— JACOB NAYLOR
Night manager, Joshua Tree Inn
THE QUAKE jolted gamblers out of bed in Las Vegas and shook buildings as far away as Phoenix. Up to 90,000 utility customers lost power, mobile homes were knocked off pilings in the desert community of Ludlow and a highway bridge was cracked.
But the 2:46 a.m. earthquake caused little more than incidental damage in the huge population centers to the west and south.
“Did you ever play a pinball machine and see the ball get stuck in there and go bam-bam-bam-bam-bam-bam? It just threw my body back and forth as I ran down the hallway,” Dick Dale said from his home 30 miles from the epicenter.
Amtrak’s Southwest Chief en route from Chicago to Los Angeles derailed in the Mojave Desert near Ludlow, more than 125 miles northeast of Los Angeles. The passenger cars remained upright.
Four of the 155 passengers on the 25-car train suffered minor injuries. Twenty-one cars jumped the tracks.
“I was sleeping. It felt like the train jumped off the track ... and I fell out of bed,” said passenger Colleen Broome, who suffered a separated shoulder.
Report from NBC affiliate KNSD in San Diego
from
fault lines to seismographs to damage estimations.
Sources: U.S. Geological Survey, National Earthquake Information Center, Federal Emergency Management Agency
";
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"What is a fault?","What are the basic types of earthquakes?","Are earthquakes really on the increase?","What is the hypocenter?","What is the epicenter?","How many earthquakes are reported yearly?","Earthquake frequency worldwide:","What is the Richter Scale?","What is the Modified Mercalli Scale?","How can I prepare for an earthquake?","Damage of recent earthquakes in the U.S.:"); swaptext = new Array();
swaptext[0]="An earthquake is caused by a sudden slip on a fault and it occurs when plates grind and scrape against each other. Stresses in the earth's outer layer push the sides of the fault together. Stress builds up and the rocks slips suddenly, releasing energy in waves that travel through the rock to cause the shaking that we feel during an earthquake."; swaptext[1]="A fault is a thin zone of crushed rock between two blocks of rock, and can be any length, from centimeters to thousands of kilometers. It is a fracture in the crust of the earth along which rocks on one side have moved relative to those on the other side. Most faults are the result of repeated displacements over a long period of time."; swaptext[2]="The two basic types:
In the last 20 years more earthquakes are noticed yearly because of the increase in the number of seismograph stations in the world and improved global communications. This increase has helped seismological centers to locate many small earthquakes which were undetected in earlier years. "; swaptext[4]="The hypocenter is the point where the earthquake rupture begins, usually deep down on the fault."; swaptext[5]="The epicenter is the point on the surface directly above the hypocenter."; swaptext[6]="The National Earthquake Information Center now locates about 12,000 to 14,000 earthquakes worldwide each year, or 35 a day on average."; swaptext[7]="
| Frequency of Earthquakes Worldwide | ||
| Description | Magnitude | Annual Average |
| Great | 8 or higher | 1 |
| Major | 7 - 7.9 | 18 |
| Strong | 6 - 6.9 | 120 |
| Moderate | 5 - 5.9 | 800 |
| Light | 4 - 4.9 | 6,200 |
| Minor | 3 - 3.9 | 49,000 |
| Very Minor | 1 - 3 | 9,000 (daily) |
swaptext[8]="The Richter Scale is used to measure the magnitude of earthquakes, as determined by seismograph measurements of the height of ground oscillations during an earthquake.
A Twentynine Palms supermarket had structural and water damage, a tree fell on a trailer home and there were several natural gas leaks, said Fire Chief Wayne Eder.
Because the scale is based on a logarithm, every whole-number step in the scale represents about 31 times more energy than the amount represented by the preceding whole number value. The Richter scale has no upper limit; the largest known earthquakes have magnitudes in the 8.8 to 8.9 range.";
swaptext[9]="The Modified Mercalli Scale measures the intensity of an earthquake; in other words, the effect of the earthquake on the Earth's surface. This scale is composed of 12 increasing levels of intensity that range from imperceptible shaking to catastrophic destruction, and is designated by Roman numerals. The scale does not have a mathematical basis; instead it is an arbitrary ranking based on observed effects."; swaptext[10]="
Loma Prieta Earthquake (south of San Francisco)
> “Twelve guests, all definitely >awake. A couple in from Holland, definitely shocked. A >couple in from the U.K. asked me, ‘Is this >normal?”’ Naylor said. “They’re all >taking it rather well, kind of excited. Vacationers, new >experiences, what can I say?”
> Gerri Hagman, owner of the Homestead Inn in >Twentynine Palms, near the epicenter, said she had a lot of >broken dishes and things thrown off shelves, but >couldn’t see any structural damage.
> “I’m a native Californian and >I’ve been in a lot of them; this was a >whopper,” Ms. Hagman said.
Water and gas lines also broke at the Marine Corps Air-Ground Combat Center in Twentynine Palms, but no injuries or major damage were reported, said Gunnery Sgt. Leah Gonzalez.
On Jan. 17, 1994, a 6.7-magnitude quake struck the Northridge area of Los Angeles, killing 72 people and causing an estimated $40 billion in damage.
“The level of shaking is comparable to what was experienced in Northridge,” said Lucy Jones, a seismologist with U.S. Geological Survey at Caltech. “The good news is that there are fewer people out there.”