Felt reports, cont.
Car alarms over a wide area are said to have gone off. Cell phone coverage was immediately jammed and handsets for many local phones were knocked out of their cradles, causing further disruptions with the local phone service.

There are reports of items being knocked from tables and shelves and some commercial damage has occurred.

One report indicated there was a loud boom prior to the shaking.

Many people reported dishes and glassware rattling, pictures on walls shaking and windows vibrating.

Some said they felt an initial jolt (P-wave) followed by a brief pause, then longer shaking (S-wave). Some people near the epicenter said they did not feel the temblor. Many people shopping or visiting in the downtown areas were frightened and quickly left stores and shops. A few were panicked and ran outside.

A few noticed their animals were spooked.

Despite the relative moderate magnitude of the temblor, city and county fire departments went into earthquake emergency modes, pulling their equipment outside of buildings and sending helicopters into the sky to look damage. The only building that sustained any noticeable damage was on Kelton Avenue in Westwood where a wall of glass blocks toppled, leaving someone's home office visible from the street.

Background
The quake occurred close to the surface trace of the well-known Santa Monica-Hollywood thrust fault. Because this fault dips (or is angled) to the north under the Santa Monica Mountains and that the quake triggered at a depth of 3.8 km, it indicates the quake occurred below the Santa Monica-Hollywood thrust fault on some unknown fault.

In addition, Caltech reported the type of fault motion that caused the quake was strike-slip, or side to side. The Santa Monica-Hollywood thrust fault is, obviously, a thrust fault (up and over), thus placing the source for the quake elsewhere.

Therefore, it is likely the quake occurred along a northern trace of the Newport-Inglewood fault zone or a splay there of. Further analysis may help determine the exact fault responsible for the temblor.

The earthquake plots between the San Vicente and Salt Lake oil fields, however, it is not likely that the quake was related to the oil production in the area.

Additional seismic information links:

• Seismo-Watch - links for more Southern California information
• SCSN Recent Earthquakes Page.
• SCSN Recent Earthquakes Page via Northern CA server
• USGS Community Intensity Report

Mainstream media news reports:

• Moderate earthquake shakes Southern California, KNBC-TV 4
• Earthquake Shakes Los Angeles, ABC News
• 4.2 Quake Hits Los Angeles Area, KCBS - Channel 2000
• Earthquake Jolts Los Angeles Area, AP 1
• Small Earthquake Jolts Los Angeles, AP 2
• 4.2 Temblor Jolts Nerves in Southland, LA Times << Best Story