Although that dastardly diagenesis plays a role, many of the same depositional factors that control sequence stratigraphy also influence the composition of sandy sediment within those sequences. Taking this concept as a starting point, Tentori and others unravel relationships between siliciclastic sediment composition (petrofacies) and sequence stratigraphic systems tracts of the Quaternary sedimentary succession of the Roman Basin. The results document different quartz/feldspar and quartz/lithic ratios, and textural changes, among systems tracts. These changes are interpreted to represent the influences of hydraulic sorting (by various processes among systems tracts) and post-depositional in situ weathering, and are linked to tectonics, volcanism, and relative changes in sea level. The data show how a sedimentary petrographic approach can be used to derive information on the stage evolution of a sedimentary succession through time. These results might be directly applicable to petroleum exploration and production in wave-dominated deltaic succession.
Sand compositional changes as a support for sequence-stratigraphic interpretation: the middle upper Pleistocene to Holocene deposits of the Roman Basin (Rome, Italy) by Daniel Tentori, Kathleen M. Marsaglia, and Salvatore Milli