Expedition 356 summary

Gallagher, S.J.; Fulthorpe, C.S.; Bogus, KA; Scientists, Expedition

doi:10.14379/iodp.proc.356.101.2017

Cited by 18 publications

(46 citation statements)

References 112 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At Site U1464, the deepening and the shift of the lithofacies happens much more abruptly at~6 Ma with the transition from shallow marine carbonates and evaporates (Unit IV), to the deeper mudstone facies (Unit III 144.3-317.46 m CCSF-A) paired with a sharp increase in PF% from <10% to >90% (Figures 2 and 5). In general, Site U1464 is interpreted as a deeper basin environment, with its estimated paleodepth always greater (upper bathyal) than that of U1463 (middle-outer shelf) during our study interval (Gallagher et al, 2017;Gurnis et al, 2020; Figure 2).…”

Section: 1029/2019pa003780mentioning

confidence: 75%

See 1 more Smart Citation

The Late Miocene to Early Pliocene “Humid Interval” on the NW Australian Shelf: Disentangling Climate Forcing From Regional Basin Evolution

Karatsolis

Vleeschouwer

Groeneveld

et al. 2020

Paleoceanog and Paleoclimatol

Self Cite

View full text Add to dashboard Cite

Pre-Quaternary paleoclimate studies in Australia mainly focus on terrestrial records from the southeastern part of the continent. IODP Expedition 356 drilled on the northwestern Australian shelf, yielding Miocene-Pleistocene paleoclimate records in an area where climate archives are scarce. Postexpedition research revealed a dry-to-humid transition across the latest Miocene and early Pliocene (start of the "Humid Interval"). However, the complex tectonic history of the area makes these interpretations challenging. In this study, we investigate late Miocene to early Pliocene sediment cores from two sites that are only 100 km apart but situated in two adjacent basins (Northern Carnarvon and Roebuck Basins). Combining lithofacies study, time series analysis of potassium content (K wt%), and calcareous nannofossil abundance counts (N/g), this work disentangles the complex interplay between basin evolution and climate change between 6.1 and 4 Ma. Overall, the investigated proxies show high correlation between both sites, except during 6.1-5.7 Ma. During this interval, Site U1463 records a gradual increase in K wt%, correlated with basin deepening, whereas Site U1464 records an abrupt rise in K wt% at~6 Ma. We explain this diachronicity by differential basin subsidence. The tectonic interplay with our paleorecords makes it difficult to pinpoint the exact onset of the "Humid Interval," but we conclude that K wt% and coccolith abundances at Site U1464 indicate that a fluvial deposition system was already established since at least 6 Ma. This age is consistent with data supporting a southward movement of the Intertropical Convergence Zone rain belt at~7 Ma. Previous work has revealed long-term and short-term fluctuations of arid and humid conditions during the Pleistocene and Pliocene, with a bias toward paleorecords from the southeastern part of the continent (

show abstract

Section: 1029/2019pa003780mentioning

confidence: 75%

“…An additional tie point was the marked decrease in small Reticulofenestra spp., a distinct biostratigraphic event observed at both sites (assigned an age of 4.51 Ma, based on the U1463 age model). (Gallagher et al, 2017). A description of the lithostratigraphic units can be found in Table S1.…”

Section: Astronomical Tuning and Time Series Analysismentioning

confidence: 99%

The Late Miocene to Early Pliocene “Humid Interval” on the NW Australian Shelf: Disentangling Climate Forcing From Regional Basin Evolution

Karatsolis

Vleeschouwer

Groeneveld

et al. 2020

Paleoceanog and Paleoclimatol

Self Cite

View full text Add to dashboard Cite

show abstract

“…(B) Plate tectonic motion of Australia since 50 million years ago in 10 million year intervals, with the path line for Site U1459 (Exp. 356) adapted from Gallagher et al (2017).…”

Section: Discussionmentioning

confidence: 99%

Finding Dry Spells in Ocean Sediments

Gallagher¹

2019

Oceanog

View full text Add to dashboard Cite

“…Carbonate and mudrock rock physics model, were derived from abundant core and wireline data acquired during the recent IODP Expedition 356 (Gallagher, et al, 2017). The expedition focussed on Neogene sediments at several sites in the NW Shelf of Australia but we believe the results should remain accurate for equivalent facies along much of the Westralian superbasin.…”

Section: Shallow Carbonate Rock Physicsmentioning

confidence: 99%

“…The holistic sampling approach employed by the IODP (Gallagher, et al, 2017) enabled different carbonate facies to be broken out with elastic properties measured to surface. Continuous coring enabled frequent sampling of porosity and therefore a near-continuous density profile could be built for each facies.…”

Section: Introductionmentioning

confidence: 99%

Geomechanical prestack depth migration of the Kraken 3D (Browse Basin, Australia)

Dunne¹,

Zengerer²,

Stein

et al. 2018

ASEG Extended Abstracts

View full text Add to dashboard Cite

SUMMARYConventional pre-stack depth migration applied to the broadband Kraken 3D Marine Seismic Survey was unable to fully resolve shortwavelength velocity anomalies below the sea floor causing obvious imaging problems and limiting depth conversion and amplitude interpretation. Improved imaging was achieved by initiating tomography using a velocity model built by combining geomechanics with rock physics appropriate for shallow carbonates and mudrocks.3D gravity modelling using high-resolution bathymetry and compaction trends constitutes a new approach for iteratively building a 3D geomechanical model. Effective stress is derived by applying Terzaghi's principle within an integration (along depth) involving the model bulk and fluid densities and the vertical component of gravity (all of which may vary spatially, using more refined models).Carbonate and mudrock rock physics models, believed to be appropriate for Neogene sediments along much of the NW Shelf of Australia were derived from abundant core and wireline data acquired during the recent IODP Expedition 356. These models provide the necessary link between effective stress and P-wave velocity with Backus averaging handling the "seismic scale" mixing of different lithologies expected in the Kraken 3D area.Kirchhoff prestack depth migration was revisited from archived preprocessed gathers using the geomechanical model combined with Common reflection angle gathers (CRAM) to initiate tomography. CRAM gathers were very effective in the presence of multiples and complex near surface topography to achieve a better update in tomography. Heavy smoothing of velocities was imposed where sequence stratigraphic interpretation suggests only distal mudstone facies. Tomography in shallower layers was then revisited to restore geologically plausible depth structures and deliver a clear improvement in imaging relative to previous processing efforts.

show abstract

Expedition 356 summary

Cited by 18 publications

References 112 publications

The Late Miocene to Early Pliocene “Humid Interval” on the NW Australian Shelf: Disentangling Climate Forcing From Regional Basin Evolution

The Late Miocene to Early Pliocene “Humid Interval” on the NW Australian Shelf: Disentangling Climate Forcing From Regional Basin Evolution

Finding Dry Spells in Ocean Sediments

Geomechanical prestack depth migration of the Kraken 3D (Browse Basin, Australia)

Contact Info

Product

Resources

About