Exceptionally strong shallow earthquake along the border of Nevada and California

Update 22:50 UTC : - The aftershocks are continuing at a high frequency. The latest was a M4.0. All the epicenters are concentrated in a very narrow area.
- Concerning Mammoth Mountain volcanic field and the Nevada earthquakes, Rodger Wilson (writer of our Daily Volcano reports) is  convinced that this swarm (actually an aftershock sequence) is not related (by any direct means at least!) to magmatic activity in the Long Valley region. As for the Basin and Range, a lot of seismicity there does include magma, or at least movement of magmatic fluids at depth, but until he sees the swarm greatly intensify (and shallow!), the relation with volcanic activity does not exist.

Update 09:12 UTC : Earthquakes and (expected) shaking intensities are not an exact science as you can see by comparing both images below. The population exposure is the theoretical map of the intensities as expected by USGS. Mammoth Lakes and Bishop are just falling in the MMI II radius (very weak shaking), which should have been hardly felt in these towns. But ... people have felt this earthquake in a far wider radius (map just below this paragraph). Such maps are mainly an indication on what to expect in general. Do not blame USGS to be erroneous, because seismology (including intensities) is a very complicated matter. Earthquake waves are propagated through many layers in the earth and each layer can have a different propagation structure. We can assure you, USGS does great work in getting as close as possible to the reality and their work and accuracy are improving year after year.

Screen Shot 2013-02-13 at 10.03.14

Update 08:47 UTC : Since the mainshock we have counted 8 M3+ aftershocks. Aftershocks are normal and some faulting areas are very sensitive to aftershocks like this one.
- 28000 people will have experienced this as a weak earthquake. These are theoretical intensity values. As one can see below in our I Have Felt It reports, this earthquake was perceived by people at a far greater distance than the USGS did expect.

Exceptionally strong earthquake in a luckily sparsely populated area.
The maximum shaking intensity as calculated by the USGS was a weak to very weak shaking (MMI II or III).
The area has however a number of cattle barns in a radius of 10 to 20 miles from the epicenter and it cannot be excluded that these may have been damaged.
The epicenter area has NO volcanic past but influencing the seismic pattern of the nearby Mammoth Mountain volcanic field cannot be excluded.

Nevada shaking map February 12 2013

Most important Earthquake Data:

Magnitude : 5.1

Local Time (conversion only below land) : 2013-02-12 16:10:13

GMT/UTC Time : 2013-02-13 00:10:13

Depth (Hypocenter)  : 12.4 km

Depth and Magnitude updates in the list below.

Share your earthquake experience (I Have Felt It) with our readers.
Click on the "I Felt It" button behind the corresponding earthquake. Your earthquake experience is not only important for science, but also for people in the area as well as our global readership.

SRC Location UTC Date/time M D INFO
USGS Nevada Feb 13 22:20 3.8 11 MAP I Felt It INFO
USGS Nevada Feb 13 18:18 2.5 8 MAP I Felt It
USGS Nevada Feb 13 18:12 2.5 8 MAP I Felt It
USGS Nevada Feb 13 18:06 2.5 6 MAP I Felt It
USGS Nevada Feb 13 17:05 3.5 8 MAP I Felt It INFO
USGS Nevada Feb 13 14:17 2.5 3 MAP I Felt It
USGS Nevada Feb 13 10:03 2.5 4 MAP I Felt It
USGS Nevada Feb 13 09:53 4.0 5 MAP I Felt It INFO
USGS Nevada Feb 13 05:38 3.6 7 MAP I Felt It INFO
USGS Nevada Feb 13 05:10 2.6 8 MAP I Felt It
USGS Nevada Feb 13 03:16 3.2 7 MAP I Felt It
USGS Nevada Feb 13 03:07 3.5 8 MAP I Felt It
USGS Nevada Feb 13 02:59 3.7 8 MAP I Felt It
USGS Nevada Feb 13 02:58 3.4 5 MAP I Felt It INFO
USGS Nevada Feb 13 02:04 2.6 7 MAP I Felt It
USGS Nevada Feb 13 01:56 2.5 8 MAP I Felt It
USGS Nevada Feb 13 00:49 3.7 4 MAP I Felt It INFO
USGS Nevada Feb 13 00:49 3.7 4 MAP I Felt It
USGS Nevada Feb 13 00:44 3.3 8 MAP I Felt It
USGS Nevada Feb 13 00:39 3.3 8 MAP I Felt It
USGS Nevada Feb 13 00:17 2.7 10 MAP I Felt It
EMSC Nevada Feb 13 00:10 5.1 12 MAP I Felt It
GEOFON California-nevada Border Region Feb 13 00:10 5.1 10 MAP I Felt It
USGS Nevada Feb 13 00:10 5.1 12 MAP I Felt It INFO
  • Citrus Heights, CA - Was getting ready to fall asleep and felt it shaking for about 18 seconds while laying in bed.
  • Sacramento, California - Rolling sensation.
  • Bishop, CA - Started with a light back and forth roll, then slowly rolled a little stronger. Seemed to last about 12 seconds.
  • Folsom, CA - Originally from southern CA and have been through 3 earthquakes including north ridge so I am familiar with them. I work for a large corporation on the fourth floor and felt the floor along with my desk shaking...or I should say swaying back and forth. Interesting as it is the first one I have felt since I arrive in Sacramento 16 yrs ago.
  • Bishop, CA - Rocking motion. Continued for about 30 seconds.
  • Sacramento - I was on the 12th floor of the Wells Fargo building in downtown Sacramento.
  • Fresno, CA - Second floor office. 5 seconds of quick shakes then slow rollers for another 10 seconds. Curtains moving
  • Fresno downtown - In our 8th floor office, we felt a solid wave over just a few seconds. I knew without a doubt we'd just had an earthquake...
  • Sacramento, CA - I felt my chair wobble ever so slightly for maybe a couple of seconds. Oddly, I felt slightly queasy from the experience. I knew instantly it was an earthquake.
  • Sacramento, Capitol Mall - I was in my office leaning up against a cubicle wall talking when I felt the wall shake really quickly. Then it was over. I looked around to see if anyone else felt it. That's when another co-worker open the door and asked if we felt the building shake. Everyone on her end of the building felt the movement. Just as quickly as it happened, it was over.
  • Fresno, CA - I was on the fourth floor of Fresno City Hall. It was more of a rolling sensation rather than shaking.
  • Davis, CA - Sitting on the 3rd floor in Davis, felt the building jolt, asked if anyone felt that? Another co-worker said she did.
  • Rancho Cordova - Was a rolling sensation. I am on the 2nd floor of an insurance company.
  • Shaver Lake, CA - This earthquake was centered in Tonopah, NV near the CA border. Here it was felt as weak but the inside double glass door rattled and it lasted over 10 seconds. Then, it happened again a few seconds later.
  • Downtown Sacramento - I felt it while sitting in my office on the 4th floor working, the blinds started swinging back and forth and the building shaking. No one else in my office seemed to feel it but me.
  • Fallon, NV - Glass doors rattled a bit and definitely felt rumble under my feet.
  • Silver Springs - Felt floor movement and noticed books on upper shelf swaying. Also could hear structure creaking and a single pop sound.
  • Tonopah - I was sitting on my couch then felt the house move, almost like it was being gently pushed back and forth. I have felt these before. This one was mild. Nothing fell and the kids didn't notice it.
  • Lovelock, NV - Sitting at my desk, felt rolling motion for about 30 sec.
  • Roseville California - Sitting at my computer not sure of the exact time but felt my rolling chair wave like a waffle effect from floor.
  • Folsom, CA - Work on the 2nd floor of a large building. Felt the floor shake up and down for several seconds, like someone was driving a cart by my cubical with a heavy load on it. Since there was no such activity I thought it might have been an earthquake.



    Other earlier earthquakes in the greater epicenter area (since 2012)

    Strongest earthquakes Magnitude 3.5 or more within a 150 km radius from this earthquake (max. 60)




    I felt the shaking *
    Country where you felt the earthquake *
    City/Village where you felt the earthquake *
    Street or suburb (area) where you felt the earthquake
    Latitude (area) where you felt the earthquake
    Longitude (area) where you felt the earthquake
    Shaking Strength *
    MMI II (Very weak shaking) ?
    People :
    Felt by persons at rest, on upper floors or favorably placed.
    MMI III (Weak shaking) ?
    People :
    Felt indoors; hanging objects may swing, vibration similar to passing of light trucks, duration may be estimated, may not be recognized as an earthquake.
    MMI IV (Light shaking) ?
    People :
    Generally noticed indoors but not outside. Light sleepers may be awakened. Vibration may be likened to the passing of heavy traffic, or to the jolt of a heavy object falling or striking the building.
    Fittings :
    Doors and windows rattle. Glassware and crockery rattle. Liquids in open vessels may be slightly disturbed. Standing motorcars may rock.
    Structures :
    Walls and frames of buildings, and partitions and suspended ceilings in commercial buildings, may be heard to creak.
    MMI V (Moderate shaking) ?
    People :
    Generally felt outside, and by almost everyone indoors. Most sleepers awakened. A few people alarmed.
    Fittings :
    Small unstable objects are displaced or upset. Some glassware and crockery may be broken. Hanging pictures knock against the wall. Open doors may swing. Cupboard doors secured by magnetic catches may open. Pendulum clocks stop, start, or change rate.
    Structures :
    Some large display windows cracked. A few earthenware toilet fixtures cracked.
    MMI VI (Strong shaking) ?
    People Felt by all. People and animals alarmed. Many run outside. Difficulty experienced in walking steadily.
    Fittings :
    Objects fall from shelves. Pictures fall from walls. Some furniture moved on smooth floors, some unsecured free-standing fireplaces moved. Glassware and crockery broken. Very unstable furniture overturned. Small church and school bells ring. Appliances move on bench or table tops. Filing cabinets or "easy glide" drawers may open (or shut).
    Structures :
    Slight damage to buildings with low standard. Some stucco or cement plaster falls. Large display windows broken. Damage to a few weak domestic chimneys, some may fall.
    Environment :
    Trees and bushes shake, or are heard to rustle. Loose material may be dislodged from sloping ground, e.g. existing slides, talus slopes, shingle slides.
    MMI VII (Very strong shaking) ?
    General alarm. Difficulty experienced in standing. Noticed by motorcar drivers who may stop.
    Fittings :
    Large bells ring. Furniture moves on smooth floors, may move on carpeted floors. Substantial damage to fragile contents of buildings.
    Structures :
    Unreinforced stone and brick walls cracked. Low standard buildings cracked with some minor masonry falls. A few instances of damage to buildings of ordinary workmanship. Unbraced parapets, unbraced brick gables, and architectural ornaments fall. Roofing tiles, especially ridge tiles may be dislodged. Many unreinforced domestic chimneys damaged, often falling from roof-line. Water tanks Type I burst. A few instances of damage to brick veneers and plaster or cement-based linings. Unrestrained water cylinders (hot-water cylinders) may move and leak. Some common windows cracked. Suspended ceilings damaged.
    Environment :
    Water made turbid by stirred up mud. Small slides such as falls of sand and gravel banks, and small rock-falls from steep slopes and cuttings. Instances of settlement of unconsolidated or wet, or weak soils. Some fine cracks appear in sloping ground. A few instances of liquefaction (i.e. small water and sand ejections).
    MMI VIII (Severe shaking) ?
    People Alarm may approach panic. Steering of motorcars greatly affected. Structures : Low standard buildings heavily damaged, some collapse. ordinary workmanship buildings damaged, some with partial collapse. Reinforced masonry or concrete buildings damaged in some cases. A few instances of damage to buildings and bridges designed and built to resist earthquakes. Monuments and pre-1976 elevated tanks and factory stacks twisted or brought down. Some pre-1965 infill masonry panels damaged. A few post-1980 brick veneers damaged. Decayed timber piles of houses damaged. Houses not secured to foundations may move. Most unreinforced domestic chimneys damaged, some below roof-line, many brought down. Environment : Cracks appear on steep slopes and in wet ground. Small to moderate slides in roadside cuttings and unsupported excavations. Small water and sand ejections and localized lateral spreading adjacent to streams, canals, lakes, etc.
    MMI IX (Violent shaking) ?
    Structures Many low standard buildings destroyed. Ordinary workmanship buildings heavily damaged, some collapse. Reinforced masonry or concrete buildings damaged, some with partial collapse. Buildings and bridges designed and built to resist earthquakes damaged in some cases, some with flexible frames seriously damaged. Damage or permanent distortion to some buildings and bridges, designed and built to normal use standards. Houses not secured to foundations shifted off. Brick veneers fall and expose frames. Environment : Cracking of ground conspicuous. Landsliding general on steep slopes. Liquefaction effects intensified and more widespread, with large lateral spreading and flow sliding adjacent to streams, canals, lakes, etc.
    Tell us your experience and how many seconds the shaking lasted + let us know if your property has been damaged (even slight damage). (max. 500 characters)
    * mandatory fields