Onshore and Offshore Geologic Map of the Coal Oil Point

Area, Southern California

By Pete Dartnell, James E. Conrad, Richard G. Stanley, and Guy R. Cochrane

Pamphlet to accompany

Scientific Investigations Map 3124

U.S. Department of the Interior 

U.S. Geological Survey 
U.S. Department of the Interior

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia 2010 

This report and any 

updates to it are available

online at: http://pubs.usgs.gov/sim/3124/ 

For more information on the USGS—the Federal source for science about the Earth,

its natural and living resources, natural hazards, and the environment:

World Wide Web: http://www.usgs.gov

Telephone: 1-888-ASK-USGS

Suggested citation:

Dartnell, P., Conrad, J.E., Stanley, R.G., and Cochrane, G.R., 2010, Onshore and offshore geologic map of the Coal 

Oil Point area, southern California, U.S. Geological Survey Scientific Investigations Map 3124. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report.

2
Contents

Introduction......................................................................................................................................................................1

Geologic Maps ................................................................................................................................................................2

 General Features of Geologic Maps...........................................................................................................................2

 Onshore Geologic Maps.............................................................................................................................................2 

 Offshore Geologic Maps.............................................................................................................................................4 

 Combined Onshore and Offshore Geologic Maps......................................................................................................4 

Coal Oil Point Geologic Mapping.....................................................................................................................................5 

 Offshore Mapping.......................................................................................................................................................5 

 Offshore Seismic Profiling ..........................................................................................................................................9 

 Offshore Ground-truthing..........................................................................................................................................10

 Offshore Sediment Samples.....................................................................................................................................11

 Onshore-Offshore Geologic Map..............................................................................................................................11

Conclusion.....................................................................................................................................................................12

References Cited...........................................................................................................................................................14

Disclaimer......................................................................................................................................................................15

Figures

1. Location of Coal Oil Point onshore and offshore geologic map. .................................................................................1

2. Example of a geologic map with different colored polygons representing different bedrock or surficial deposits.......3 

3. Areas surveyed offshore the Coal Oil Point region by institution.................................................................................6 

4. Close-up map view of the onshore-offshore DTM.......................................................................................................9 

5. Bathymetric-Topographic Profile across the land - seafloor interface near Isla Vista.................................................9 

6. Seismic profile collected just east of Coal Oil Point...................................................................................................10

7. USGS towed camera sled.........................................................................................................................................10

8. Video screens and programmable keypad................................................................................................................11

Tables

1. Original Bathymetric and Topographic Datasets used to create the bathy-topo digital terrain 

model............................................................................................................................................7 

2. Measured statistics of overlapping bathymetric datasets.........................................................................8 

3
Introduction

Geologic maps that span the shoreline and include both onshore and offshore areas are 

potentially valuable tools that can lead to a more in depth understanding of coastal environments. Such 

maps can contribute to the understanding of shoreline change, geologic hazards, both offshore and 

along-shore sediment and pollutant transport. They are also useful in assessing geologic and biologic 

resources. Several intermediate-scale (1:100,000) geologic maps that include both onshore and offshore 

areas (herein called onshore-offshore geologic maps) have been produced of areas along the California 

coast (see Saucedo and others, 2003; Kennedy and others, 2007; Kennedy and Tan, 2008), but few 

large-scale (1:24,000) maps have been produced that can address local coastal issues. 

A cooperative project between Federal and State agencies and universities has produced an 

onshore-offshore geologic map at 1:24,000 scale of the Coal Oil Point area and part of the Santa 

Barbara Channel, southern California (fig. 1). As part of the project, the U.S. Geological Survey 

(USGS) and the California Geological Survey (CGS) hosted a workshop (May 2nd and 3rd, 2007) for 

producers and users of coastal map products (see list of participants) to develop a consensus on the 

content and format of onshore-offshore geologic maps (and accompanying GIS files) so that they have 

relevance for coastal-zone management. The USGS and CGS are working to develop coastal maps that 

combine geospatial information from offshore and onshore and serve as an important tool for addressing 

a broad range of coastal-zone management issues. The workshop was divided into sessions for 

presentations and discussion of bathymetry and topography, geology, and habitat products and needs of 

end users. During the workshop, participants reviewed existing maps and discussed their merits and 

shortcomings. 

Figure 1. Location of Coal Oil Point onshore-offshore geologic mapping. 

4
This report addresses a number of items discussed in the workshop and details the onshore and 

offshore geologic map of the Coal Oil Point area. Results from this report directly address issues raised 

in the California Ocean Protection Act (COPA) Five Year Strategic Plan. For example, one of the 

guiding principles of the COPA five-year strategic plan is to “Recognize the interconnectedness of the 

land and the sea, supporting sustainable uses of the coast and ensuring the health of ecosystems”. 

Results from this USGS report directly connect the land and sea with the creation of both a seamless 

onshore and offshore digital terrain model (DTM) and geologic map. One of the priority goals (and 

objectives) of the COPA plan is to “monitor and map the ocean environment to provide data about 

conditions and trends.” Maps within this report provide land and sea geologic information for mapping 

and monitoring nearshore sediment processes, pollution transport, and sea-level rise and fall. 

Geologic Maps

General Features of Geologic Maps

Geologic maps show the distribution, nature, and age relations of bedrock units; surficial 

deposits (for example, sand along beaches and rivers), geologic structures such as faults and folds; and, 

in some cases, mineral deposits. Geologic maps are commonly used by scientists, planners, and 

decisionmakers in both government and industry to evaluate geologic hazards; to assess known and 

potential energy, mineral, and water resources; and to guide land-use policies. 

Geologic maps are often shown overprinted on topographic maps, which include contour lines 

(lines that link points of equal elevation) to show the shape of any part of the Earth's surface. Geologic 

maps are not the same as substrate maps, which may superficially resemble geologic maps because they 

show the surface distribution of bedrock and surficial deposits (for example, gravel, sand, and mud). 

However, unlike geologic maps, substrate maps do not distinguish different bedrock units from each 

other, do not show the geologic ages of the bedrock units, and do not depict geologic structures. 

Onshore Geologic Maps

Onshore geologic maps are prepared using detailed observations of rocks at many outcrops, 

usually by one or several geologists traveling on foot and assisted by motor vehicles, boats, or aircraft. 

At each outcrop, many different kinds of information are gathered and recorded, including (1) color, 

composition, texture, and structure of the rock or surficial deposit; (2) detailed measurements of the 

orientations of features such as sedimentary layering, fractures, faults, and folds; and (3) details that 

might reveal the age of the rock, such as fossils from sedimentary rocks or samples of igneous rocks that 

can be isotopically dated in the laboratory. These outcrop observations are often supplemented by 

examination and interpretation of vertical aerial photographs. 

Most geologic maps use colored polygons to show the distribution of different kinds of bedrock 

and surficial deposits (fig. 2). Each color represents a different geologic unit, and each unit is also 

labeled with letter symbols that contain information about the age of the unit and its lithology; for 

example, the symbol “Qls” might be used for landslide deposits of Quaternary age, whereas the symbol 

"Tms" might be used for a sandstone unit that was deposited during the Miocene Epoch of the Tertiary 

Period. 

5
Figure 2. Example of a geologic map with different colored polygons representing different bedrock or 

suficial deposits (from Minor and others, 2009).

The boundary between two different rock units is called a contact and is shown on the geologic 

map as a line. On most geologic maps, thick lines are used to show faults, whereas thin lines are used to 

show both depositional and intrusive contacts. A contact that is located accurately is shown on the map 

as a solid line, but a contact that is located only approximately (perhaps because it is partly hidden by 

soil or vegetation) is shown as a dashed line. A contact between two bedrock units that is completely 

covered by surficial deposits is shown as a dotted line. Other lines that appear on geologic maps show 

the crests of folds and the locations of cross sections and these are usually labeled with symbols to 

distinguish them from contact lines. A wide variety of other kinds of symbols are used to show 

additional geologic features such as oil and gas seeps, occurrences of fossils, and places where a 

geologist has measured the orientation of layering in sedimentary rocks, or the orientation of structural 

features such as faults and joints. 

Geologic maps are available for much of the onshore western United States at a variety of scales. 

In coastal central and southern California, for example, published geologic maps are available for most 

areas at a scale of 1:24,000, which is suitable for most scientific, industrial, and government purposes. 

These maps, however, vary considerably in the degree to which they show geologic details as well as 

the accuracy of locations; many published onshore geologic maps are generalized and, therefore, of 

6
reconnaissance quality only. In much of coastal California, new and detailed mapping of both bedrock 

and Quaternary units is still needed to (1) adequately identify and evaluate geologic hazards such as 

landslides, liquefaction, seismic shaking, and surface-fault rupture; (2) assess known and potential 

energy, mineral, and water resources; and (3) provide detailed and reliable information for use in 

preparing and implementing land-use policies.

Offshore Geologic Maps

Few geologic maps at a scale of 1:24,000 are available for offshore areas, largely because direct 

observation of geologic materials on the seafloor is difficult and costly. However, along some parts of 

the coast, modern marine geophysical techniques such as multibeam sonar and bathymetric lidar have 

been used to collect remarkably detailed bathymetric data. Also, many multibeam and bathymetric sidescan systems collect co-registered acoustic backscatter that can be used in conjunction with the 

bathymetry data and seafloor video or sediment samples to create substrate maps that show the 

distribution of bedrock, sand, and mud. Some seafloor video shows physical characteristics that allow 

preliminary interpretations of rock type, such as conglomerate, sandstone, or volcanic rock. These 

images however, provide no information on the ages of the rocks. 

Information on the lithologies and ages of rocks on the seafloor can only be obtained by direct 

observation, sampling, and analysis of rocks from outcrops that occur on and beneath the seafloor. 

Samples from the bottom of the sea are usually obtained from dredge hauls and shallow cores, and less 

often from boreholes and by direct acquisition by human divers or remotely controlled vehicles. 

Photographs and videos of the seafloor can provide information on the nature, thickness, and 

distribution of surficial sediments and, in areas of bedrock outcrop, the character and general orientation 

of layering, faults, and fractures. Seismic-reflection profiling is generally easier to obtain offshore than 

onshore and can reveal sediment thickness as well as the locations, geometries, and relative ages of 

unconformities, faults, and folds. Acquisition and modeling of gravity and magnetic data can provide 

important insights into geologic structure in areas where geologic units differ from each other in density 

and magnetic properties.

Combined Onshore and Offshore Geologic Maps

The preparation of truly seamless onshore-offshore geologic maps presents several challenges. 

The shoreline is nearly always an abrupt seam because, as a fundamental boundary between the 

terrestrial and marine realms, the shoreline marks an abrupt and dramatic change in depositional 

processes and surficial deposits. In coastal California, for example, Quaternary surficial deposits in 

onshore areas are created and modified by terrestrial processes such as rivers and blowing wind, 

whereas Quaternary surficial deposits in nearby offshore areas are created and modified by marine 

processes such as waves, tidal currents, and longshore drift. 

In some coastal areas, the same bedrock geologic units and structures that have been identified 

and mapped onshore may continue into the offshore. Nevertheless, detailed geologic observations are 

usually easier to make on land than on the seafloor, and most onshore-offshore geologic maps will show 

more geologic detail (for example, more measurements on the orientation of sedimentary layering, as 

well as more faults and folds) onshore than offshore. An additional challenge is posed by the way that 

certain rock units are distinguished from each other. For example, the Monterey and Sisquoc Formations 

near Santa Barbara, California, are mudstone units that are distinguished from each other on the basis of 

7
subtle changes in texture, mineralogy, and fossil content; such features are easily observed in onshore 

outcrops but are much more difficult to observe in offshore outcrops. Therefore, on combined onshore 

and offshore geologic maps, it may be necessary to depict fewer, more generalized bedrock units in the 

offshore. 

In many places along the California, Oregon, and Washington coasts - for example, in parts of 

Sonoma, San Mateo, and Santa Barbara Counties, California - the location of the shoreline is coincident 

with, or in close proximity to, faults that are poorly understood because their position in the surf zone 

makes them difficult to study. Closely coordinated mapping efforts by teams of geologists and 

geophysicists working both onshore and offshore could provide a better understanding of the structural 

and tectonic significance of these faults and their seismic-hazard potential. 

Coal Oil Point Geologic Mapping

In an effort to resolve the challenges of producing an onshore-offshore geologic map, a 1:24,000 

scale geologic map was created for the Coal Oil Point area and part of the Santa Barbara Channel. This 

area was chosen due to its unique setting and the existence of many of the data sets needed to produce 

this map. The Coal Oil Point area includes coastal cliff erosion near Isla Vista between Coal Oil and 

Goleta Points, a number of faults that trend across the land-sea boundary, an offshore region with some 

of the highest hydrocarbon seepage rates along the West Coast, and a large active submarine landslide 

located about three nautical miles offshore that has the potential to generate tsunamis. This area was 

also chosen because detailed, onshore 1:24,000-scale geologic mapping was recently completed along 

the Santa Barbara coastal plain and mountains (Minor and others, 2009). 

Offshore Mapping

The offshore geologic interpretations are based on several data sets including, bathymetry, 

acoustic backscatter, seismic profiles, seafloor video, photographs, and sediment samples. A seamless 

topographic-bathymetric digital terrain model (DTM) at 10-m resolution was used as a base map for the 

interpretations. The bathymetry was compiled from a number of surveys that were collected over a 

period of 25 years by various institutions (fig. 3). 

8
Figure 3. Areas surveyed offshore the Coal Oil Point region by institution. USGS-U.S. Geological 

Survey; CSUMB-California State University, Monterey Bay; NOAA-National Oceanographic and 

Atmospheric Administration; MBARI-Monterey Bay Aquarium Research Institute. 

Different mapping systems were used including pole-mounted bathymetric side scan systems, 

pole-mounted multibeam echosounders, hull-mounted multibeam echosounders, and single-beam 

echosounders. The surveys (table 1) mapped at various resolutions (2 m to over 10 m) and the 

soundings were referenced to different vertical datums (for example, MLLW and NAVD88). As part of 

this project, all of the surveys were projected to a common horizontal datum (NAD83) using standard 

GIS transformations and a common vertical datum (NAVD88) using NOAA’s VDatum tool. The 

topography was compiled from publicly available ifSAR data (table 1). 

9
Table 1. Original Bathymetric and Topographic Datasets used to create the bathy-topo digital terrain 

model. 

 

Institution Year Original Horizontal / 

Vertical Datum

Original

Resolution Source

U.S. Geological 

Survey 2007 WGS84 / NAVD88 2-m This report (partial, 10-m data)

U.S. Geological 

Survey 2006 WGS84 / MLLW 2-m This report (10-m data)

California State 

Univ. - Monterey 

Bay

2007 WGS84 / NAVD88 2-m http://seafloor.csumb.edu/

Monterey Bay 

Aquarium Research 

Institute

1998 WGS84 / NAVD88 10-m http://www.ngdc.noaa.gov/mgg/

bathymetry/multibeam.html

Fugro Pelagos Inc. 2008 NAD83 / NAVD88 5-m http://seafloor.csumb.edu/

National 

Oceanographic and 

Atmospheric 

Admin. (NOAA) -

Survey H10165

1985 NAD83 / MLLW varies http://www.ngdc.noaa.gov/mgg/

bathymetry/hydro.html

National 

Oceanographic and 

Atmospheric 

Admin. (NOAA)

2002/2003 WGS84 / NAVD88 3-m http://www.csc.noaa.gov/digitalcoast/

Depth offsets did occur between overlapping bathymetric data sets (table 2) even though they 

were projected to common horizontal and vertical datums. There may be a number of reasons for these 

depth offsets that include different sonar systems mapping at different frequencies and resolutions; 

errors in horizontal and vertical datum transformations; and errors measuring vertical and horizontal 

offsets between the sonar head, GPS, and vehicle-motion unit aboard the survey vessels.

10
Table 2. Measured statistics of overlapping bathymetric datasets. USGS, U.S. Geological Survey; 

CSUMB, California State University, Monterey Bay; MBARI, Monterey Bay Aquarium Research 

Institute; NOAA, National Oceanic and Atmospheric Administration; Fugro, Fugro Pelagos Inc. 

Surveys Mean Difference 

(meters)

Standard Deviation 

(meters)

USGS2006 –

USGS2007 0.13 0.55

USGS2006 -

CSUMB 0.48 0.28

USGS - MBARI 0.35 0.51

USGS – NOAA 

(H10165) 0.46 1.2

Fugro - MBARI 0.4 0.8

Once all of the data sets were transformed to a common datum, the higher resolution multibeam 

and bathymetric side-scan surveys as well as the ifSAR DEM were de-sampled to 10-m resolution grids. 

Initially, in the nearshore area (surf zone), there was a 50 m to more than 200 m gap between the 

shallowest soundings of the NOAA single-beam survey and the ifSAR DEM. To fill this gap, the 

nearshore portion of the DEM was converted to a point coverage and exported as an XYZ file. This 

XYZ data was merged with the NOAA single-beam soundings (XYZ), as well as a digital coastline (0-

m depth). A 10-m surface was created from the new merged XYZ file using a GIS spline procedure. 

This procedure creates a surface that closely passes through each XYZ point (depth, coastline, and 

elevation). 

All of the 10-m grids including the bathymetric surveys, nearshore spline surface, and DEM 

were merged into one nearly seamless 10-m onshore-offshore DTM using a GIS “merge” function (fig. 

4). Bathy-topo profiles (fig. 5) show a relatively smooth transition between the land-seafloor interface as 

well as between the different bathymetric data sets. 

Since this seamless bathymetric-topographic DTM was created for this project, other similar 

DTMs have been made public in and around this region including NOAA’s 10-m Inundation Model

(Carignan and others, 2009), as well as Barnard and Hoover (2010). 

11
Figure 4. Close-up map view of the onshore-offshore DTM near the Isla Vista area. 

The green area shows land, while the blue area shows the seafloor. Line A-A’ shows the 

location of the bathy-topo profile in fig 5 while “X” shows the transition between two 

bathymetric datasets. 

Figure 5. Profile A-A’ across the land - seafloor interface near Isla Vista. The profile crosses onshore 

10-m ifSAR DEM, nearshore gridded NOAA single-beam bathymetry, and offshore USGS bathymetric 

sidescan bathymetry. The black vertical line (X) in the profile shows the location of the transition 

between bathymetric datasets. See Figure 4 for the profile location. 

Offshore Seismic Profiling

In July of 2007 seismic sub-bottom profiles using Huntec and Chirp systems were collected 

within the Santa Barbara Channel (Sliter and others, 2008). Four profiles were collected within this 

study area orientated perpendicular to shore and show folded bedrock exposed at the seafloor (location 

A, fig. 6), as well as sediment covering folded bedrock (location B, fig. 6). Gas bubbles are also seen in 

the water column above active hydrocarbon seeps. These profiles along with the high-resolution 

12
bathymetry and backscatter data help define the distribution and characteristics of bedrock units 

exposed on the seafloor as well as the distribution and thickness of unconsolidated marine sediments. 

Figure 6. Seismic profile collected just east of Coal Oil Point, California showing folded bedrock, 

sediment, and gas seeps. 

Offshore Ground-Truthing

To obtain visual geologic observations of the seafloor (such as rock or sediment) to relate to the 

remotely collected multibeam and bathymetric side-scan data, the USGS collected seafloor video from a 

towed camera sled. The sled is approximately 2 m by 0.5 m and houses a downward-looking video 

camera, a forward-looking video camera, and a downward-looking high-definition video camera (fig. 7). 

Paired lasers associated with each video camera are spaced 16 cm apart and provide scale. 

Figure 7. USGS towed camera sled. 

13
Both the downward- and forward-looking regular video cameras had a real-time feed up to the 

ship where the video could be observed as well as recorded onto miniDV tapes (fig. 8). From the 

streaming video, observations, such as geologic composition and biologic cover were recorded over a 

10-second period, every minute using programmable keypads (fig. 8). Each observation was stamped 

with a time and geographic coordinates both at the beginning and end of the observation. The output 

from the keypads is a comma delimited text file that can be quickly converted to a GIS shapefile and 

overlayed on the sonar data to help with interpretations. 

Figure 8. Video screens aboard the ship showing real-time seafloor video. Insert figure shows one of 

the programmable keypads. 

Offshore Sediment Samples

While no sediment samples were collected in the study area for this project, existing sample 

information (texture) was obtained from the usSEABED database (Reid and others, 2006). 

Onshore and Offshore Geologic Map

The extent of the onshore-offshore geologic map of this report is the same size and shape as a 

typical USGS 7.5 minute quadrangle. However, an existing quadrangle (Dos Pueblos Canyon or Goleta) 

was not used because they mainly include the land areas with very little offshore region. Therefore, a 

base for the map area was generated centered on Isla Vista with approximately equal land and offshore 

coverage. 

14
The offshore geologic interpretations were based on the swath bathymetry, acoustic backscatter, 

seismic profiles, sediment samples, and seafloor video and photography. In GIS software ArcMap, 

bathymetric and acoustic backscatter maps were created at 1:24,000 scale and exported as Adobe 

Illustrator files. Geologic interpretations including geologic unit polygons, contacts, and folds were 

digitized using Adobe Illustrator and then imported back into the GIS software. The polygons, contacts, 

and folds were converted to shapefiles to merge with the onshore geology of Minor and others, 2009. 

All files, both onshore and offshore, were projected to UTM zone 11 WGS84 coordinates. 

The onshore geology is described in detail in Minor and others (2009), and includes sedimentary 

rocks of Oligocene to Holocene age. The offshore geologic units are of Miocene age and younger, and 

include the Miocene Monterey Formation (Tm), upper Miocene and lower Pliocene Sisquoc Formation 

(Tsq), and younger Pliocene marine sediments. In the nearshore, these units can be recognized when 

contiguous with units identified onshore and in some cases confirmed with paleontological ages from 

dartcore samples. Onshore, the Monterey Formation is divided into lower, middle and upper units (Tml, 

Tmm, and Tmu), but these are not easily recognizable in the offshore so there the Monterey Formation 

(Tm) is not subdivided. Further offshore, a large bedrock outcrop on the mid to outer shelf is known 

from dartcore sampling to include the Monterey and Sisquoc Formations as well as younger marine 

sediments that contain microfossils of Repettian age, but these data are not detailed enough to permit 

subdivision of these units so they are mapped as undivided Miocene and Pliocene rocks (Tmp). 

These Miocene and Pliocene rocks are warped into asymmetric folds that trend generally eastwest, roughly parallel to the coastline. At least some of these folds probably root into blind faults at 

depth. Presumably, these rocks underlie the entire offshore shelf and slope region, but they are in most 

places covered by unconsolidated marine sediments consisting of sand, silt, and mud of Holocene (and 

possibly older) age (Qms), which is as much as 10 m thick in places. In addition, small deposits of 

unconsolidated marine gravel (Qmg), and a 1- to 2-m-thick unit of sedimentary rocks, at least in part 

consisting of cobble conglomerate (Qys) occur on the shelf. 

Numerous asphalt deposits (Qas) associated with hydrocarbon seeps and gas vents occur 

onshore and were confirmed in the offshore with seafloor video. Many are too small to be shown on the 

map but the larger deposits cover as much as several hundred square meters. Asphalt occurrences are 

often localized along bedrock structures such as faults or the crests of antiforms. These deposits appear 

as bathymetric features that appear similar to bedrock outcrops but are distinguished from them by 

having low acoustic backscatter. 

The head of the Goleta slide complex is located along the shelf edge in the southwest quadrant 

of the study area and is divided into five sub-units using the classification of Greene and others (2006). 

Conclusion

Onshore geologic maps are used by scientists and planners to evaluate geologic hazards; to 

assess known and potential energy, mineral, and water resources; and to guide land-use policy. 

Combined onshore-offshore geologic maps have the added benefit of addressing local coastal issues 

15
including shoreline changes, coastal geologic hazards such as submarine landslides, both offshore and 

along-shore sediment and pollutant transport, and to assess nearshore geologic and biologic resources. 

Offshore geologic mapping is complicated by the fact that geologists can rarely view in situ

geologic units. Most offshore mapping is completed using remotely sensed information. The Coal Oil 

Point offshore geologic interpretations were based on swath bathymetry data, acoustic backscatter data, 

seismic profiles, sediment samples, as well as seafloor video and photography. The offshore region is 

composed of Holocene aged marine sediment and Pliocene and Miocene bedrock outcrops of the 

Monterey Formation, Sisquoc Formation, and marine sedimentary rocks containing Repettian-age 

fossils. The offshore area also includes faults and folds that trend mainly east-west and a few of these 

extend onshore. 

The Coal Oil Point onshore-offshore geologic map and DTM will help local coastal managers 

and researchers better understand coastal issues including shoreline erosion near Isla Vista, nearshore 

hydrocarbon seeps, tsunami potential from the nearby Goleta slide complex, and alongshore sediment 

and pollutant transport along the northern Santa Barbara Channel. 

 

16
References Cited

Barnard, P.L., and Hoover, D., 2010, A seamless, high-resolution coastal digital elevation model (DEM) 

for southern California: U.S. Geological Survey Data Series 487, 8 p. and database. Available at 

http://pubs.usgs.gov/ds/487/. 

Carignan, K.S., Taylor, L.A., Eakins, B.W., Warnken, R.R., Lim, E.D., and Medley, P.R., 2009, Digital 

elevation model of Santa Barbara, California; procedures, data sources and analysis: NOAA 

Technical Memorandum NESDIS NGDC-29. Available at 

http://www.ngdc.noaa.gov/mgg/inundation/tigp/ngdc/data/santa_barbara_ca/santa_barbara_ca.pdf

Fisher, M.A., Normark, W.R., Greene, H.G., Lee, H.J., and Sliter, R.W., 2005, Geology and 

tsunamigenic potential of submarine landslides in Santa Barbara Channel, southern California: Marine 

Geology, v. 224, p. 1-22. 

Greene, H.G., Mural, L.Y., Watts, P., Maher, N.A., Fisher, M.A., Paull, C.E., and Eichhubl, P., 2006, 

Submarine landslides in the Santa Barbara Channel as potential tsunami sources: Natural Hazards and 

Earth System Sciences, v. 6, p. 63-88. 

Kennedy, M.P.,Tan, S.S.,Bovard, K.R.,Alvarez, R.M.,Watson, M.J. and Gutierrez, C.I., 2007, Geologic 

map of the Oceanside 30x60-minute quadrangle, California: California Geological Survey, Regional 

Geologic Map No. 2, scale 1:100000. 

Kennedy, M.P. and Tan, S.S., 2008, Geologic map of the San Diego 30' x 60' quadrangle, California: 

California Geological Survey, Regional Geologic Map No. 3, scale 1:100000. 

Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A., 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. Available at http://pubs.usgs.gov/sim/3001/

Reid, J., Zimmermann, J.C., Williams, M.S., and Field, M., 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/. 

Saucedo, G.J., Greene, H.G., Kennedy, M.P., Bezore, S.P., Tilden, J., Little, J.D., Mascorro, M.T., and 

Ford, E.W., 2003, Geologic map of the Long Beach 30' x 60' quadrangle, California (preliminary): 

California Geological Survey, Regional Geologic Map Series, 1:100,000 scale. 

Sliter, R.W., Triezenberg, P.J., Hart, P.E., Draut, A.E., Normark, W.R., and Conrad, J.E., 2008, Highresolution chirp and mini-sparker seismic-reflection data from the southern California continental 

shelf; Gaviota to Mugu Canyon: U.S. Geological Survey Open-File Report 2008-1246. Available a 

http://pubs.usgs.gov/of/2008/1246/. 

17
Disclaimer

The data and maps provided in this report are not intended for navigational purposes. 

Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, 

these data and information are provided with the understanding that they are not guaranteed to be 

usable, timely, accurate, or complete. Users are cautioned to consider carefully the provisional nature of 

these data and information before using them for decisions that concern personal or public safety or the 

conduct of business that involves substantial monetary or operational consequences. Conclusions drawn 

from, or actions undertaken on the basis of, such data and information are the sole responsibility of the 

user. 

Neither the U.S. Government nor any agency thereof, nor any of their employees, contractors, or 

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Trade, firm, or product names and other references to non-USGS products and services are provided for 

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accuracy. 

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