Johnny Carson once described the
California seasons – he said they are earthquake, fire, and mudslide. That was
during a particularly rainy winter, after a particularly bad fire season, when
the rain washed away mud from fire-scorched hillsides, then poured it through
houses in Malibu and into the Pacific Ocean.
In Santa Barbara during the last week
of May 2013, we experienced a combination of seasons: fire and earthquake.
·
The
White Fire started Memorial Day in the Santa Ynez Mountains, and burned nearly
2,000 acres – and ruined my summer camping plans!
·
The
following Thursday, a 4.8-magnitude earthquake rocked the coast – epicenter was
offshore, about 3 miles west of Isla Vista, near University of California,
Santa Barbara (UCSB) (2013).
We call this Shake-N-Bake – people
have even been heard, during really hot weather and those famous Santa Barbara
sundowners – saying “Uh Oh – earthquake weather.”
These people are JOKING – or
expressing an oddness in the air.
THERE IS NO CONNECTION BETWEEN WEATHER
AND EARTHQUAKES.
BUT… we at SOS said “Uh Oh!” – for
another reason. Because there IS a connection between earthquakes and seep
flow. And this quake occurred in an area where the seeps are most apparent.
Venoco Inc., received an inquiry
regarding the most recent earthquake off Isla Vista. Their staff geologist
responded by saying that the 4.8 magnitude
event that occurred on May 29 at 07:38 PDT was a normal tectonic event (Venoco
2013).
His comments covered a number of issues
regarding seeps, seismic activity, and oil production that we want to address
in this blog.
1.
California
is located in one of the most active tectonic regions in the world. Earthquakes
are a common occurrence in California, including the Santa Barbara Channel.
There is an established history of significant earthquakes that have occurred
in the Santa Barbara area (e.g. 1812, 1883, 1925, 1941, 1978) (Venoco 2013).
So what is the connection between
seeps and earthquakes?
According to Dr. Ed Keller, professor
in the Departments of Earth Science and Geography, and in the Environmental
Studies Program at UCSB, earthquakes in the seep areas are expected to occur,
and can increase seep flow, as follows:
- Earthquakes in the mid-to high-magnitude 6 range are moderate events, but we can expect larger earthquakes at some time in the future.
- In the earthquake of August 13, 1978, which was a magnitude 5.9 event that occurred offshore off Goleta point…the acceleration, or intensity of shaking, caused the Marine Science Building to shift about one inch on its foundation.
- Santa Barbara and the Channel are part of the so-called ‘earthquake hot zone.’
- Frequent moderate to large earthquakes characterize this zone.
- The most serious seismic hazard is in the Santa Barbara Channel.
- Once an earthquake occurs in the Channel, we would soon know about it (Keller 2008).
And we did!
A 1977 State Lands Commission (SLC)
staff report echoes Dr. Keller’s findings. The report stated that intense seepage
frequently occurs near intersections of faults.
With respect to seismicity and seepage, SLC staff reported that:
- A band of high seismicity coincides with the southern extent of the coastal Santa Barbara oil and tar seep province.
- Active faults occur within several miles of the shoreline along better than 90% of the coast between Point Arguello and San Diego.
- Following the 1925 Santa Barbara earthquake, the Santa Barbara Channel was reportedly covered by thick patches of oil.
- It
is known that a very widespread slick covered a large area of the eastern
Santa Barbara Channel during early October 1974, and fouled the eastern
channel beaches on October 3, 4, and 5.
- There
were also reports of widespread slicks in 1975 and 1976 (SLC 1977).
James M. Galloway, a geologist with
the Pacific Outer Continental Shelf (OCS) Region of the federal agency now
called Bureau of Ocean and Energy Management (BOEM), stated that “Santa Barbara
County is more highly vulnerable to a marine biological mega-catastrophe than
virtually any other location on the planet. No other metropolis sits adjacent
to so many sea floor fractures which overlay such huge subterranean oil
deposits. Local geologists agree Santa Barbara will experience larger seismic
activity. Should a large quake occur offshore, even no stronger than the 1925
quake, history may repeat itself and as reported by early sea-goers, ‘the
entire sea will [again] be black with oil’.”
So we have shown that the Santa Barbara Channel is naturally
a seismically active area and that there is a connection between earthquakes
and increased seepage.
A misconception
still exists - that oil production could cause an earthquake. To understand how unlikely this is, one must
understand the forces and distances involved. Again, from Venoco’s geologist:
2. Oil production at South Ellwood had no
impact or relation to the (May 29, 2013 earthquake) event. The subject
earthquake occurred at a depth of approximately 5 miles (>25,000 feet).
Production at South Ellwood occurs at depths less than 1 mile. The lateral
distance of separation between the platform and the epicenter (surface location)
was approximately 2 miles (Venoco 2013).
Venoco’s geologist
goes on to reference a targeted studied (that he called the most complete and
only study to date) by Plains Exploration & Production Company (PXP) of
their Inglewood Oil Field. Before-during-and-after
measurements of vibration and seismicity, including analysis of data from the
permanently installed California Institute of Technology accelerometer at the
Baldwin Hills, indicated that their activities had no detectable effects on
vibration, and did not induce seismicity (earthquakes). The report stated that any effects of oil
field operations are much shallower than the zones typically associated with
earthquake epicenters along the Newport-Inglewood Fault zone (PXP 2012).
But this
blog entry is called Shake-N-Bake. How do seismicity and seeps relate to our
impending fire season – and seasons to come?
Venoco’s
geologist makes the connection between their Ellwood Field production and
seeps.
3.
One
of the significant impacts from Ellwood production is the reduction of the
natural seeps. A UCSB professor completed a study on that issue several
years ago (Venoco 2013).
We’ve
already shown in previous blog posts that an economic benefit could be realized
by Santa Barbara county services from tax revenue and royalties from that
production. Mark Schniepp, head of the Goleta-based California Economic
Forecast, has stated that “We need a new (job) engine.” Schniepp said if
California used its vast, untapped oil and natural gas deposits during the next
40 years, it would have billions of dollars in revenue and hundreds of
thousands of new jobs (Santa Barbara View 2012).
One of the
services that could be supported is fire protection, and we would ALL benefit.
A March 2012
Santa Barbara Independent article addressed Santa Barbara County funding
struggles with regard to the Fire Department.
It stated that “As Santa Barbara County heads into fire season — with
high winds and hot temps passing through town this week — officials have been
trying to put out their own fire that’s been burning a hole in the
county’s budget.
Capital needs are growing, staffing has been reduced, and
on the heels of a report that says County Fire faces a $1.8-million deficit for
this coming fiscal year to keep services at their current level, a gap that
will grow to almost $15 million four years from now, the Board of Supervisors
decided to shift money around to aid the ailing department in the form of an
increased allocation of property tax revenue. …The problem, of course, is that
when money is given to one agency, it is taken from somewhere else.”
This issue was addressed more recently in a Santa Barbara
News-Press article published on June 13, 2013.
The a article stated that County firefighters could take longer to
respond to emergencies if staff reductions presented to the Santa Barbara
County Board of Supervisors are approved. The article quoted Michael Dyer,
County Fire Chief, whose opinion is that budget cuts would reduce the
department’s response and ability to address critical situations.
We all know
what this fire season has brought thus far.
Why should any of our county
departments be limited...as we continue to Shake-N-Bake … and seep?
REFERENCES
Galloway,
J.M. Geologist, Pacific OCS Region,
Bureau of Ocean Energy Management.
Independent
2012. Fighting Fire with Cash.
County Reworks Money Streams to Help Underfunded Department.
Thursday, May 24, 2012. By Chris Meagher.
Keller 2008. History of Santa Barbara
Earthquakes. Dr. Ed Keller, UCSB Dr. Ed Keller Department of Earth
Science, UCSB. Santa Barbara News-Press, August 18, 2008.
PXP 2012.
Hydraulic Fracturing Study PXP Inglewood Oil Field. Prepared
for Plains Exploration & Production Company Los Angeles County,
Department of Regional Planning. Prepared by Cardno ENTRIX (www.cardnoentrix.com)
State Lands Commission. (SLC) 1977.
California Offshore Gas, Oil and Tar Seeps.
Santa Barbara News Press 2013. County
Fire Could See Cuts. Thursday June 13, 2013. By Emily Parker. http://www.newspress.com/Top/Article/article.jsp?Section=LOCAL&ID=566722047909167136&Archive=true
Santa Barbara View 2012. Santa Barbara
Business Beat, Ray Estrada. November 9, 2012.
Venoco 2013. Personal communication
with Lisa Rivas., Government Relations Manager.
