Transient erosion in the Valencia Trough turbidite systems, NW Mediterranean Basin

Amblàs, David; Gerber, Thomas P.; Canals, Miquel; Pratson, Lincoln F.; Úrgeles, Roger; Lastras, Galderic; Calafat, Antoni

doi:10.1016/j.geomorph.2011.03.013

Cited by 30 publications

(23 citation statements)

References 54 publications

(81 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While the backstripped Pt2 long profi le clearly shows a sigmoidal (convex-concave) curvature, the modern Orpesa long profi le displays a positive (concave up) curvature (Fig. 3B) similar to all Valencia Trough turbidite system modern canyons along the EM (Amblas et al, 2011). Following the model of Gerber et al (2009), we interpret this change in long-profi le curvature as a change in the relative importance of background sedimentation, construed here as a mix of hemipelagic settling and deposition from weak shelf gravity fl ows that dissipate below wave base (sensu Parker, 2006).…”

Section: Long-term Canyon Constructionmentioning

confidence: 83%

“…The Orpesa Canyon is the southernmost modern tributary of the Valencia Trough turbidite systems. The concordance of the Orpesa Canyon long profi le with the modern Valencia Channel, the main conduit of the turbidite systems, suggests recent activity in the canyon (Amblas et al, 2011). Here we analyze its evolution from the mid-Pleistocene to the Holocene, a period of rapid high-amplitude sea-level fl uctuations and increased sedimentation along the EM (Nelson, 1990;Kertznus and Kneller, 2009).…”

Section: Geological Frameworkmentioning

confidence: 99%

See 1 more Smart Citation

Survival of a submarine canyon during long-term outbuilding of a continental margin

Amblàs¹,

Gerber²,

Mol³

et al. 2012

Geology

Self Cite

View full text Add to dashboard Cite

Net-depositional submarine canyons are common in continental slope strata, but how they survive and prograde on constructional margins is poorly understood. In this study we present fi eld evidence for the coevolution of a submarine canyon and the adjacent continental slope. Using a three-dimensional seismic data cube that images the Ebro margin (northwest Mediterranean), we identify a preserved canyon on a middle Pleistocene paleosurface and relate it directly to its expression on the present-day seafl oor. A subparallel stacking pattern of seismic refl ectors, similar to that seen between prograding clinoforms in intercanyon areas, is observed between the modern and paleocanyon thalwegs. The concavity of the modern long profi le differs from the convexconcave long profi le on the middle Pleistocene surface, suggesting a long-term change in canyon sedimentation. We interpret this change as a shift to a canyon dominated by turbidity currents from one strongly infl uenced by the pattern of sedimentation that built the open-slope canyon interfl uves. We fi nd support for our interpretation in previous studies of the Ebro margin.

show abstract

Section: Long-term Canyon Constructionmentioning

confidence: 83%

Section: Geological Frameworkmentioning

confidence: 99%

Survival of a submarine canyon during long-term outbuilding of a continental margin

Amblàs¹,

Gerber²,

Mol³

et al. 2012

Geology

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition to the knickpoints in the channel, the head of Hatteras Transverse Canyon and the side channel of upper Hatteras Transverse Canyon also appear to be eroding headward. The presence of knickpoints also could be an indication that the canyon channels are re-establishing their equilibrium profiles after a period of increased sedimentation (e.g., Amblas et al, 2011) after the last glacial lowstand, as first suggested by Embley and Jacobi (1986). Hatteras Canyon, a tributary channel to Hatteras Transverse Canyon, must be adjusting by erosion to a drop in the thalweg of Hatteras Transverse Canyon channel, the principal channel, because there is no suggestion of a step down at the confluence of the two channel floors.…”

Section: Discussionmentioning

confidence: 99%

“…In fact, transverse submarine canyons are so rare that the review of the global distribution and geomorphologies of submarine canyons by Harris and Whiteway (2011) does not mention one submarine canyon that strikes transverse to a margin. However, a few such canyons; e.g., Ameghino Transverse Canyon and Almirante Brown Transverse (sometimes referred to as the Patagonia Canyon) on the Argentine margin (Lonardi and Ewing, 1971;Hernández-Molina et al, 2009;Lastras et al, 2011) and Valencia Valley in the northwestern Mediterranean Basin (Palanques and Maldonado, 1985;Amblas et al, 2011), have been described in some detail. In all of these examples, including Hatteras Transverse Canyon on the eastern U.S. Atlantic continental margin (Fig.…”

Section: Introductionmentioning

confidence: 99%

Hatteras Transverse Canyon, Hatteras Outer Ridge and environs of the U.S. Atlantic margin: A view from multibeam bathymetry and backscatter

2016

View full text Add to dashboard Cite

Previously unknown features in Hatteras Transverse Canyon and environs were recently mapped during multibeam surveys of almost the entire eastern U.S. Atlantic continental margin. The newly identified features include (1) extensive landslide scarps on the walls of Hatteras Transverse and Hatteras Canyons, (2) an area of multiple landslide deposits that block lower Hatteras Transverse Canyon, (3) a large depositional feature down-canyon from the landslide deposits that rises 100 m above the uppermost Hatteras Fan and has buried the transition from the mouth of Hatteras Transverse Canyon to uppermost Hatteras Fan, (4) a zone of cyclic steps on upper Hatteras Fan that suggests supercritical turbidity currents performed a series of hydraulic jumps and formed large upstream-migrating bedforms, (5) several knickpoints in the channel thalwegs of both Hatteras Transverse Canyon and Hatteras Canyon, one 40 m high, that suggest both canyon channels are out of equilibrium and are in the process of readjusting, either to the channel blockage by the extensive landslide deposits or by a readjustments to increased sedimentation during the last eustatic lowstand, (6) a large area of outcrop on the lower margin between Pamlico and Hatteras Canyons that previously was interpreted as an area of slumps, blocky slide debris and mud waves, (7) headward erosion in the head region of Hatteras Transverse Canyon where it has intercepted the lowest reaches of Albemarle Canyon channel as well as headward erosion in a small side channel that has eroded into Hatteras Outer Ridge and (8) sections of bedforms on Hatteras Outer Ridge that are partially buried by sediment from Washington-Norfolk Canyon channel as well as by sediment transported from Hatteras Abyssal Plain. The newly discovered features add a new level of detail to understand the recent processes that have profoundly affected Hatteras Transverse Canyon, Hatteras Canyon and, to a lesser degree, Hatteras Outer Ridge.

show abstract

“…We do not think that this is the case. Our study area is relatively small (~500 km 2 ) and the continental slope is characterised by quasi-uniform slope gradient, structure, substrate and oceanographic conditions (Farrán and Maldonado, 1990;Field and Gardner, 1990; Font et al, 1990;Amblas et al, 2006Amblas et al, , 2011Amblas et al, , 2012Urgeles et al, 2011). The material being eroded is predominantly Plio-Quaternary shelf-margin deltaic and slope depositional units, whilst the control of extensional and thrust faults on the seafloor is more important further south.…”

Section: Accepted M Manuscriptmentioning

confidence: 99%

Space-for-time substitution and the evolution of a submarine canyon–channel system in a passive progradational margin

et al. 2014

Self Cite

View full text Add to dashboard Cite

Please cite this article as: Micallef, Aaron, Ribó, Marta, Canals, Miquel, Puig, Pere, Lastras, Galderic, Tubau, Xavier, Space-for-time substitution and the evolution of a submarine canyon-channel system in a passive progradational margin, Geomorphology (2014), doi: 10.1016/j.geomorph.2014.06.008 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT1 Manuscript submitted to Geomorphology:Space-for-time substitution and the evolution of a submarine canyon-channel system in a passive progradational margin. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT2 AbstractSpace-for-time substitution is a concept that has been widely applied, but not thoroughly tested in some fields of geomorphology. The objective of this study is to test whether the concept of space-for-time substitution is valid in reconstructing the evolution of a submarine canyonchannel system in a passive progradational margin. We use multibeam echosounder data and in situ measurements from the south Ebro Margin to analyse the morphology and morphometry of a sequence of submarine valleys ordered in terms of increasing valley thalweg length. The morphological model of submarine valley evolution that we can propose from this analysis is very similar to established models in the literature, which leads us to conclude that time can be substituted by space when reconstructing the evolution of submarine canyon and channel systems in the south Ebro Margin. By extracting morphometric information from the application of the space-for-time substitution model to our data, we identify a series of morphological patterns as a submarine canyon evolves in a passive progradational margin. These include the geometric similarity of canyon planform shape, an increase in canyon draining efficiency and in the influence of flank slope failures, and an evolution towards equilibrium between canyon form and imposed water and sediment load without net erosion or deposition taking place. We also observe that canyon elongation is higher downslope and that the canyon undergoes an early stage of rapid incision similar to the process of "erosion narrowing" reported in terrestrial rivers. We demonstrate that the conclusions of our study are not limited to submarine valleys in the south Ebro Margin but are applicable to other margins around the world. A C C E P T E D M A N U S C R I P TACCEPTED MANUSCRIPT 3 IntroductionGeoscientists are generally unable to fully observe landscape-forming processes because the time-scale of the observer and the time-scale of many geomorphic phenomena are very different.One approach to...

show abstract

Transient erosion in the Valencia Trough turbidite systems, NW Mediterranean Basin

Cited by 30 publications

References 54 publications

Survival of a submarine canyon during long-term outbuilding of a continental margin

Survival of a submarine canyon during long-term outbuilding of a continental margin

Hatteras Transverse Canyon, Hatteras Outer Ridge and environs of the U.S. Atlantic margin: A view from multibeam bathymetry and backscatter

Space-for-time substitution and the evolution of a submarine canyon–channel system in a passive progradational margin

Contact Info

Product

Resources

About