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“ WHY IS LOS ANGELES TICKING?”

IT’S ALL OUR FAULT, BUT IT’S

O. K.!

Ó Peter V. Boyd 1997/2011

702-423-6520

This is a revision, consolidation and update of three papers written after the 1994 Northridge Earthquake with additions made after May 2011 and the 8.7 Indonesian and 9.0 Chilean and Japanese quakes and Tsunami. Updated June 1st 2011.

The approach may be a bit circuitous, like the relationship of hidden faultlines, but the focus is always there, beneath the surface. Beneath Los Angeles .

* “It’s all our Fault, but it’s Alright!” about the types of faultlines in Southern California.

* “Southern California Chronology 1000 AD – 1993 AD ” About the physical and societal chronology of the state, with emphasis on the Los Angeles area. In this paper only some of the geologic elements are included.

* “Why is Los Angeles Ticking” About the perils of poor building design and construction, the lack of adequate brush clearance in our fire prone environment and some of the other areas that could lead to social and economic disaster.

Seeing the experience of the Japanese trifecta of earthquake, tsunami and nuclear disaster, the likelihood of Los Angeles’ level of peril is highly elevated.

Much of this was written in 1996 but it has been consolidated, revised and updated because nothing has changed, only that much more information is available and that certain theories have been proven correct.

The 2011 Earthquake and Tsunami in Japan only emphasizes the same points as they apply to the west coast of the United States . It only underscores the same principals and problems that existed then and, without any clear corrective measures, are even more perilous today.

The largest recorded earthquake in the United States struck Prince William Sound in Alaska on March 28^th, 1964 , It was on Good Friday. Its magnitude was 9.2.

That’s 20 times as strong as the 2011 Japan quake.

Each year Southern California has around 10,000 earthquakes. Only a few hundred are over 3.0 and 15 to 20 are over 4.o.

On September 9^th, 2001, there was a 4.2 magnitude centered in West Hollywood.

On March 16^th 2010, there was a 4.4 magnitude centered in Pico-Rivera, three miles SSW of Whittier Narrows. Both earthquakes, though small, are in trigger zones for more seismic activity.

LET’S START WITH SOME DEFINITIONS

Words like: Magnitude. Richter Scale. Mercalli Scale. Momentary Magnitude. Focus. Epicenter and a few others that will pop up, so to speak, like Blind Thrust Fault. Slip Fault. Tectonic Plates. Subduction Zones, etc.

Some will appear in new sections, with explanation.

Much of the use of the term “Richter Scale” is a way of placating the public’s and the journalists’ desire to put labels on complex phenomena.

In the 1930’s the Japanese were in the lead in earthquake research, partly due to the trauma of the 1923 Tokyo quake. At that time Seismologist KiyooWadati publicized a method that assigned numbers to the magnitude of shockwaves using a system of monitoring sensing station’s readings and factoring them by the distance from the event. This produced communicable numbers to describe the event.

In 1935 Richter adapted Wadati’s work to a simple numeric scale that was in some ways based on the stellar scales that were in use by astronomers at Cal Tech at that time. He gave it a logarithmic scale to the power of 10, also an adaptation from astronomy, and with several revisions for distance and other variables, it provided communicable concepts to a mass audience.

“(Richter) introduced it (the scale) because he was tired of the newsman asking him about the relative size of earthquakes.” says seismologist Bruce Bolt of Cal Berkeley.

In the 1970’s, Hiroo Kanimori, a successor to Richter at Cal Tech, and a team of others, devised a far more complex and accurate system of scales that describe the event.

MESUREMENT OF EARTHQUAKE OBSERVATIONS - SINCE 1900

DISCRIPTOR MAGNITUDE ANNUAL AVERAGE:

GREAT : 8 AND HIGHER. 1 event was claimed in 1994, (Although now over four events have occurred between 1970 and 2011 in Chile, Alaska and Japan.)

MAJOR : 7 - 7.9 18 events.

STRONG: 6 - 6.9. 120 events.

MODERATE: 5 - 5.9. 800 events.

LIGHT: 4 - 4.9. 6,200 estimated events.

MINOR: 3 - 3.9. 49,000 estimated events.

VERY MINOR: Less than 2 - 2.9. 1,000 estimated events per day.

MAGNATUDE 1.0 – 1.9: 8,000 estimated events per day.

QUAKES AND THEIR MAGNITUDE –ENERGY RELEASE EQUIVALENT IN MILLIONS OF ERGS

-2 = 630. THE ENERGY OF A 100 WATT BULB LEFT ON FOR A WEEK

0 = 630,000. THE ENERGY OF A 1 TON CAR @ 20 M.P.H.

2 = 630,000,000. THE ENERGY OF A LIGHTNING BOLT

4 = 630,000,000,000. THE SEISMIC ENERGY OF 1 KILOTON OF EXPLOSIVES

6 = 630,000,000,000,000. THE ENERGY OF THE HIROSHIMA ATOMIC BOMB

8 = 630,000,000,000,000,000. THE ENERGY OF THE 1980 MT. ST.HELENS ERUPTION

10 = 630,000,000,000,000,000,000. THE ENERGY OF THE ANNUAL U.S. ENERGY CONSUMPTION (To be added)

There are several types of measurement of Earthquakes. Two popular types, The Richter Scale, still quoted often, was devised by Dr. Charles Richter. It measures Magnitude.

The Richter Scale is being phased out by two scales also using logarithmic points that are similar to the old scale, but keep readings at two points; the Epicenter, the point below the ground at which the Quake originates, and the Focus, the point at the surface where the fissure radiates it’s energy

The name for the newer scale of measurement is The Momentary Magnitude Scale.

The Mercalli Scale measures Intensity. Both the American Military Man, Richter, and the Italian Priest Mercalli, were Seismologists. They were geologists with a specialty. Their disciplines were the study of Earthquakes.

The Richter Scale is a method of computations from specialized Seismographs that assign a number to the Magnitude of the event. “The Richter Scale”, as a descriptor, is on it’s way out.

* ”What’s going on is that we’re just recovering from decades of telling a white lie, that’s all.”

Thomas H. Heaton, President of the Seismological Society of America says, “You probably wouldn’t catch us using the term “Richter Magnitude” around here even though this was the home of Richter.”

Rodger Musson of the British Geological Survey in Edinburgh adds, “It seems to be a popular misconception that it’s actually a piece of equipment, like a bathroom scale. Things have come to such a pass in today’s press, that I had an inquiry recently from the Sunday Times, no less, asking for a picture of the Richter scale. I said this was a bit like asking for a picture of kilometers.”

The terms of measurement in use now are modifications of the numeric environment of the Richter scale, but, in 1995, the “correct” terminology is still in flux. Associated Press has recently dropped “Richter” terminology and now discusses “Momentary Magnitude” and “Preliminary Magnitude.” Because the scales are logarithmic, each Point of Increase is Ten Times the amount of strength.

Thus, a 7.0 is one hundred times the power of a 6.0, and an 8.0 is one thousand times that of a 6.0! We can see that little things mean a lot when we note that a 6.1 is ten times as strong as a 6.0.

THE MERCALLI SCALE

The Mercalli Scale was introduced in 1902. Since then, refinements in practice have resulted in a standard Modified Mercalli Scale based on interviews and effects.

The Scale goes from Roman Numerals One through Twelve.

THE MODIFIED MERCALLI SCALE

l. Not felt, except by a few people under especially favorable conditions.

ll. Felt only by a few people at rest. Delicately suspended objects may swing.

lll. Felt quite noticeably under favorable conditions. Parked automobiles may rock slightly.

lV. Felt by most people; some awakened. Dishes, windows, doors disturbed, walls cracked. Sensation like that of a heavy truck striking a building.

V. Some dishes, windows, and so on, broken; a few instances of cracked plaster; unstable objects moved.

Vl. Felt by all; many frightened and run outdoors. Some heavy furniture moved; a few instances of fallen plaster or cracked chimneys.

Vll. Everyone runs outdoors. Damage negligible in buildings of good design and construction; slight to moderate in well built ordinary structures; some chimneys broken. Noticed by people driving cars.

Vlll. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned. Sand and mud ejected in small amounts.

lX. Buildings shifted off foundations. ground cracked conspicuously. Underground pipes broken.

X. Ground badly cracked, rails bent, landslides considerable from riverbanks and steep slopes. Water splashed over banks.

Xl. Few masonry structures remain standing. Bridges destroyed. Broad fissures in the ground. Earth slumps and land slips in soft ground.

Xll. Damage total.Waves seen on ground surface. Lines of sight and level distorted. Objects thrown into the air.

You can see that this is a subjective way to evaluate the effects of a concrete occurrence. It depends on wide investigation and many interviews, plus first hand observation of the aftermath of the event.

Because there is often discrepancy between the Mercalli rating of effects and the numbers of the Richter readings from the epicenter, a newer method of taking readings from both the Epicenter (The point of fracture below the surface) and the Focus (On the surface above the fracture) is in use.

The place where the Earthquake originates is called the Focus. The point on the ground directly above that is called the Epicenter. In the case of the Northridge / Reseda Quake, the Focus was eleven miles below the Epicenter of Lindley Street and Saticoy.

As a trivia aside, the largest quake ever recorded was a 9.5 in Chile in 1960. Chile is a strong candidate for an offshore quake and Tsunami similar to Japan, 2011, as is the Seattle region.

The weak blind thrust plates, like so many under the Los Angeles Basin, when they are under compression, form a thrust or overlapping sliding sheet. If it thrusts over the opposing sheet, it creates a hill or adds to a hill. If it thrusts under the opposing plate, the ground lowers into a valley effect. Very generally, all areas with hills and valleys are the result of under land tectonics.

The areas north of the San Fernando Valley, Canyon Country, Saugus, Valencia, especially the Vasquez Rocks area, until the flats going to Lancaster, were created by violent quakes in the past. Pretty much everywhere in the world where you see mountains and cliffs rising from a flat plain, plate movement in the distant past created them. From the Rocky Mountains through the Alps, New Zealand and even the Pacific Palisades, it took massive force to raise them and they wear their sharply defined faces with pride.

As I reference later, the Northridge quake raised the Santa Susana Mountains by 18 inches.

Much of the information about the fault systems under Los Angeles, until very recently, have been known and hidden by the oil and natural gas companies. They considered it “Proprietary Material.” Scientists now, in 2011, have access to that information and are adding up the material’s veracity.

The newer Los Angeles faults were identified by Dr. Peter Shearer, a seismologist at the Scripps Institute of Oceanography in San Diego and by Dr. John Shaw, a Structural Geologist at Harvard University .

Dr. Shaw states that the blind thrust faults of Los Angeles are caused by the relative motion of the North American and Pacific plates, two huge masses of crusts that are sliding past each other along the San Andreas Fault. Because of a dogleg in the fault, The Los Angeles basin is being squeezed like an accordion between these masses of earth.

The consensus is that the blind thrust faults under downtown L. A. can, and at some time will, produce a devastating earthquake.

* “This is the first solid proof that one is actually present” and that the newly identified one would measure 250 square miles and is believed to be at least nine miles deep.

Dr. James Dolan - Geology professor at USC.

He was also quoted as saying the newly identified fault is “The poster child of blind thrust faults underneath Los Angeles.”