Depositional Architecture of Glacigenic Regressive Deltas

Abstract

Dedicated Glaciations In this paper we will document the stratigraphic evolution, internal facies architecture and geomorphology of regressive glacigenic deltas, controlled by rapid high-amplitude base-level change. These systems are excellent field example to test the effect of high-amplitude base-level change on glacigenic delta systems, because subsidence, compaction, wave or tides did not play a major role. A large data set, including outcrop data, borehole data and high-resolution shear-wave seismic sections can resolve architectural elements in the range of metres and bridge the common gap between outcrop and standard industrial compression wave seismic data. The objective of this work is to provide a synthesis of the stratigraphic architecture of regressive deltas, giving new insights into the controls on delta building and erosion processes. The emphasis is placed on the sedimentary facies associations, the correlation of seismic facies with boreholes and outcrops and the analysis of the larger scale stacking pattern of architectural elements. A new depositional model summarizing facies features, depositional processes and architectures is proposed that may add to the sequence stratigraphic interpretation of steep glacigenic delta systems, controlled by rapid base-level change.