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The
Santa Barbara, California, Earthquakes and Tsunami(s) of December
1812
George
Pararas-Carayannis
(Excerpts
from a study of historical tsunamis in California undertaken
under contract with Marine Advisors, the U.S. Nuclear Regulatory
Agency and the U. S. Army Coastal Engineering Research Center
in connection with the licencing of the San Onofre Nuclear Power
Plant and subsequent licencing of Units 2 and 3)
©) Copyright
1967 George Pararas-Carayannis
Introduction
 As mentioned elsewhere in these
pages, the relative tsunami threat for local tsunamis in California
can be considered as being relatively low because of the low
recurrence frequencies. Large, locally-generated tsunamis in
California are estimated to occur once every 100 years. Thirteen
possible tsunamis have been observed or recorded from local earthquakes
between 1812 and 1988. These tsunami events were poorly documented
and some are very questionable. There is no doubt that earthquakes
occurring along submarine faults off Santa Barbara, could generate
large destructive local tsunamis. In fact in December of 1812,
local earthquakes occured, each capable of tsunami generation.
Perhaps the size of the 1812 tsunami was exaggerated in the historical
records, but one and possibly two large tsunami events did occur
in the area.
Santa Barbara
Tsunami(s) of 1812 - A Source of Controversy
There greatest controversy regarding
the generation of tsunamis from local earthquakes in California
has been about events which occurred along the Santa Barbara
coast region in December of 1812. The December 1812 earthquakes
and resulting tsunami waves have been the subject of research
by many scientists. Historical accounts reported large tsunami
waves with no clear documentation on the chronology of events.
There is no doubt that one and possibly two large tsunami events
were generated by the December 1812 earthquakes in the Santa
Barbara region. However, the tsunamis could not have been as
large as they have been described in the historical accounts.
Furthermore, tsunami events of such magnitude would place in
different perspective the suseptibility of Southern California
to the tsunami hazard (from local earthquakes)
Because of the importance
of these events, a thorough investigation of the literature was
undertaken, initially in the early 1960's under contract with
Marine Advisers in connection with the design and licensing of
the San Onofre Nuclear Power Plant, near San Clemente. Subsequent
historical research was conducted in the early 1970's in connection
with assessing the local tsunami hazard for the design and licencing
of Units 2 and 3 of the same San Onofre Nuclear Power Plant.
Accounts of the 1812
Santa Barbara earthquakes and tsunami waves can be found in numerous
publications, including mission records. Some of the existing
historical descriptions of events which occurred in December
of l8l2 in the Santa Barbara region are presented here to illustrate
the difficulty of analyzing such conflicting historical information
and reaching definite conclusions.
Historical Accounts
of the Effects of the December 1812 Santa Barbara Earthquakes
on the Fransiscan Missions of Southern California
The intensity of the Santa Barbara
earthquake described by Wood and Heck was given as 10 on the
Rossi/Forel scale of 10 grades and the epicenter of the earthquake
was stated to be in the offshore region in the vicinity of the
Transverse Ranges. In the same publication, the description of
the earthquake effects of the 1812 events are as follows:
"Damage to Santa
Barbara, Ventura, and Northern Los Angeles Counties. The Church
of Purissima Mission was destroyed , together with many mission
buildings. The strong fore-shock at about 10:30 am, which did
alarming damage, caused the people to leave the building, and
undoubtedly saved many lives when the main shock came. There
were no deaths, but some injuries. At Santa Ynez Mission, a corner
of the church fell and many new homes were destroyed. At Santa
Barbara, old mission buildings were severely damaged, and the
church was later rebuilt; some buildings were ruined, and the
remaining structures damaged at the Presidio. At Santa Buena
Ventura Mission, the tower was wrecked and much of the facade
of the church had to be rebuilt. At San Fernando Mission, thirty
beams were used to keep the walls from falling. Strong aftershocks
occurred until February, and lesser shocks continued until April,
1813."
There is no reference
of a tsunami in this entry.
The following account
of the effects of the the Santa Barbara, December 1812 earthquakes
on the California Spanish Missions can be found in Padre Señan's
Biennial Report from Mission San Buenaventura, 1811-1812 (translated
from Spanish). Severe damage from the earthquake was also reported
from Mission Santa Ines, Mission Santa Barbara, the Santa Barbara
Presidio, Mission San Buenaventura (Ventura), and Mission San
Fernando, covering a distance of over 100 miles.
The already severe
conditions have been rendered even more severe by the horrible
temblors and earthquakes that have been experienced in this province
and which will constitute a special epoch in it because of the
great resulting damages. The violence of these occurrences have
been extraordinary.
As a result of the
ruinous events we have to build anew the churches of Missions
San Fernando and Santa Barbara. ... Mission San Gabriel suffered
somewhat. At Missions Santa Ines (Santa Ynez, CA)and San Buenaventura
(Ventura, CA) quite some time will be required to repair the
damage which I consider annoying to describe in detail. Concerning
the last named mission I will say only that the tower partially
fell and that the wall of the sanctuary was cracked from top
to bottom. ...
At Mission Purisima
(Lompoc, CA) the bells rang out without the aid of a bell ringer
and in a few minutes the mission was reduced to rubble and ruin
presenting the picture of a destroyed Jerusalem. With the permission
of the government the mission is to be rebuilt at a place about
a leagueand a fourth distant called Los Berroswhich offers notable
and known advantages.
Earthquake Effects at
Mission La Purisima
The most serious damage
from this earthquake was reported at Mission La Purisima, located
at Lompoc Valley. On December 21, 1812, around 10:00 or 10:15
in the morning, a strong eartquake and ground motions frightened
the mission's residents - - priests, Indians and soldiers-- who
rushed out of the mission buildings. This first shock turned
out to be only a foreshock. Fifteen minutes later, a still stronger
earthquake occurred. The shaking of this second earthquake
was so intense that the mission's church bells rang out. The
adobe walls of the mission buildings were shattered, and in some
instances collapsed, reducing Mission La Purisima to "rubble.
Photograph(1935):
Ruins of Mission La Purisima
Regarding specific
earthquake effects of th 1812 Santa Barbara Earthquake at Mission
La Purisima, Fathers Payéras and Ripoll reported:
The extraordinary
and horrible earthquake, which this Mission suffered on the memorable
day of the glorious Apostle St. Thomas, entirely destroyed the
church and vestry, buried under the walls the various images
and paintings, and ruined the greater part of the furniture.
... Some of the work shops went down ... One hundred houses of
neophyte Indians and the community kitchen, the walls of which
were an adobe and a half thick, and roofed with tiles, have become
inserviceable. The garden walls of adobe, covered with tiles,
have collapsed or threaten to fall. ... Experience may teach
us the best method of constructing other buildings.
In a letter to the
Spanish governor of California, Father Payéras wrote:
We have observed with
sorrow that all of the structures are ruined from the foundations
to the roof: that the church is demolished from the foundation
up: and that neither Fathers, nor soldiers, nor neophytes will
or can, without terror or risk, live in their habitations, which
have partly fallen, are partly out of plumb, and are in many
parts seriously cracked.
According to a report
and letter from Mission La Concepcion Purisima de Maria Santisima,
by Zeyphyrin Engelhardt, Mission Santa Barbara, Santa Barbara,
CA, 1932.
At the time of the
disaster 999 Indians, two Padres, and ahandful of soldiers resided
at Mission La Purisima. These missions were working ranches:
at the time of the earthquake, Mission La Purisima had 4000 cattle,12000
sheep, 1150 horses, and grew wheat, corn, and beans. The Mission
even had vineyards, from which the good Padres made wine.
Earthquake Effects at
Presidio Santa Barbara 
The soldiers at the presidio
in Santa Barbara were so disturbed by the earthquake that they
abandoned the presidio, building thatched huts near the Santa
Barbara Mission, where the shaking from the earthquakes was said
to be more moderate. Strong earthquakes continued to rock the
region through February of 1813. The Spanish soldiers from the
presidio did not return to their former home until March, almost
three months after the first earthquake. (Photograph: Santa Barbara Mission presently)
(PARENTHETICAL NOTES:
Repairs to the Missions made subsequently to the 1812 Earthquakes:
The church at Mission Santa Barbara was rebuilt with thicker
walls and was completed in 1820. The church was damaged again
in the 1925 earthquake and repaired . The San Fernando Mission
was repaired, but destroyed by the February 9, 1971, San Fernando
earthquake. It has also been rebuilt. Mission La Purisima was
moved from its original site in Lompoc, California to a site
a few miles away. This mission is now a California historical
monument and is preserved roughly as it appeared around 1820
(see photo above). The earthquake damages at Mission San Gabriel
could not have been too much of a surprise to the Spanish--the
full name of that mission is Mission San Gabriel de los Temblores,
or Saint Gabriel's Mission of the Earthquakes - a name quite
appropriately given)
Historical Accounts
with Reference to the December 1812 Tsunami Waves
The following account of the
1812 tsunami is being quoted from a 1961 revised edition of the
publication entitled "Earthquake History of the United States:
Part II, Stronger Earthquakes of California and Western Nevada,"
by H.O. Wood and N.H. Heck, originally published in 1951.
"This earthquake was associated
with by far the largest seismic sea wave ever reported for one
originating in California. Descriptive accounts indicate that
it may have reached elevations of 15 feet at Gaviota, 30 to 35
feet at Santa Barbara, and 15 feet or more in Ventura. It may
have even shown visible effects in the San Francisco harbor.
"
Reference to Bancroft's
History of California, which has used original mission records,
found in Holden's Catalog of Earthquakes, gives the following
entry regarding the earthquake and tsunami of December 21, 1812,
with the following item on the tsunami stated as follows:
"P. Gil reported
that there was a huge earthquake wave at sea. A stick with a
pendant ball was set up at the mission (Santa Barbara), and that
the ball vibrated continuously for eight days, and later at intervals
for fifteen days. A ship at Refugio was carried up a canyon by
the wave and returned to the sea. "
According to Bancroft's
History of California, P. Gill was in charge of Mission Santa
Barbara until 1813, and according to the records, he was born
on May 1, 1773 and died December 1833.
An item in a San Francisco
newspaper stated that:
"Senora Juana Priones
relates that in 1812, the earthquakes were so severe as to cause
tidal waves which covered the ground where the plaza now is.
"
Also, under the heading,
"1812 September, October, or December ? Sunday? " appears
a report credited to J.B. Trask's register of earthquakes in
California from 1800 to 1863, stating :
"A Spanish ship
anchored 38 miles from Santa Barbara was injured by the shock.
"
Tsunami Effects at Gaviota
Canyon
Gaviota Canyon is not far from
Lompoc, California. It is located at the northwestern end of
the Santa Barbara Channel. At the time of the 1812 earthquakes,
the coast along the northwestern shore of the Santa Barbara Channel
was part of the Rancho del Refugio, a tract of ranch land that
had been given to the first commandante of the Santa Barbara
Presidio, upon the commandante's retirement. It was a favorite
place for American smugglers to trade their goods for otter pelts.
These American smuggling ships traveled between the Spanish-controlled
coast of southern and central California, the Russian-controlled
coasts of Alaska and northern California, and the Hawaiian Islands
(then known as the Sandwich Islands).
There is a report
of a tsunami at Gaviota Canyon (San Francisco Bulletin, March
16, 1864)
A Boston ship, the
Thomas Newland, known before as the Charon, commanded by Capt.
Isaac Whittemore, was lying off anchorage, not far from the Gaviota
Pass, Santa Barbara County, when the sea was seen to retire all
at once and return in an immense wave, which came roaring and
plunging back, tearing over the beach fit to crack everything
to pieces. This wave penetrated the low lands of the gulches
a mile from the shore, forming one of the most terrific sights
possible to conceive. That old ship, then under the name Charon,
afterwards got 1,800 otter skins to the Sandwich Islands (Hawaiian
Islands), and landed them, too; but a few days afterwards she
was captured by the English man-o-war Cherub and taken as a prize
to London.
The 1812 Earthquake
and Tsunami at Santa Rosa Island
One of the last outposts for
the Chumash Indians was Santa Rosa Island which the Chumash called
Mascui. At the time of the 1812 earthquakes, the Franciscan priests
were trying to convince the remaining Chumash Indians to relocate
to the missions on the mainland. When the 1812 tsunami at Santa
Rosa caused the waters to recede several hundred yards from the
island, the Indians became fearful that the island was about
to be engulfed, so they abandoned totally their villages. They
rowed out to in their oceangoing canoes to the mainland and settled
in bands of three or four hundred at the several missions in
the area. The Chumash Indians who moved to the missions did not
fare well, many of them succumbing to European diseases. (H.
W. Henshaw, quoted in Anthropological Records, California Linguistic
Records, v. 15, no. 2)
Conflicts of Historical
Accounts on the Tsunami Event(s)
Obviously, there was some confusion
in the literature about the dating of the 1812 earthquakes, but
it is assumed that this account relates to the December 21, 1812,
earthquake. Another interesting account of the 1812 tsunami appears
in a 1921 paper entitled, "Early Records of Earthquakes
in Southern California" by Ford A. Carpenter, which had
been compiled from the records of the "mission fathers"
and from Englehardt's Franciscans in California. This paper gives
a lengthy account of the 1812 earthquakes in Southern California
with one item of interest, related to San Buenaventura, during
the earthquake of December 21;
"The whole mission
site appeared to settle, and the fear of being engulfed by the
sea, drove all away to San Joaquin in Santa Anna, where they
remained until April, 1813. "
Another account in
a 1960 paper, "California Earthquakes" by Harry O.
Wood states that;
"The sea wave
at Refugio and the strong shock experienced by the ship 38 miles
from Santa Barbara point emphatically to an earthquake of great
energy having a submarine origin. "
There is also another
item dated 1812, in the San Francisco papers relating to the
origin of the earthquake and the tsunami. It reads:
"Severe shocks
with tidal waves. Tidal waves from the great shock in the south
entered San Francisco Bay, and washed over the sides of the plaza
at Point Arena. The San Joaquin segment of the San Andreas Fault,
or the Hayward Fault are the more probable places of origin for
these earthquakes. Mention of tidal waves makes the San Andreas
Fault the more probable source in this instance. "
If this is true or
not, is not known, but it is doubtful that the earthquake that
produced the largest tsunami in California had its origin on
land where the Hayward Fault was. Suggestions have been made
in the literature that this is a possibly mislocated report of
December 21 waves at Santa Barbara, while others have claimed
that the waves observed in 1812 in San Francisco originated from
a different quake on a fault across the San Francisco Bay.
Review of additional
references shows extensive descriptions of the earthquake of
1812 at Santa Barbara, but little information relating to the
tsunami. Various references and accounts of these events can
be found, but these descriptions are somewhat unclear as to the
size of the tsunami in Southern California. Bancroft's History
of California documents the 1812 - 1813 and the 1956 translation
of the manuscript of Angustias De Li Guerra Ord, entitled "Occurrences
in Hispanic California as related by Mrs. James L. Ord to Thomas
Savage for the H. Bancroft Collection in 1878." Mrs. Ord
was the daughter of Don Jose De La Guerray Norieja, who replaced
Jose Arguello as Commandant of Santa Barbara Presidio in the
autumn of 1815. She had been borne on the 11th of June of the
same year. In this account she relates:
"When I went
to the north in 1833, several of the northern missions were in
charge of Fernandinos namely, San Louis Obisbo and Padre Louis
Gil Taboada ( a Mexican by birth, but very Spanish in sentiments).
In speaking to Padre Louis Gil Toboada, he told me that in 1812
there had been very strong earthquakes at Santa Barbara while
he was there. That on the eighth of December while at the Presidio,
there occurred an earthquake so violent that the sea receded
and rose like a high mountain. He, with all the people of the
Presidio, went running to the mission chanting supplications
to the virgin. I asked him humorously, why he had not gone to
see if there was a ship at the foot of the mountain of water.
He also assured me that they had placed a pole with the ball
to it. It was fastened to the ground where the air would not
move it, and it was in continuous motion for eight days. After
eight days the ball was still for two or three hours and then
started to move again, and this lasted for about 15 days. "
Obviously, this account
throws more confusion because the date is given as 8 th December.
This account would indicate that two major earthquakes occurred
on 8 and 21 December, both producing large tsunamis.
John Boardman Trask,
a medical doctor, who was appointed President of the California
Academy of Sciences in 1864, gave the following description of
the tsunami at Santa Barbara in a paper he presented on the history
of the 1812 earthquake as obtained from accounts of native inhabitants
of the coast.
" The sea was
observed to recede from the shore during the continuance of the
shocks, and left the latter dry for a considerable distance,
when it returned in five or six heavy rollers, which overflowed
the plain on which Santa Barbara is built. Inhabitants saw the
recession of the sea and, being aware of the danger on its return,
fled to the adjoining hills near the town to escape the probable
deluge. The sea on its return flowed inland a little more than
a half of a mile, and reached the lower part of town, doing but
trifling damage destroying three small adobe buildings."
In the same paper,
Trask, making reference to a writer unknown to him, quotes him
and adds this account.
" The sea was
seen to retire all at once, and return in an immense wave, which
came roaring and plunging back over the beach. This wave penetrated
the lowlands and gulches a mile from the shore, forming one of
the most terrific sights possible to conceive. "
Conclusions
It is obvious from
these accounts that one, and possibly two large tsunamis were
generated from two major earthquakes in the Santa Barbara region
in December of 1812. The size of these tsunamis may never be
known with certainty, but the estimates of 15 feet at Gaviota,
30-35 feet at Santa Barbara, and 15 feet or more at Ventura,
seem somewhat exaggerated. Which of the two earthquakes produced
the bigger tsunami, or whether indeed there were two separate
events, may never be known with certainty, as all the historical
accounts are sketchy and ambiguous.
Major faults
of the San Andreas fault zone, although capable of strong earthquakes,
cannot generate any significant tsunamis. Only earthquakes in
the Transverse Ranges, specifically the seaward extensions in
the Santa Barbara Channel and offshore area from Point Arguello,
can generate local tsunamis of any significance. The reason for
this may be that earthquakes occurring in these regions result
in a significant vertical displacement of the crust along these
faults. Such tectonic displacements are necessary for tsunami
generation. The area offshore of Point Arguello has sea-floor
features which suggest such displacements, so local tsunamis
from this area as well as in Santa Barbara, can be expected in
the future.
ADDITIONAL REFERENCES
IIDA, K., D.C. Cox,
and Pararas--Carayannis, George, 1967.
Preliminary Catalog
of Tsunamis Occurring in the Pacific Ocean. Data Report No. 5. Honolulu: Hawaii Inst.Geophys.Aug.
1967.
PARARAS-CARAYANNIS
George, THE BIG ONE (from a Book in Preparation
- and Unpublished Reports on the San Onofre Nuclear Plant)
PARARAS-CARAYANNIS
George. American
National Standard:Tsunami Guidelines at Power Reactor Sites, American Nuclear Society, Nuclear
Power Engineering Committee, Working Group 2, April 1974.
PADRE José
Señan, O.F.M., The
Biennial Report from Mission San Buenaventura, 1811-1812, translated by Maynard Geiger,
O.F.M., Old Mission, Santa Barbara, California, 1974.
HENSHAW, H. W. Anthropological
Records, California Linguistic Records, v. 15, no. 2.
CARPENTER Ford A.
1921, "Early
Records of Earthquakes in Southern California" (Paper compiled from the records
of the "mission fathers" and from Englehardt's Franciscans
in California) (No complete citation available).
See also: A Brief History
of California
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