Valleys, facies, and sequence stratigraphy of the Ferron Notom Delta, Capital Reef, Utah

The Turonian-Coniacian Ferron Sandstone is the first significant elastic tongue prograding from the thin-skinned Sevier Orogenic belts into the western interior foreland basin after the Greenhorn sea-level maxima. The Ferron Notom Delta, one of the Ferron wedges, is exposed three dimensionally in the Henry Mountains region, Utah. This dissertation attempts to: (1) subdivide the complex in a sequence stratigraphic perspective, and (2) evaluate the existing nonmarine sequence stratigraphic and delta asymmetry models.;Incised valleys are developed in the younger two sequences. The youngest valley system within SQ1 is a compound incised valley, containing two nested valleys, each of which consists of amalgamated fluvial sandstones in the lower part, grading upward into heterolithic tidal/tidal-fluvial facies, and finally capped by more fluvial facies. There is a change in fluvial style from meandering into braided across the boundary of these two valleys. These observations support the existing nonmarine sequence stratigraphy models.;Facies within the fluvial-deltaic complex are diverse, ranging from river-dominated to storm/wave-dominated. Sedimentological analysis within parasequence 6 recognized a clear along-strike facies transition from sandy shoreface in the north, into heterolithic river-dominated delta-front facies southeastward, and into wave/storm-reworked facies further southeastward. Ichnogenera correspondingly show distinct along-strike changes from a robust and healthy archetypal Cruziana to Skolithos ichnofacies in the north into a suite characterized by horizontal, morphologically simple, facies-crossing structures of the suppressed Skolithos and Cruziana ichnofacies to the SE. Further southeastward, suites show higher abundance and diversity, and in some cases reflect the archetypal ichnofacies. The overall facies types and their distribution within the parasequence suggest delta asymmetry, with net longshore transport from north to south. However, unlike the recent delta asymmetry models, paralic, lagoonal, and bay-fill facies are largely absent in the studied asymmetric delta. This presumably reflects lack of paralic accommodation, because of negative shoreline trajectory, as well as post-depositional erosion during subsequent transgression.;A large amount of integrated sedimentological and ichnological data shows that the 100-160 m thick complex consists of 6 sequences, 18 parasequence sets, and 43 parasequences. Without this extensive data control, this stratal complexity could not be resolved, resulting in huge correlations uncertainties.