Transcripción del resumen del autor. Carolina Gomez-Veroiza received an M.S. degree in geology from Universidad de Chile in 2003 and a Ph.D. from the Jackson School of Geosciences, University of Texas at Austin in 2009. Her Ph.D. research work included source-to-sink characterization of a clastic wedge at different scales, especially in the fluvial to marine transition. She currently works as an exploration geologist for the Chilean state oil and gas company Enap Sipetrol. Ron Steel is a professor and a Davis Chair at the University of Texas at Austin and a Sixth-Century Chair at the University of Aberdeen, Scotland. He was previously a professor at the universities of Wyoming and Bergen and worked as a scientist and manager at Norsk Hydro, Bergen and Oslo. His interests are in dynamic stratigraphy and sedimentology, with current focus on shelf-margin growth, sedimentation and tectonics, and tidal bars and dunes. A 300-km (186-mi) transect was reconstructed across the 500-m (1640-ft)-thick, 3-m.y. duration Iles clastic wedge in southern Wyoming and northern Colorado using well logs and stratigraphic columns. This wedge developed into the middle–late Campanian-aged Western Interior seaway by progradation from the active Sevier fold and thrust belt and adjacent uplifted areas. The wedge thickens basinward because late-stage, widespread uplift of the fold belt caused multiple unconformities across the proximal (former foredeep) reaches of the foreland basin. Transect analysis allows the wedge and its component sequences to be better understood and permits a two-dimensional characterization of the sand and mud distribution. The Iles wedge exhibits 11 low-gradient, regressive-transgressive, high-frequency sequences that were correlated across several hundred kilometers. Sediment partitioning analysis along the transect shows the following. (1) Within the regressive limb of the Iles wedge, the component higher order regressive compartments tend to thicken into the medial reaches of the wedge, whereas transgressive compartments thicken landward. This geometry is driven by preferential erosion in proximal areas during regression, bypassing much sediment to the marine shorelines, and transgressive backfilling into proximal areas previously eroded more deeply. (2) The greatest concentration of sands tends to be located in the proximal fluvial and estuarine facies of the transgressive compartments and within the medial (shoreline) deltaic facies of the regressive compartments. (3) As the high-frequency sequences develop, the effectiveness of basinward sand partitioning reaches a maximum value near the peak regression level of the wedge, apparently reflecting stronger erosion and sediment bypass during these times.

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