Wednesday, 11 March 2020

Magnitude 5.8 Earthquake off the coast of northern California.

The United States Geological Survey recorded a Magnitude 5.8 Earthquake at a depth of about 3.2 km roughly 69 km off the coast of the city of Eureka in Humboldt County, California, slightly before 8.00 pm local time on Sunday 8 March 2020 (slightly before 3.00 am on Monday 9 March GMT). There are no reports of any damage or injuries relating to this quake, but people have reported feeling it across much of northern California and southern Oregon.

The approximate location of the 8 March 2020 Eureka Earthquake. USGS.

California is extremely prone to Earthquakes due to the presence of the San Andreas Fault, a tectonic plate margin that effectively bisects the state. The west of California, including Santa Barbara and Los Angeles, is located on the Pacific Plate, and is moving to the northwest. The east of California, including Fresno and Bakersfield is on the North American Plate, and is moving to the southeast. The plates do not move smoothly past one-another, but constantly stick together then break apart as the pressure builds up. This has led to a network of smaller faults that criss-cross the state, so that Earthquakes can effectively occur anywhere.

However the  8 March 2020 Earthquake happened on the southern part of the Mendocino Fracture Zone, a westward extension of the San Andreas Fault, where the Gorda Plate to the north is movingw westward relative to the Pacific Plate to the south. Along this boundary the rocks of the two plates continuously stick together, then become stressed as the motion of the two plates draws them apart. This stress builds up until the rocks are forcibly snapped apart, which we experience as Earthquakes.

 Map showing the progress of the San Andreas Fault to the north, where it becomes the Gorda Plate subduction zone. Humboldt State University.

The Gorda Plate, along with the Explorer and Juan de Fuca Plates are remnants of an ancient oceanic plate, the Fallaron Plate which has almost completely disappeared beneath North America. The Fallaron Plate formerly diverged from the Pacific Plate along the Fallaron Ridge, but as the plate has been subducted both it and the ridge have broken up. The remnants of the plate are now the Explorer Plate in the north, then the Juan de Fuca Plate, then the Gorda Plate in the south. This borders onto the Pacific Plate along the Mendocino Fracture Zone, which extends on land as the San Andreas Fault.  

 North of California the San Andreas Fault becomes the Mendocino Fracture Zone. USGS.
 
Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) you can report it to the USGS here.

See also...

https://sciencythoughts.blogspot.com/2019/12/urechis-caupo-thousands-of-fat.htmlhttps://sciencythoughts.blogspot.com/2019/11/rockfall-kills-two-climbers-in-sierra.html
https://sciencythoughts.blogspot.com/2019/08/magnitude-590-earthquake-in-inyo-county.htmlhttps://sciencythoughts.blogspot.com/2019/08/rockfall-kills-three-on-californian.html
https://sciencythoughts.blogspot.com/2019/07/second-major-earthquake-hits-kern.htmlhttps://sciencythoughts.blogspot.com/2019/07/magnitude-64-earthquake-in-kern-county.html
Follow Sciency Thoughts on Facebook.

4 comments:

  1. Thank you for sharing
    https://aab-edu.net/

    ReplyDelete
    Replies
    1. Hello everyone..Welcome to my free masterclass strategy where i teach experience and inexperience traders the secret behind a successful trade.And how to be profitable in trading I will also teach you how to make a profit of $12,000 USD weekly and how to get back all your lost funds feel free to email me on( brucedavid004@gmail.com ) or whataspp number is +22999290178  



























      Hello everyone..Welcome to my free masterclass strategy where i teach experience and inexperience traders the secret behind a successful trade.And how to be profitable in trading I will also teach you how to make a profit of $12,000 USD weekly and how to get back all your lost funds feel free to email me on( brucedavid004@gmail.com ) or whataspp number is +22999290178  

      Delete
  2. I was diagnosed of herpes virus, I have tried all possible means to get cure but all my effort proved abortive, until a friend of mine introduced me to a herbal doctor called Chief Dr Lucky, who prepare herbal medicine to cure all kind of diseases including herpes virus (Herpes), when i contacted this herbal doctor via email, he sent me herpes virus herbal medicine via courier service, when i received the herbal medicine he gave me step by step instructions on how to apply it, when i applied it as instructed i was totally cured from the virus within 3 weeks of usage. Contact this great herbal doctor today to get your cure. 
    Via Email : chiefdrlucky@gmail.com
    Whats App : +2348132777335
    website : http://chiefdrluckysolutionhome.website2.me/    

    ReplyDelete
  3. I Want To Appreciate Dr.OYAGU for hs great deeds, I Was Diagnosed With type 2 Herpes Virus Last year,And Was Look For Solution To Be Cured Luckily I Saw Testimonies On How Dr.OYAGU Cure Herpes Virus I Decided To Contact Dr.OYAGU I Contacted Him He Prepared A Herbal Medicine Portion And Sent It To Me,I Started The Herbal Medicine For My Health.He Gave Me Step By Step Instructions On How To Apply It, When I Applied It As Instructed, I Was Cured Of This Deadly Herpes Within 2 weeks, I Am Now Herpes Negative.My Brother And Sister I No That There Are So Many People That Have There Same Herpes Virus Please contact Dr OYAGU To Help You Too,And Help Me To Thank Dr.OYAGU For Cure Me, I’m Cured By Dr. OYAGU Herbal Medicine,His Contact Email:oyaguherbalhome@gmail.com

    Or Cell Whatsapp Number +2348101755322 thank you

    ReplyDelete