Ventura-Santa Barbara Earthquake Faults Map

Fault Activity in Ventura and Santa Barbara

Active Faults:

San Andreas Fault: Though not directly within Ventura or Santa Barbara, its proximity poses a significant seismic hazard.
Southern San Andreas Fault System: Includes the nearby faults like the San Jacinto Fault Zone and the Elsinore Fault Zone.
Santa Ynez Fault: Runs through Santa Barbara County and is capable of producing moderate to large earthquakes.

Earthquake Hazards

Hazards Faced:

Liquefaction: Particularly in areas with loose, water-saturated soils, causing ground instability.
Tsunamis: The shoreline near Channel Islands could potentially experience tsunamis triggered by undersea earthquakes.
Landslides: Especially in hilly and mountainous areas prone to slope instability.
Building and Structure Collapse: Depending on construction standards and seismic retrofitting.
Fires: Due to ruptured gas lines and electrical infrastructure.

Areas Prone to Worst Shaking:

Areas near active faults like the Santa Ynez Fault and those with loose, water-saturated soils are particularly vulnerable to intense shaking.

Major Earthquakes in the Last 100 Years

Notable Quakes:

Some major earthquakes that have affected Ventura and Santa Barbara in the last century include:

1925 Santa Barbara Earthquake: Magnitude 6.8, caused significant damage in Santa Barbara.
1971 San Fernando Earthquake: Magnitude 6.6, though more impactful in Los Angeles, had effects felt in Ventura and Santa Barbara counties.

Tsunami Risk from Channel Islands

Tsunami Potential:

A major quake near the Channel Islands could potentially generate a tsunami affecting the Ventura and Santa Barbara shoreline, though the risk depends on the specific characteristics of the earthquake.

Indigenous Perspectives on Earthquakes

Native American Responses:

Historically, local indigenous tribes in Ventura and Santa Barbara, such as the Chumash people, had cultural and practical responses to earthquakes. They often saw earthquakes as powerful and significant events, sometimes referred to as "momoy," meaning shaking or trembling in Chumash language.

Santa Barbara Fault Map

Carpinteria Fault Map

Ventura Fault Map

Channel Islands Fault Map

Point Conception Fault Map

Solvang Fault Map

Fault Attributes Key

NAME is an 80-character field for the name of the fault (including section name,
i.e., Denali fault, Holitna section). Fault and section are lower case.

CODE is a three-integer field.that defines certainty or reliability of field mapping
(integer one), time of most recent movement (integer two), and amount or rate of slip (integer three).
CODE is composite of the single integer fields ACODE, SLIPCODE, and FCODE
and determines the line type (fault trace) to be plotted.

NUM is a six-character unique USGS identifier that defines a fault or section id. Simple fault
ids are only numeric; section ids are alpha numeric.

AGE is the upper bounding time of the most recent surface-deforming earthquake. The allowable
choices are provided in a pull-down menu.

ACODE is the second integer in CODE and defines the upper bounding time of the most recent
surface-deforming earthquake.
Permissible values are between 1 and 6: 1=historic «150 years; red =cmyk 1096680);
2= post glacial (15,000 years; orange = cmyk 1 38 1000);
3 = late Quaternary «130,000 years; green> cmyk 1002500);
4 =middle and late Quaternary «750,000 years: blue > cmyk 1004440);
5 =Quaternary «1,600,000 years; black 5);
6 = Class B (black halftone)
In the text documentation, Quaternary faults (integer two, 1-5) are Class A structures. Questionable or
suspected structures are Class B (integer two, 6).

SLIPRATE is the assigned slip rate category.

SLIPCODE is the third integer in CODE and defines the assigned slip rate category. Permissible
values are between 1 and 4 and determines line width:
1=>5 mm/year (extra wide; .048):
2 =1-5 mm/year (wide; .0325):
3 =0.2-1 mm/year (medium; .025);
4 =<.2 mm/year (thin; .015)

SLIPSENSE is normal, reverse, strike slip, thrust

DIPDIRECTION is one of the eight quadrant dip directions for the entire fault or section, not the
individual arc. C = center E =east N_ =north NE =northeast NW =northwest S =south SE =southeast SW =
southwest W_ =west
SLIPDIRECT (we are not using that field anymore and can be left empty) FCODE is the first integer
in CODE and defines how well the fault is located and expressed in the landscape. Permissible values are

between 1 and 3:
1 = fault landforms are more continuous than discontinuous and mapping is accurate at
given MAPPEDSCALE (solid);
2 = fault landforms are more discontinuous than continuous and mapping is accurate at
given MAPPEDSCALE (dashed);
3 = location of fault is inferred (dotted)
FTYPE is one of three allowable choices provided in a pull-down menu: Well constrained (FCODE 1),
Moderately constrained (FCODE 2), and Inferred (FCODE 3)

MAPPEDSCALE is one of four allowable choices provided in a pull-down menu.
Mapped scale will control visualization of the fault at various scales.
1:24,000, fault should be more continuous than discontinuous and mapping is accurate at <10,000 scale.
1:50,000, fault should be more continuous than discontinuous and mapping is accurate at <25,000 scale.
1:100,000, fault could be more discontinuous than continuous and mapping is accurate at <50,000 scale.
1:250,000, fault location may be inferred or is poorly constrained.

Data source: USGS
CCCarto is not responsible for data errors or omissions, use as reference only.
copyright cccarto.com 2024