Autogenic Sedimentation in Clastic Stratigraphy

Abstract

Internally generated, or autogenic, terrestrial and marine sediment-transport dynamics can produce depositional patterns similar to those associated with climatic, tectonic, or sea level changes. A central challenge in accurately interpreting the sedimentary archive is determining what scales and types of deposits reflect autogenic controls on sedimentation in different environments. Autogenic sediment-transport dynamics commonly result from intermittent sediment storage in transient landforms, which produces episodic, spatially discontinuous sedimentation across a basin. The transition from localized, variable sedimentation to even, basin-wide sedimentation marks the shift from stochastic landscape dynamics to deterministic deposition responding to the long-term balance between sediment supply and the creation of space to accommodate sediment. This threshold can be measured in a wide variety of stratigraphic successions and has important bearing on whether climatic, tectonic, or sea level signals can be recognized in physical sedimentary deposits.