Evaluation of the relative roles of global versus local sedimentary controls on middle to late Pleistocene formation of continental margin strata, Canterbury Basin, New Zealand

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doi: 10.1111/sed.12181
Author(s): Villaseñor, Tania; Jaeger, John M.; Marsaglia, Kathleen M.; Browne, Greg H.
Author Affiliation(s): Primary:
University of Florida, Department of Geological Sciences, Gainesville, FL, United States
Other:
California State University, United States
Volume Title: Sedimentology
Source: Sedimentology, 62(4), p.1118-1148. Publisher: Wiley-Blackwell, Oxford, United Kingdom. ISSN: 0037-0746 CODEN: SEDIAT
Note: In English. 106 refs.; illus., incl. sects., 4 tables, sketch maps
Summary: Determining the relative influence of eustasy versus local sedimentary processes on strata formation is a fundamental challenge in the study of continental margin stratigraphy. In this paper, the relative contribution of these factors on continental margin evolution during the Middle to Late Pleistocene is evaluated using samples from Integrated Ocean Drilling Program Expedition 317. Core-logging, biostratigraphy and quantitative X-ray diffraction mineralogy are used to delineate continental shelf sedimentary systems. Major lithological unconformities bound stratigraphic sequences that contain recurring compositional patterns and that resemble other examples of middle to upper Pleistocene sequences. However, a preliminary chronology suggests that sequence boundary formation cannot be linked "one to one" with eustatic cycles and therefore these sequences can contain multiple ca 100 ka eustatic cycles. Smaller amplitude, higher frequency transitions in sediment composition are interpreted as stratigraphic sequences driven by more rapid perturbations in the interplay of accommodation and sediment supply; their stratigraphy is variable in time and across the shelf, suggesting a strong influence of local sedimentary forcing in their formation. Changes in sediment composition after the Middle Pleistocene Transition indicate that sediment transfer from onshore sources in the glaciated Southern Alps to the middle-shelf occurred over a single 100 ka glacio-eustatic cycle, with an additional 100 ka lag before the mineralogical signal was preserved on the outer-shelf. This phenomenon is coincident with rapid shelf progradation in this basin, suggesting a causal relation between across-shelf sediment transport and margin progradation. This is one of very few studies that provide insights at the core scale into the processes driving continental margin evolution during the middle to late Pleistocene. This work shows that compositional changes in mud-dominated successions can lead to a sequence stratigraphic interpretation and the identification of high-frequency sequences, which may not be possible using a conventional stratigraphic approach. Abstract Copyright (2014), International Association of Sedimentologists.
Year of Publication: 2015
Research Program: IODP Integrated Ocean Drilling Program
ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 24 Surficial Geology, Quaternary Geology; Canterbury Basin; Cenozoic; Clastic sediments; Continental margin; Cycles; Depositional environment; Expedition 317; Geophysical methods; Geophysical profiles; Geophysical surveys; IODP Site U1353; IODP Site U1354; Integrated Ocean Drilling Program; Leg 181; Marine environment; Middle Pleistocene; Mineral composition; ODP Site 1119; Ocean Drilling Program; Pacific Ocean; Pleistocene; Quaternary; Reflection methods; Sea-level changes; Sediments; Seismic methods; Seismic profiles; Shelf environment; South Pacific; Southwest Pacific; Surveys; Upper Pleistocene; West Pacific; X-ray diffraction data
Coordinates: S445700 S444600 E1720200 E1714000
Record ID: 2015084789
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom