Epicenter is 1km South of View Park-Windsor Hills, CA – near Inglewood / Hawthorne
M 3.7 – 1km S of View Park-Windsor Hills, CA
A noticeable, strong tremor for millions of quarantined residents was felt in the west central area of LA at around 12:03 AM on April 22, 2020. Although, at 3.7 magnitude, it was not a serious, dangerous quake the location, being in the urban west side of the city would be concerning if a larger after shock were to follow. Or, if this was a precursor to a larger quake to come.
Earthquakes with magnitudes between 3.0 and 4.0 occur on average five times per year in the greater Los Angeles area, according to a three-year data sample.
Naturally with the city still in the grips of a novel coronavirus lockdown, the last thing people need is any additional reason for concerns.
80,000 Small Quakes have moved the fault line 0.8 inches since July 5th Quake…
On Wednesday, November 13th at 11:26 a.m., an earthquake with a magnitude of 3.9 and a depth of 5.7 miles was reported 12 miles away from Ridgecrest, California. Interestingly, this earthquake is located at the same epicenter as the record-breaking 6.1 magnitude and 7.1 magnitude earthquakes that occurred on July 4th and 5th, respectively.
A closer look at the big July earthquake that occurred on Independence Day reveals that it appears to have activated the Garlock fault. The fault line is 185 miles long and runs from a junction with the San Andreas fault at Antelope Valley and has largely been inactive for the past 500-years. However since the July quakes, Ridgecrest has felt more than 80,000 earthquakes, most of them too low on the richter scale to warrant news coverage, resulting from the Garlock fault’s movement.
“The fact that the Ridgecrest rupture terminated right next to the Garlock is what cased this behavior.”
Zachary Ross, Assistant Professor of Geophysics at Caltech
However, generally, such movement should not cause immediate alarm as it’s quite common for faults to shift after a big earthquake. A “trigger slip” is where an earthquake is triggered by a previous quake – in this case, according to seismologists, today’s quake may have been a “passive response” to the Magnitude 7.1 earthquake, 11 miles from Ridgecrest, CA at 8:19 PM.
“The fact that we have a trigger slip after a 7 [magnitude earthquake] is really common. It’s like a passive response to the energy being released by the big earthquake”
The best policy is not to be Alarmed but to stay Prepared
In early October, Time magazine published a report citing scientific study, by researchers from the California Institute of Technology and NASA’s Jet Propulsion Laboratory, where it was indicated that the movement along the Garlock fault could indicate a possible increase in seismic activity, and that the fault was capable of producing an 8.0 magnitude earthquake at some point, although there is no way to predict when.
Earthquakes with a 3.0 magnitude or more were reported to have had an epicenter near the Ridgecrest fault in the last ten days. With a recent three-year data sample as a reference, 234 earthquakes on average happen every year in California and Nevada with 3.0 to 4.0 magnitudes. It is important to bear in mind that each whole number on the Richter scale is exponentially stronger than the previous whole number (an 8.0 is 33 times stronger than a 7.0 but a 9.0 is, yikes, 1,089 times stronger – arrived at by multiplying 33×33).
Although this earthquake, at 3.9 was at a magnitude that is common and not powerful enough to do damage, the fact is that Southern California is home to highly vulnerable fault lines and a quake measuring 8.0 or higher is going to happen at some point, it is only a question of when. Therefore it is highly advisable to prepare for any earthquake-induced emergencies that may happen now, and your chance of avoiding any negative effects will be far higher in the event that “the big one” happens anytime soon.
At ELEVEN times the strength of the temblor on July 4th, just one day earlier, Friday’s earthquake has all of Southern California thinking about the next one…
Living in Southern California we all know that earthquakes can happen at anytime. As a matter of fact, small shocks happen all day, everyday. Every year California experiences around 10,000 tremors, most of them small. Perhaps around 100 per year are above 3.0 and fifteen to twenty are above 4.0.
It is also important to understand how the size and strength of quakes are measured. The richter scale, once used to measure the strength of earthquakes, has now mostly been superseded by the Moment Magnitude scale (Mw), which measures an earthquake of Mw 7.0 at 1000 times as much energy as one of 5.0 and about 32 times that of 6.0.
Another example would be: A magnitude 8.7 earthquake is 23,000 times stronger than a magnitude 5.8 earthquake. This massive difference in strength (as opposed to size, which is measured differently) is the reason why anything above 7.0 is very serious and can do great damage if in a highly populated area, while an 8.0, for example, could be catastrophic.
Now That We Have Your Attention: Some Earthquake Preparedness Advice
Many simple things can help to reduce any possible damage to your home or, more importantly, harm to yourself and your loved ones.
Photo / Adobe
Just as you wouldn’t want a bookshelf to accidentally fall on your baby, in an earthquake, furniture and especially appliances can be dangerous to anyone in the house.
Prepare for an earthquake in advance by using “baby-straps” that can be purchased at any hardware outlet, and use them to secure shelves, televisions and appliances like microwaves. People can be injured or even killed by these heavy objects in a severe quake.
Making sure your bed is not near any windows can help avoid broken glass. Use picture frames with clear plastic instead of glass in halls and stairways to make sure your exit route will be safe.
At least a few fire extinguishers should be ready in known locations around the house. As you can imagine, emergency lights in the bedroom and in various other places are essential. These can be battery powered, emergency crank, or even solar as long as they store a charge, in case the quake hits at night, or power is out for days, or even weeks.
And, while we are on the subject of electricity, if services are interrupted in your area, many things we rely on daily will also potentially be unavailable. Gas pumps need power, so it is always smart to keep at least one vehicle with the tank at more than half full.
“The real trick is: do these things now, don’t get caught wishing you had.”
– K.L.
Gas water heaters or any propane tanks are also potentially dangerous. Your gas heater or water heater must also be secured. An automatic valve that will sense any vibration beyond a certain threshold will help prevent fires that can be caused when an active gas line breaks during an earthquake.
Photo / Adobe
At minimum, be sure to know how to manually shut off your gas. This is usually done with a wrench, or a tool can be attached to the valve area to be sure you have it handy.
Keep some spare shoes near the bed to slip on, in case you awaken to debris and even broken glass. Cell phone service might be out, but even if it is working you will need charged phones. Cell battery back-ups are cheap these days and can be a life saver. For longer outages, if you do not have a generator, even a solar / emergency crank phone – a usb charger which is rechargeable by solar and hand crank can be great.
As can be seen by the common sense tips listed so far, much of these ideas can be thought of by just imagining what the situation could be like in the direct aftermath of an earthquake. The real trick is: do these things now, don’t get caught wishing you had.
Here are a few more tips:
Download maps in .pdf format and store on a laptop (keep it charged). Or just get some of those old fashioned paper maps.
Learn CPR: go to a class and be the one ready to save those around you.
For homeowners: check the structural integrity of your foundation. Double-check your earthquake insurance policy.
Keep extra water (lots of it) in your home as well as food and other supplies such as medicine, first aid kit and other essentials. Keep empty, safe water containers around to fill for extra H2O. Enough for at least a week or two is advised
Be sure that there is some cash hidden for this occasion; ATM machines can also be out for extended periods after a very large temblor.
If you implement the majority of the various suggestions described above, you are way ahead of most, and have much better chances of survival in the event of an earthquake emergency.
What to do immediately after a quake:
To panic or to rush is always dangerous. You can’t outrun an earthquake. If you are in public, such as at a movie theater, concert or sporting event, get down onto the floor and protect your head and upper body.
If in a large building, drop and cover, under a sturdy desk or table and hold on until the shaking stops. Stay away from windows and elevators.
When you are already outdoors, or if you can easily reach an open area, if it is safe to get there, stay away from anything that could cause harm – power-lines, billboards, buildings, even cars and trucks.
If near the ocean and the quake has a large enough magnitude to cause significant damage on land, a tsunami is a real possibility. Get to high ground, further inland, 2 miles or more. Driving is unlikely to be feasible, so hike to a spot more than 100 feet above sea level.
A large rolling earthquake centered 11 miles from Ridgecrest, CA. at 8:19 PM, was felt all the way to Mexico. The epicenter was again in the same relatively remote area as the July 4th quake: approximately 100 miles from downtown Los Angeles, in San Bernardino County.
In our newsroom, near LAX, the walls swayed and it was as if we were on a ship. Having been in the same location during the July 4th quake I can say that the difference was that this one lasted about twice as long. It was immediately clear that it was a higher magnitude.
For us near the coast, it is fortunate that the epicenter was approximately the same as the last one – approximately 150 miles inland
