southeast. Furthermore, channel depth to basin depth ratios of 0.5-0.75m taken where the channel is thickest indicate this area is on the medial side of a delta system, where only some topsets are preserved.