Dataset Identification:
Resource Abstract:
- description: This part of SIM 3281 presents data for the geologic and geomorphic map (see sheet 10, SIM 3281) of the Offshore
of Santa Barbara map area, California. The vector data file is included in "Geology_OffshoreSantaBarbara.zip," which
is accessible from http://pubs.usgs.gov/ds/781/OffshoreSantaBarbara/data_catalog_OffshoreSantaBarbara.html. The offshore part
of the map area largely consists of a relatively shallow (less than 75 m deep), gently offshore-dipping (less than 1 degree)
shelf underlain by sediments derived primarily from relatively small coastal watersheds that drain the Santa Ynez Mountains.
Shelf deposits are primarily sand (unit Qms) at water depths less than about 35 to 50 m and, at depths greater than about
35 to 50 m, are the more fine-grained sediments (very fine sand, silt, and clay) of unit Qmsf. The boundary between units
Qms and Qmsf is based on observations and extrapolation from sediment sampling (see, for example, Reid and others, 2006) and
camera ground-truth surveying (see sheet 6). It is important to note that the boundary between units Qms and Qmsf should be
considered transitional and approximate and is expected to shift as a result of seasonal- to annual- to decadal-scale cycles
in wave climate, sediment supply, and sediment transport. Coarser grained deposits (coarse sand to boulders) of unit Qmsc,
which are recognized on the basis of their high backscatter and, in some cases, their moderate seafloor relief (sheets 1,
2, 3), are found most prominently in a large (about 0.75 km2) lobe that is present from about 1,800 to 3,600 m offshore of
the mouth of Arroyo Burro, in water depths of about 36 to 65 m. The lobe is inferred to consist of coarse-grained sediment
(coarse sand to boulders) that is resistant to erosion. Although these coarse-grained deposits almost certainly are derived
from Arroyo Burro, the lobe could represent either the underflow deposits of late Holocene floods or a relict geomorphologic
feature, having been deposited in shallower marine deltaic (or even alluvial?) environments at lower sea levels in the latest
Pleistocene and early Holocene. Unit Qmsc also is present in shallower water (depths of about 10 to 20 m), most notably in
a small area (approximately 0.09 km2) that extends offshore from Montecito Creek, in the eastern part of the map area. The
presence of coarser grained sediment (coarse sand and possibly gravel) also is inferred in shallower water (depths of 10 to
20 m) offshore from Arroyo Burro, but these deposits are mapped as unit Qmss because they are found within arcuate scour depressions
that have been referred to as "rippled scour depressions" (see, for example, Cacchione and others, 1984; Phillips,
2007) or "sorted bedforms" (see, for example, Murray and Thieler, 2004; Goff and others, 2005; Trembanis and Hume,
2011). Although the general area in which Qmss scour depressions are found is not likely to change substantially, the boundaries
of the unit(s), as well as the locations of individual depressions and their intervening flat sand sheets, likely are ephemeral,
changing during significant storm events. Hydrocarbon-seep-induced topography, which is present most prominently along the
axis of anticlines, includes many features (described by Keller and others, 2007) along the trend of the Mid-Channel Anticline,
about 10 km south of the map area in the Santa Barbara Channel. Geologic map units associated with hydrocarbon emissions in
the map area include grouped to solitary pockmarks (unit Qmp) and asphalt (tar) deposits (unit Qas), as well as areas of undifferentiated
hydrocarbon-related features (unit Qhfu) that probably include a mix of mounds, mud volcanoes, pockmarks, carbonate mats,
and other constructional and erosional "seabed forms" (see Keller and others, 2007), all of which are superimposed
on consolidated, undivided Miocene and Pliocene bedrock (unit Tbu). Offshore bedrock exposures are assigned to the Miocene
Monterey Formation (unit Tm) and to the undivided Miocene and Pliocene bedrock unit (Tbu), primarily on the basis of extrapolation
from the onland geologic mapping of Minor and others (2009), as well as the geologic cross sections of Redin (2005). These
cross sections, which are constrained by industry seismic-reflection data and petroleum well logs, suggest that a considerable
part of the undivided bedrock unit may belong to the Pliocene and Pleistocene Pico Formation. Bedrock is, in some places,
overlain by a thin (less than 1 m?) veneer of sediment, recognized on the basis of high backscatter, flat relief, continuity
with moderate- to high-relief bedrock outcrops, and (in some cases) high-resolution seismic-reflection data; these areas,
which are mapped as composite units Qms/Tbu or Qms/Tm, are interpreted as ephemeral sediment layers that may or may not be
continuously present, depending on storms, seasonal and (or) annual patterns of sediment movement, or longer term climate
cycles. The Santa Barbara Channel region, including the map area, has a long history of petroleum production (Barnum, 1998).
The Monterey Formation is the primary petroleum-source rock in the Santa Barbara Channel, and the Pico Formation is one of
the primary petroleum reservoirs. The bedrock units typically are exposed in structural highs that include uplifts associated
with the partly blind(?), south-dipping Rincon Creek Fault Zone and the outer shelf anticlinal uplift that developed above
the south strand of the Red Mountain Fault in the southwestern part of the map area. The Offshore of Santa Barbara map area
is in the Ventura Basin, in the southern part of the Western Transverse Ranges geologic province, which is north of the California
Continental Borderland (Fisher and others, 2009). This province has undergone significant north-south compression since the
Miocene, and recent GPS data suggest north-south shortening of about 6 mm/yr (Larson and Webb, 1992). The active, east-west-striking
Red Mountain and Rincon Creek Faults and their related folds are some of the structures on which this shortening occurs. This
fault system, in aggregate, extends for about 100 km through the Ventura and Santa Barbara Basins and represents an important
earthquake hazard (see, for example, Fisher and others, 2009). Very high uplift rates of onland marine terraces from More
Mesa (2.2 mm/yr), in the western part of the map area, to Summerland (0.7 mm/yr), a few kilometers east of the map area, are
further indication of rapid shortening in this region (Keller and Gurrola, 2000). References Cited: Barnum, H.P., 1998, Redevelopment
of the western portion of the Rincon offshore oil field, Ventura, California, in Kunitomi, D.S., Hopps, T.E., and Galloway,
J.M., eds., Structure and petroleum geology, Santa Barbara Channel, California: American Association of Petroleum Geologists,
Pacific Section, and Coast Geological Society, Miscellaneous Publication 46, p. 201-215. Cacchione, D.A., Drake, D.E., Grant,
W.D., and Tate, G.B., 1984, Rippled scour depressions of the inner continental shelf off central California: Journal of Sedimentary
Petrology, v. 54, p. 1,280-1,291. Dibblee, T.W., Jr., 1986a, Geologic map of the Carpinteria quadrangle, Santa Barbara County,
California: Santa Barbara, Calif., Dibblee Geological Foundation Map DF-04, scale 1:24,000. Dibblee, T.W., Jr., 1986b, Geologic
map of the Santa Barbara quadrangle, Santa Barbara County, California: Santa Barbara, Calif., Dibblee Geological Foundation
Map DF-06, scale 1:24,000. Fisher, M.A., Sorlien, C.C., and Sliter, R.W., 2009, Potential earthquake faults offshore southern
California from the eastern Santa Barbara channel to Dana Point, in Lee, H.J., and Normark, W.R., eds., Earth science in the
urban ocean--The Southern California Continental Borderland: Geological Society of America Special Paper 454, p. 271-290.
Goff, J.A., Mayer, L.A., Traykovski, P., Buynevich, I., Wilkens, R., Raymond, R., Glang, G., Evans, R.L., Olson, H., and Jenkins,
C., 2005, Detailed investigations of sorted bedforms or "rippled scour depressions," within the Martha's Vineyard
Coastal Observatory, Massachusetts: Continental Shelf Research, v. 25, p. 461-484. Keller, E.A., Duffy, M., Kennett, J.P.,
and Hill, T., 2007, Tectonic geomorphology and hydrocarbon potential of the Mid-Channel anticline, Santa Barbara Basin, California:
Geomorphology, v. 89, p. 274-286. Keller, E.A., and Gurrola, L.D., 2000, Final report, July, 2000--Earthquake hazard of the
Santa Barbara fold belt, California: NEHRP Award #99HQGR0081, SCEC Award #572726, 78 p., available at http://www.scec.org/research/98research/98gurrolakeller.pdf.
Larson, K.M., and Webb, F.H., 1992, Deformation in the Santa Barbara Channel from GPS measurements 1987-1991: Geophysical
News Letters, v. 19, p. 1,491-1,494. Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A., and Brandt, T.R.,
2009, Geologic map of the Santa Barbara coastal plain area, Santa Barbara County, California: U.S. Geological Survey Scientific
Investigations Map 3001, scale 1:25,000, 1 sheet, pamphlet 38 p., available at http://pubs.usgs.gov/sim/3001/. Murray, B.,
and Thieler, E.R., 2004, A new hypothesis and exploratory model for the formation of large-scale inner-shelf sediment sorting
and "rippled scour depressions": Continental Shelf Research, v. 24, no. 3, p. 295-315. Phillips, E., 2007, Exploring
rippled scour depressions offshore Huntington Beach, CA: Santa Cruz, University of California, M.S. thesis, 58 p. Redin, T.,
2005, Santa Barbara Channel structure and correlation sections--Correlation Section no. 34A, Summerland area, Santa Ynez Mountains,
across the east central Santa Barbara Channel to the China Bay area, Santa Cruz Island: American Association of Petroleum
Geologists, Pacific Section, Publication CS 34A, 1 sheet. Reid, J.A., Reid, J.M., Jenkins, C.J., Zimmerman, M., Williams,
S.J., and Field, M.E., 2006, usSEABED--Pacific Coast (California, Oregon, Washington) offshore surficial-sediment data release:
U.S. Geological Survey Data Series 182, available at http://pubs.usgs.gov/ds/2006/182/. Trembanis, A.C., and Hume, T.M., 2011,
Sorted bedforms on the inner shelf off northeastern New Zealand--Spatiotemporal relationships and potential paleo-environmental
implications: Geo-Marine Letters, v. 31, p. 203-214. Weber, K.M., List, J.H., and Morgan, K.L., 2005, An operational Mean
High Water datum for determination of shoreline position from topographic lidar data: U.S. Geological Survey Open-File Report
2005-1027, available at http://pubs.usgs.gov/of/2005/1027/.; abstract: This part of SIM 3281 presents data for the geologic
and geomorphic map (see sheet 10, SIM 3281) of the Offshore of Santa Barbara map area, California. The vector data file is
included in "Geology_OffshoreSantaBarbara.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshoreSantaBarbara/data_catalog_OffshoreSantaBarbara.html.
The offshore part of the map area largely consists of a relatively shallow (less than 75 m deep), gently offshore-dipping
(less than 1 degree) shelf underlain by sediments derived primarily from relatively small coastal watersheds that drain the
Santa Ynez Mountains. Shelf deposits are primarily sand (unit Qms) at water depths less than about 35 to 50 m and, at depths
greater than about 35 to 50 m, are the more fine-grained sediments (very fine sand, silt, and clay) of unit Qmsf. The boundary
between units Qms and Qmsf is based on observations and extrapolation from sediment sampling (see, for example, Reid and others,
2006) and camera ground-truth surveying (see sheet 6). It is important to note that the boundary between units Qms and Qmsf
should be considered transitional and approximate and is expected to shift as a result of seasonal- to annual- to decadal-scale
cycles in wave climate, sediment supply, and sediment transport. Coarser grained deposits (coarse sand to boulders) of unit
Qmsc, which are recognized on the basis of their high backscatter and, in some cases, their moderate seafloor relief (sheets
1, 2, 3), are found most prominently in a large (about 0.75 km2) lobe that is present from about 1,800 to 3,600 m offshore
of the mouth of Arroyo Burro, in water depths of about 36 to 65 m. The lobe is inferred to consist of coarse-grained sediment
(coarse sand to boulders) that is resistant to erosion. Although these coarse-grained deposits almost certainly are derived
from Arroyo Burro, the lobe could represent either the underflow deposits of late Holocene floods or a relict geomorphologic
feature, having been deposited in shallower marine deltaic (or even alluvial?) environments at lower sea levels in the latest
Pleistocene and early Holocene. Unit Qmsc also is present in shallower water (depths of about 10 to 20 m), most notably in
a small area (approximately 0.09 km2) that extends offshore from Montecito Creek, in the eastern part of the map area. The
presence of coarser grained sediment (coarse sand and possibly gravel) also is inferred in shallower water (depths of 10 to
20 m) offshore from Arroyo Burro, but these deposits are mapped as unit Qmss because they are found within arcuate scour depressions
that have been referred to as "rippled scour depressions" (see, for example, Cacchione and others, 1984; Phillips,
2007) or "sorted bedforms" (see, for example, Murray and Thieler, 2004; Goff and others, 2005; Trembanis and Hume,
2011). Although the general area in which Qmss scour depressions are found is not likely to change substantially, the boundaries
of the unit(s), as well as the locations of individual depressions and their intervening flat sand sheets, likely are ephemeral,
changing during significant storm events. Hydrocarbon-seep-induced topography, which is present most prominently along the
axis of anticlines, includes many features (described by Keller and others, 2007) along the trend of the Mid-Channel Anticline,
about 10 km south of the map area in the Santa Barbara Channel. Geologic map units associated with hydrocarbon emissions in
the map area include grouped to solitary pockmarks (unit Qmp) and asphalt (tar) deposits (unit Qas), as well as areas of undifferentiated
hydrocarbon-related features (unit Qhfu) that probably include a mix of mounds, mud volcanoes, pockmarks, carbonate mats,
and other constructional and erosional "seabed forms" (see Keller and others, 2007), all of which are superimposed
on consolidated, undivided Miocene and Pliocene bedrock (unit Tbu). Offshore bedrock exposures are assigned to the Miocene
Monterey Formation (unit Tm) and to the undivided Miocene and Pliocene bedrock unit (Tbu), primarily on the basis of extrapolation
from the onland geologic mapping of Minor and others (2009), as well as the geologic cross sections of Redin (2005). These
cross sections, which are constrained by industry seismic-reflection data and petroleum well logs, suggest that a considerable
part of the undivided bedrock unit may belong to the Pliocene and Pleistocene Pico Formation. Bedrock is, in some places,
overlain by a thin (less than 1 m?) veneer of sediment, recognized on the basis of high backscatter, flat relief, continuity
with moderate- to high-relief bedrock outcrops, and (in some cases) high-resolution seismic-reflection data; these areas,
which are mapped as composite units Qms/Tbu or Qms/Tm, are interpreted as ephemeral sediment layers that may or may not be
continuously present, depending on storms, seasonal and (or) annual patterns of sediment movement, or longer term climate
cycles. The Santa Barbara Channel region, including the map area, has a long history of petroleum production (Barnum, 1998).
The Monterey Formation is the primary petroleum-source rock in the Santa Barbara Channel, and the Pico Formation is one of
the primary petroleum reservoirs. The bedrock units typically are exposed in structural highs that include uplifts associated
with the partly blind(?), south-dipping Rincon Creek Fault Zone and the outer shelf anticlinal uplift that developed above
the south strand of the Red Mountain Fault in the southwestern part of the map area. The Offshore of Santa Barbara map area
is in the Ventura Basin, in the southern part of the Western Transverse Ranges geologic province, which is north of the California
Continental Borderland (Fisher and others, 2009). This province has undergone significant north-south compression since the
Miocene, and recent GPS data suggest north-south shortening of about 6 mm/yr (Larson and Webb, 1992). The active, east-west-striking
Red Mountain and Rincon Creek Faults and their related folds are some of the structures on which this shortening occurs. This
fault system, in aggregate, extends for about 100 km through the Ventura and Santa Barbara Basins and represents an important
earthquake hazard (see, for example, Fisher and others, 2009). Very high uplift rates of onland marine terraces from More
Mesa (2.2 mm/yr), in the western part of the map area, to Summerland (0.7 mm/yr), a few kilometers east of the map area, are
further indication of rapid shortening in this region (Keller and Gurrola, 2000). References Cited: Barnum, H.P., 1998, Redevelopment
of the western portion of the Rincon offshore oil field, Ventura, California, in Kunitomi, D.S., Hopps, T.E., and Galloway,
J.M., eds., Structure and petroleum geology, Santa Barbara Channel, California: American Association of Petroleum Geologists,
Pacific Section, and Coast Geological Society, Miscellaneous Publication 46, p. 201-215. Cacchione, D.A., Drake, D.E., Grant,
W.D., and Tate, G.B., 1984, Rippled scour depressions of the inner continental shelf off central California: Journal of Sedimentary
Petrology, v. 54, p. 1,280-1,291. Dibblee, T.W., Jr., 1986a, Geologic map of the Carpinteria quadrangle, Santa Barbara County,
California: Santa Barbara, Calif., Dibblee Geological Foundation Map DF-04, scale 1:24,000. Dibblee, T.W., Jr., 1986b, Geologic
map of the Santa Barbara quadrangle, Santa Barbara County, California: Santa Barbara, Calif., Dibblee Geological Foundation
Map DF-06, scale 1:24,000. Fisher, M.A., Sorlien, C.C., and Sliter, R.W., 2009, Potential earthquake faults offshore southern
California from the eastern Santa Barbara channel to Dana Point, in Lee, H.J., and Normark, W.R., eds., Earth science in the
urban ocean--The Southern California Continental Borderland: Geological Society of America Special Paper 454, p. 271-290.
Goff, J.A., Mayer, L.A., Traykovski, P., Buynevich, I., Wilkens, R., Raymond, R., Glang, G., Evans, R.L., Olson, H., and Jenkins,
C., 2005, Detailed investigations of sorted bedforms or "rippled scour depressions," within the Martha's Vineyard
Coastal Observatory, Massachusetts: Continental Shelf Research, v. 25, p. 461-484. Keller, E.A., Duffy, M., Kennett, J.P.,
and Hill, T., 2007, Tectonic geomorphology and hydrocarbon potential of the Mid-Channel anticline, Santa Barbara Basin, California:
Geomorphology, v. 89, p. 274-286. Keller, E.A., and Gurrola, L.D., 2000, Final report, July, 2000--Earthquake hazard of the
Santa Barbara fold belt, California: NEHRP Award #99HQGR0081, SCEC Award #572726, 78 p., available at http://www.scec.org/research/98research/98gurrolakeller.pdf.
Larson, K.M., and Webb, F.H., 1992, Deformation in the Santa Barbara Channel from GPS measurements 1987-1991: Geophysical
News Letters, v. 19, p. 1,491-1,494. Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A., and Brandt, T.R.,
2009, Geologic map of the Santa Barbara coastal plain area, Santa Barbara County, California: U.S. Geological Survey Scientific
Investigations Map 3001, scale 1:25,000, 1 sheet, pamphlet 38 p., available at http://pubs.usgs.gov/sim/3001/. Murray, B.,
and Thieler, E.R., 2004, A new hypothesis and exploratory model for the formation of large-scale inner-shelf sediment sorting
and "rippled scour depressions": Continental Shelf Research, v. 24, no. 3, p. 295-315. Phillips, E., 2007, Exploring
rippled scour depressions offshore Huntington Beach, CA: Santa Cruz, University of California, M.S. thesis, 58 p. Redin, T.,
2005, Santa Barbara Channel structure and correlation sections--Correlation Section no. 34A, Summerland area, Santa Ynez Mountains,
across the east central Santa Barbara Channel to the China Bay area, Santa Cruz Island: American Association of Petroleum
Geologists, Pacific Section, Publication CS 34A, 1 sheet. Reid, J.A., Reid, J.M., Jenkins, C.J., Zimmerman, M., Williams,
S.J., and Field, M.E., 2006, usSEABED--Pacific Coast (California, Oregon, Washington) offshore surficial-sediment data release:
U.S. Geological Survey Data Series 182, available at http://pubs.usgs.gov/ds/2006/182/. Trembanis, A.C., and Hume, T.M., 2011,
Sorted bedforms on the inner shelf off northeastern New Zealand--Spatiotemporal relationships and potential paleo-environmental
implications: Geo-Marine Letters, v. 31, p. 203-214. Weber, K.M., List, J.H., and Morgan, K.L., 2005, An operational Mean
High Water datum for determination of shoreline position from topographic lidar data: U.S. Geological Survey Open-File Report
2005-1027, available at http://pubs.usgs.gov/of/2005/1027/.
Citation
- Title Geology and geomorphology--Offshore of Santa Barbara, California.
-
- creation Date
2018-05-20T03:48:12.234301
Resource language:
Processing environment:
Back to top:
Digital Transfer Options
-
- Linkage for online resource
-
- name Dublin Core references URL
- URL: https://pubs.usgs.gov/ds/781/
- protocol WWW:LINK-1.0-http--link
- link function information
- Description URL provided in Dublin Core references element.
Linkage for online resource
- name Dublin Core references URL
- URL: http://dx.doi.org/10.3133/sim3281
- protocol WWW:LINK-1.0-http--link
- link function information
- Description URL provided in Dublin Core references element.
Linkage for online resource
- name Dublin Core references URL
- URL: http://pubs.usgs.gov/sim/3281/
- protocol WWW:LINK-1.0-http--link
- link function information
- Description URL provided in Dublin Core references element.
Linkage for online resource
- name Dublin Core references URL
- URL: http://pubs.usgs.gov/ds/781/
- protocol WWW:LINK-1.0-http--link
- link function information
- Description URL provided in Dublin Core references element.
Metadata data stamp:
2018-08-06T23:40:12Z
Resource Maintenance Information
- maintenance or update frequency:
- notes: This metadata record was generated by an xslt transformation from a dc metadata record; Transform by Stephen M. Richard, based
on a transform by Damian Ulbricht. Run on 2018-08-06T23:40:12Z
Metadata contact
-
pointOfContact
- organisation Name
CINERGI Metadata catalog
-
- Contact information
-
-
- Address
-
- electronic Mail Address cinergi@sdsc.edu
Metadata language
eng
Metadata character set encoding:
utf8
Metadata standard for this record:
ISO 19139 Geographic Information - Metadata - Implementation Specification
standard version:
2007
Metadata record identifier:
urn:dciso:metadataabout:54d78be9-f488-4325-be80-47d3baa17d37
Metadata record format is ISO19139 XML (MD_Metadata)