The problem of spatial–temporal complexity in defining past human impact in the terrestrial stratigraphic record is also apparent in the heavily populated northeastern USA. Previous research has documented increased sedimentation in lacustrine and alluvial DNA Damage inhibitor settings linked to prehistoric farming and forest clearance over 1000 years ago

(Stinchcomb et al., 2012). Research has also shown that the deposition alluvium due to early Euro-American mill dam production and the concomitant plowing of uplands is widespread, occurring throughout much of eastern USA river valleys (Walter and Merritts, 2008). Finally, widespread Mn-enrichment in soils of Pennsylvania has been linked with industrial-era inputs from steel and ferroalloy manufacturing, gasoline emissions, and coal combustion (Herndon et al., 2011). These three examples of human impact occurred in a variety of depositional and weathering environments, were likely widespread,

but patchy in spatial extent, and spanned various times during the past ∼1000 years. In order to address the spatial–temporal complexity of human impact on the stratigraphic record we propose an Anthropogenic Event stratigraphy, adapted from the International Union of Quaternary Science’s (INQUA) event stratigraphy approach (INQUA, 2012 and Seilacher, 1982). Event stratigraphy is defined as a stratigraphic trace of sediment, soil, or a surface that is relatively short-lived (instant to several thousand Apoptosis inhibitor years) and is mappable in its extent. We modified the event stratigraphy approach to include anthropogenic processes, i.e. Anthropogenic

Pregnenolone Event stratigraphy. The Anthropogenic Event stratigraphy approach was applied to a coal mining region because the occurrence and historic mining of coal beds are global in scale (Tewalt et al., 2010). This study determines the timing and extent of human impact on the landscape using an example from 18th to 20th century coal mining industry in the northeastern USA. This anthropogenic coal-mining event, here formally designated as the Mammoth Coal Event, is discussed in terms of impacts on the geomorphology of the region and implications for other depositional settings. When viewed in conjunction with other anthropogenic events, the Mammoth Coal Event will, in time, help to formulate a more comprehensive and meaningful correlation of human influence upon Earth surface processes. Geomorphic mapping, event stratigraphy, and archeological and historical research were used to document, correlate, and chronologically constrain widespread alluvial coal deposits and evidence of human impact throughout the Schuylkill and Lehigh River basins. Geomorphic maps were constructed using bare-Earth LiDAR and Natural Resources Conservation Service (NRCS) soil survey maps to determine the extent of previously recorded alluvial coal deposits, occurrence of abandon mines and mine dumps, and location of key archeological sites where coal alluvium was recorded.