Many organic-rich mudstone deposits have been interpreted in the context of water column stratification. Here, Könitzer et al. examine temporal variations of, and controls on, the abundance and type of organic matter in late Paleozoic organic-rich mudstones from an epicontinental marine basin. Detailed microtextural analysis with data on total organic carbon (TOC) and bulk carbon isotope composition of organic material (δ13Corg) suggest alternative mechanisms for deposition of Lower Carboniferous succession. The data are interpreted to represent changes in productivity, variations in the delivery of siliciclastics and terrestrial organic matter. The abundance of organic matter stored in these extensive marine basins influenced the carbon cycle during this icehouse period in Earth history and the suitability of Late Mississippian mudstone successions of the U.K. as prospects for shale gas.
Depositional controls on mudstone lithofacies in abasinal setting: implications for the delivery of sedimentary organic matter by Sven F. Könitzer, Sarah J. Davies, Michael H. Stephenson, and Melanie J. Leng