Time-series analysis of turbidite sequence in the upper part of the Awa Group in the Boso Peninsula, central Japan.

Ishihara, Yoshiro; Miyata, Yasumitsu; Tokuhashi, Shuichi

doi:10.5575/geosoc.103.579

Cited by 15 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar bimodal distribution of turbidite bed thickness is apparent in other non-channelized (Sadler, 1982;Talling, 2001;Sylvester, 2007) or weakly-channelized (Ishihara et al, 1997) sequences. Two frequency modes occur, again separated by a deficit of thickness values between 20 and 40 cm.…”

Section: Origin Of Bimodality In Turbidite Sandstone Thicknesssupporting

confidence: 65%

New insight into the evolution of large‐volume turbidity currents: comparison of turbidite shape and previous modelling results

Talling¹,

Amy²,

Wynn

2007

Sedimentology

178

View full text Add to dashboard Cite

The Marnoso Arenacea Formation provides the most extensive correlation of individual flow deposits (beds) yet documented in an ancient turbidite system. These correlations provide unusually detailed constraints on bed shape, which is used to deduce flow evolution and assess the validity of numerical and laboratory models. Bed volumes have an approximately log‐normal frequency distribution; a small number of flows dominated sediment supply to this non‐channelized basin plain. Turbidite sandstone within small‐volume (<0·7 km3) beds thins downflow in an approximately exponential fashion. This shape is a property of spatially depletive flows, and has been reproduced by previous mathematical models and laboratory experiments. Sandstone intervals in larger‐volume (0·7–7 km3) beds have a broad thickness maximum in their proximal part. Grain‐size trends within this broad thickness maximum indicate spatially near‐uniform flow for distances of ∼30 km, although the flow was temporally unsteady. Previous mathematical models and laboratory experiments have not reproduced this type of deposit shape. This may be because models fail to simulate the way in which near bed sediment concentration tends towards a constant value (saturates) in powerful flows. Alternatively, the discrepancy may be the result of relatively high ratios of flow thickness and sediment settling velocity in submarine flows, together with very gradual changes in sea‐floor gradient. Intra‐bed erosion, temporally varying discharge, and reworking of suspension fallout as bedload could also help to explain the discrepancy in deposit shape. Most large‐volume beds contain an internal erosion surface underlain by inversely graded sandstone, recording waxing and waning flow. It has been inferred previously that these characteristics are diagnostic of turbidites generated by hyperpycnal flood discharge. These turbidites are too voluminous to have been formed by hyperpycnal flows, unless such flows are capable of eroding cubic kilometres of sea‐floor sediment. It is more likely that these flows originated from submarine slope failure. Two beds comprise multiple sandstone intervals separated only by turbidite mudstone. These features suggest that the submarine slope failures occurred as either a waxing and waning event, or in a number of stages.

show abstract

Section: Origin Of Bimodality In Turbidite Sandstone Thicknesssupporting

confidence: 65%

New insight into the evolution of large‐volume turbidity currents: comparison of turbidite shape and previous modelling results

Talling¹,

Amy²,

Wynn

2007

Sedimentology

178

View full text Add to dashboard Cite

show abstract

“…It may be that this sort of signal is characteristic of more distal settings already dominated by mudstones with higher carbonate content. Unfortunately the literature provides little basis for comparison, in that prior statistical studies of turbidites have focused on trends in bed thickness and grain size (e.g., Chen and Hiscott 1999;Ishihara et al 1997). Nevertheless, this relationship is a hypothesis that bears further testing.…”

Section: Discussionmentioning

confidence: 99%

Eustatic Signals in Deep-Marine Sedimentary Sequences Recovered at ODP Site 978, Alboran Basin, Western Mediterranean Sea

Marsaglia¹,

Fukusawa²,

Cornell³

et al. 2004

Journal of Sedimentary Research

View full text Add to dashboard Cite

A continuous section of Pliocene marine sediments was recovered at Ocean Drilling Program Site 978, located in the Alboran Sea between Spain and Morocco. Three Pliocene subunits have been defined at Site 978: the lowermost (Subunit IC, 129.2 m thick) is characterized by alternating beds of lighter, more calcareous, and darker, less calcareous, claystone with bioturbated upper and lower contacts (Type 1 cycles); the middle (Subunit IB, 67.1 m thick) is composed of relatively homogeneous nannofossil claystone; and the uppermost (Subunit IA, 211.6 m thick) contains abrupt-based darker, terrigenous layers interpreted as turbidites that are interstratified with lighter nannofossil claystone (Type 2 cycles). The rhythmically bedded light and dark layers in Subunit IC correlate with those in the Rosello Composite Section of Sicily, a global reference standard for the Pliocene time scale. These sedimentary cycles are products of variations in precession and resulting continental runoff. Missing cycles occur during eustatic highstands. The shift to more homogeneous sedimentation in Subunit IB is represented in similar-aged sequences throughout the Mediterranean which display evidence of submarine mass wasting. Mediterranean-wide slope degradation was likely a response to rapid sea-level change at approximately 3 Ma. This change in sedimentation style was accompanied by an upsection increase in sediment accumulation rates associated with turbidite influx in Subunit IA. Turbidite frequency throughout the Pliocene section can be linked to eustatic changes in sea level, with turbidite maxima corresponding with mid-sequence downlap surfaces and their associated condensed sections.

show abstract

“…Many studies have shown an approximately log-normal frequency distribution of the sandy component of turbidite thickness (Hiscott and Middleton, 1979;Beeden, 1983;Drummond and Wilkinson, 1996;Murray et al, 1996;Ishihara et al, 1997). In addition, a power-law trend has been suggested for the cumulative frequency curve of sand layer thickness (Rothman et al, 1994.…”

Section: Frequency Distribution Of Turbidite Thicknessmentioning

confidence: 95%

Sedimentary processes and origin of sediment gravity-flow deposits on the western Algerian margin during late Pleistocene and Holocene

Giresse

Pauc

Déverchère

2009

Marine and Petroleum Geology

View full text Add to dashboard Cite

Time-series analysis of turbidite sequence in the upper part of the Awa Group in the Boso Peninsula, central Japan.

Cited by 15 publications

References 0 publications

New insight into the evolution of large‐volume turbidity currents: comparison of turbidite shape and previous modelling results

New insight into the evolution of large‐volume turbidity currents: comparison of turbidite shape and previous modelling results

Eustatic Signals in Deep-Marine Sedimentary Sequences Recovered at ODP Site 978, Alboran Basin, Western Mediterranean Sea

Sedimentary processes and origin of sediment gravity-flow deposits on the western Algerian margin during late Pleistocene and Holocene

Contact Info

Product

Resources

About