Submarine canyons of Santa Monica Bay, Southern California: Variability in morphology and sedimentary processes

Abstract High-resolution autonomous underwater vehicle (AUV)-based multibeam bathymetry and chirp sub-bottom profiles were used to map the axial channels of Santa Monica and Redondo Canyon-Channel Systems, offshore southern California. The new bathymetry reveals the seafloor morphology at 1-meter grid resolution, whereas sub-bottom chirp and regional multichannel seismic reflection (MCS) profiles allow characterizing the shallow and deep sedimentary record, respectively. Even though these two submarine canyons have coexisted under the same regional controls (i.e., tectonics and sea-level changes), they have evolved distinctly over time. Turbidity current activity along the Redondo Canyon-Channel System as a result of canyon-head incision to the present-day shoreline resulted in a different geomorphology compared to the abandoned Santa Monica Canyon. The Redondo Canyon and channel system presents a number of morphologies, namely terraces, gullies, arcuate scarps, distinctive canyon-floor scarps (DCFS), crescent-shaped bedforms (CSBs) and scours. Their geneses, especially the CSBs along the Redondo axial channel, are the result of the morphodynamic interaction between turbidity flows and the seafloor. We infer that sediment gravity flows are the dominant process shaping the Redondo Canyon and channel system and transporting material to the San Pedro Basin. In contrast, the Santa Monica Canyon displays a smooth, flat-bottomed and partially in-filled axial channel, which lacks axial incision and large sediment bedforms indicating infilling at present. We interpret the large scours on the flanks of Santa Monica Canyon and the sediment waves on the Redondo Fan, respectively, as bedforms produced by repeated cyclic steps in turbidity currents which alternated between net erosional and net depositional.

[1]  M. Canals,et al.  Integrated study of Mediterranean deep canyons: Novel results and future challenges , 2013 .

[2]  C. Murray,et al.  Acoustic profiles and images of the Palos Verdes margin: implications concerning deposition from the White's Point outfall , 2002 .

[3]  D. Piper,et al.  Sea‐level and tectonic control of middle to late Pleistocene turbidite systems in Santa Monica Basin, offshore California , 2006 .

[4]  P. Barnes,et al.  Morphostructure and evolution of submarine canyons across an active margin: Cook Strait sector of the Hikurangi Margin, New Zealand , 2009 .

[5]  N. Mitchell.  Morphologies of knickpoints in submarine canyons , 2006 .

[6]  G. Dunhill,et al.  Cruise report for 01-99-SC: southern California earthquake hazards project , 1999 .

[7]  P. Dayton,et al.  Macrofaunal communities within and adjacent to a detritus-rich submarine canyon system , 1998 .

[8]  J. Winterwerp,et al.  Hyperconcentrated Sand‐Water Mixture Flows over Erodible Bed , 1992 .

[9]  N. Mitchell.  Interpreting long-profiles of canyons in the USA Atlantic continental slope , 2005 .

[10]  D. Bottjer,et al.  Holocene sea-level curves for santa monica shelf, california continental borderland. , 1981, Science.

[11]  M. Barton,et al.  Architecture and evolution of upper fan channel-belts on the Niger Delta slope and in the Arabian Sea , 2003 .

[12]  M. Lamb,et al.  Do hyperpycnal-flow deposits record river-flood dynamics? , 2009 .

[13]  D. Caress,et al.  High-resolution bathymetry of the axial channels within Monterey and Soquel submarine canyons, offshore central California , 2011 .

[14]  B. Dennielou,et al.  A walk down the Cap de Creus canyon, Northwestern Mediterranean Sea: Recent processes inferred from morphology and sediment bedforms , 2007 .

[15]  J. H. Berg,et al.  A comparative study of sediment waves and cyclic steps based on geometries, internal structures and numerical modeling , 2011 .

[16]  Tao Sun,et al.  Transportational cyclic steps created by flow over an erodible bed. Part 2. Theory and numerical simulation , 2005 .

[17]  Svetlana Kostic,et al.  Submarine channel initiation, filling and maintenance from sea‐floor geomorphology and morphodynamic modelling of cyclic steps , 2014 .

[18]  P. Harris,et al.  Global distribution of large submarine canyons: Geomorphic differences between active and passive continental margins , 2011 .

[19]  D. Cacchione,et al.  The Shaping of Continental Slopes by Internal Tides , 2002, Science.

[20]  Octavio E. Sequeiros,et al.  Cyclic steps: A phenomenon of supercritical shallow flow from the high mountains to the bottom of the ocean , 2010 .

[21]  J. Laberg,et al.  Morphology and morphogenesis of a high-latitude canyon; the Andøya Canyon, Norwegian Sea , 2007 .

[22]  V. Ivanov,et al.  Cascades of dense water around the world ocean [review article] , 2004 .

[23]  B. Klein,et al.  Morphology and architecture of the present canyon and channel system of the Zaire deep-sea fan , 2002 .

[24]  D. Caress,et al.  Fine‐scale relief related to Late Holocene channel shifting within the floor of the upper Redondo Fan, offshore Southern California , 2009 .

[25]  P. Iampietro,et al.  Semiannual patterns of erosion and deposition in upper Monterey Canyon from serial multibeam bathymetry , 2005 .

[26]  B. E. Haner.  Morphology and Sediments of Redondo Submarine Fan, Southern California , 1971 .

[27]  W. Ryan,et al.  Submarine canyon initiation by downslope-eroding sediment flows: Evidence in late Cenozoic strata on the New Jersey continental slope , 1994 .

[28]  Judith L. Connor,et al.  Debris in the deep: Using a 22-year video annotation database to survey marine litter in Monterey Canyon, central California, USA , 2013 .

[29]  K. Sieh,et al.  Prospects for Larger or More Frequent Earthquakes in the Los Angeles Metropolitan Region , 1995, Science.

[30]  G. Parker,et al.  Transportational cyclic steps created by flow over an erodible bed. Part 1. Experiments , 2005 .

[31]  Victoria Lynn Packard,et al.  Earthquake Hazards Program , 2013 .

[32]  P. Iampietro,et al.  Twenty-nine months of geomorphic change in upper Monterey Canyon (2002-2005) , 2007 .

[33]  D. Montgomery,et al.  Where do channels begin? , 1988, Nature.

[34]  R. Wynn,et al.  Geomorphology and sedimentary features in the Central Portuguese submarine canyons, western Iberian margin , 2009 .

[35]  H. G. Greene,et al.  Caught in the act: the 20 December 2001 gravity flow event in Monterey Canyon , 2002 .

[36]  G. Parker,et al.  The response of turbidity currents to a canyon–fan transition: internal hydraulic jumps and depositional signatures , 2006 .

[37]  D. Scholl,et al.  Geology and resource potential of the continental margin of Western North America and Adjacent Ocean Basins: Beaufort Sea to Baja California. Circum-Pacific council for energy and mineral resources earth science series, Volume 6 , 1987 .

[38]  H. Thomas,et al.  Axial Channel Morphology Fill and Movement Within Submarine Canyons off California , 2008 .

[39]  J. Peakall,et al.  A Process Model for the Evolution, Morphology, and Architecture of Sinuous Submarine Channels , 2000 .

[40]  L. Donelson Wright,et al.  Transport of particles across continental shelves , 1994 .

[41]  M. Gaudin,et al.  Axial incision : The key to understand submarine canyon evolution (in the western Gulf of Lion) , 2005 .

[42]  C. Paull,et al.  Sandwave migration in Monterey Submarine Canyon, Central California , 2008 .

[43]  F. P. Shepard.  Submarine Canyons: Multiple Causes and Long-Time Persistence , 1981 .

[44]  Octavio E. Sequeiros,et al.  Experiments on Wedge-Shaped Deep Sea Sedimentary Deposits in Minibasins and/or on Channel Levees Emplaced by Turbidity Currents. Part II. Morphodynamic Evolution of the Wedge and of the Associated Bedforms , 2009 .

[45]  J. Suppe,et al.  Late Cenozoic tectonic evolution of the Los Angeles basin and inner California borderland: A model for core complex-like crustal extension , 1993 .

[46]  R. Osborne,et al.  Relationships between sand input from rivers and the composition of sands from the beaches of Southern California , 1976 .

[47]  D. Piper,et al.  Sandy fans--from Amazon to Hueneme and beyond , 2001 .

[48]  B. Romans,et al.  Highstand fans in the California borderland: The overlooked deep-water depositional systems , 2007 .

[49]  H. Posamentier,et al.  Variability in form and growth of sediment waves on turbidite channel levees , 2002 .

[50]  J. Milliman,et al.  Hyperpycnal sediment discharge from semiarid southern California rivers: Implications for coastal sediment budgets , 2003 .

[51]  D. Inman,et al.  Currents in Submarine Canyons: An Air-Sea-Land Interaction , 1976 .

[52]  Albert Palanques,et al.  Flushing submarine canyons , 2006, Nature.

[53]  A. Micallef,et al.  Significance of the fine drainage pattern for submarine canyon evolution: The Foix Canyon System, Northwestern Mediterranean Sea , 2013 .

[54]  D. Gorsline,et al.  Processes and morphology of continental slope between Santa Monica and Dume Submarine Canyons, southern California , 1978 .

[55]  M. Kamerling,et al.  Restraining segments and reactivation of the Santa Monica–Dume–Malibu Coast fault system, offshore Los Angeles, California , 2006 .

[56]  Homa J. Lee,et al.  Earth Science in the Urban Ocean: The Southern California Continental Borderland , 2009 .

[57]  J. Vedder.  Regional Geology and Petroleum Potential of the Southern California Borderland , 1987 .

[58]  J. Syvitski,et al.  Turbidity Currents Generated at River Mouths during Exceptional Discharges to the World Oceans , 1995, The Journal of Geology.

[59]  Svetlana Kostic,et al.  Modeling of submarine cyclic steps: Controls on their formation, migration, and architecture , 2011 .

[60]  C. Paull,et al.  A comparison of megafaunal communities in five submarine canyons off Southern California, USA , 2014 .

[61]  D. García-Castellanos,et al.  Survival of a submarine canyon during long-term outbuilding of a continental margin , 2012 .

[62]  W. Normark.  Growth Patterns of Deep-Sea Fans , 1970 .

[63]  L. Pratson,et al.  A model for the long-profile shape of submarine canyons , 2009 .

[64]  B. Romans,et al.  Submarine canyon and fan systems of the California Continental Borderland , 2009 .

[65]  T. Rockwell,et al.  Style and rate of Holocene slip, Palos Verdes fault, southern , 1996 .

[66]  Russell B. Wynn,et al.  Classification and characterisation of deep-water sediment waves , 2002 .

[67]  A. Fildani,et al.  Channel formation by flow stripping: large‐scale scour features along the Monterey East Channel and their relation to sediment waves , 2006 .

[68]  T. McHargue,et al.  The natural range of submarine canyon-and-channel longitudinal profiles , 2011 .

[69]  K. Emery,et al.  Submarine Topography off the California Coast: Canyons and Tectonic Interpretation , 1942 .

[70]  C. Paull,et al.  Slip rate on the San Diego trough fault zone, inner California Borderland, and the 1986 Oceanside earthquake swarm revisited , 2012 .

[71]  P. Carlson,et al.  Giant submarine canyons: is size any clue to their importance in the rock record? , 2003 .

[72]  D. Stow,et al.  Deep-water sedimentary systems: New models for the 21st century , 2000 .

[73]  L. Pratson,et al.  Transient erosion in the Valencia Trough turbidite systems, NW Mediterranean Basin , 2011 .

[74]  B. Castelle,et al.  High-resolution morphobathymetric analysis and evolution of Capbreton submarine canyon head (Southeast Bay of Biscay—French Atlantic Coast) over the last decade using descriptive and numerical modeling , 2014 .

[75]  T. Nardin.  Late Quaternary Depositional Systems and Sea Level Change--Santa Monica and San Pedro Basins, California Continental Borderland , 1983 .

[76]  L. Pinheiro,et al.  Crescent-shaped morphotectonic features in the Gulf of Cadiz (offshore SW Iberia) , 2010 .

[77]  D. Caress,et al.  Origins of large crescent-shaped bedforms within the axial channel of Monterey Canyon, offshore California , 2010 .

[78]  Normark,et al.  Sea level controls on the textural characteristics and depositional architecture of the Hueneme and associated submarine fan systems, Santa Monica Basin, California , 1998 .

[79]  J. Baek,et al.  Trace organic contaminants and their sources in surface sediments of Santa Monica Bay, California, USA. , 2010, Marine environmental research.

[80]  J. Covault,et al.  Submarine fans at all sea-level stands: Tectono-morphologic and climatic controls on terrigenous sediment delivery to the deep sea , 2010 .

[81]  Norihiro Izumi,et al.  Purely erosional cyclic and solitary steps created by flow over a cohesive bed , 2000, Journal of Fluid Mechanics.

[82]  B. Savoye,et al.  Quaternary development of migrating sediment waves in the Var deep-sea fan: distribution, growth pattern, and implication for levee evolution , 2000 .

[83]  Peter Dartnell,et al.  Geomorphology, acoustic backscatter, and processes in Santa Monica Bay from multibeam mapping. , 2003, Marine environmental research.

[84]  D. Piper,et al.  Turbidite Depositional Patterns and Flow Characteristics, Navy Submarine Fan, California Borderland , 1983 .

[85]  R. Hagen,et al.  Morphology of a large meandering submarine canyon system on the Peru-Chile forearc , 1994 .

[86]  P. Kuus,et al.  Temporal progression and spatial extent of mass wasting events on the Squamish prodelta slope , 2012 .

[87]  S. McPhail,et al.  New insights into the morphology, fill, and remarkable longevity (>0.2 m.y.) of modern deep-water erosional scours along the northeast Atlantic margin , 2011 .

[88]  D. Caress,et al.  Anatomy of the La Jolla Submarine Canyon system; offshore southern California , 2013 .

[89]  C. Nittrouer,et al.  Evidence for superelevation, channel incision, and formation of cyclic steps by turbidity currents in Eel Canyon, California , 2008 .

[90]  Dale N. Chayes,et al.  Improved processing of Hydrosweep DS multibeam data on the R/V Maurice Ewing , 1996 .

[91]  Hans Thomas,et al.  High-Resolution Multibeam, Sidescan, and Subbottom Surveys Using the MBARI AUV D. Allan B , 2008 .