Estimation of source area, river paleo-discharge, paleoslope, and sediment budgets of linked deep-time depositional systems and implications for hydrocarbon potential

The source-to-sink (S2S) concept is focused on quantification of the various components of siliciclastic sedimentary systems from initial source sediment production areas, through the dispersal system, to deposition within a number of potential ultimate sedimentary sinks, and has more recently been applied to deep-time stratigraphic systems. Sequence-stratigraphic analysis is a key first step that allows depositional systems to be correlated and mapped, within a time-stratigraphic framework, such that fluvial transport systems can be linked to down-dip shorelines, shelf and deep-water deposits and interpreted in the context of allogenic processes. More recently, attempts have been made to quantify catchment areas for ancient depositional systems, using scaling relationships of modern systems. This also helps predict the size of linked depositional systems, such as rivers, deltas and submarine fans, along the S2S tract. The maximum size of any given depositional system, such as a river, delta, or submarine fan, is significantly controlled by the area, relief, and climate regime of the source area, which in turn may link to the plate tectonic and paleogeographic setting. Classic provenance studies, and more recent use of detrital geochronology, including zircons, provide critical information about source areas, and place limits on catchment area. Provenance studies, especially when linked to thermochronometry also provide key information about rates of exhumation of source areas and the link to the tectonic setting. In this paper the techniques for estimation of water and sediment paleodischarge and paleo-drainage area are outlined, and sediment budgets are calculated for a number of Mesozoic systems, primarily from western North America. The relevance for hydrocarbon exploration and production is discussed for each example. In Mesozoic Western Interior basins of North America, extensive outcrop and subsurface data allow the largest trunk rivers to be identified, typically within incised valleys. Thickness, grain size, and sedimentary structures can be used to infer slope and flow velocities, and using width estimations, water and sediment paleodischarge can be calculated. River paleoslope can also be independently measured from stratigraphic-geometric considerations and used to assess paleo-river flow. Paleodischarge in turn is used to estimate the size of the catchment source area. Paleodischarge of rivers can also be estimated independently by integrating