Moderate mag. 3.9 earthquake - 2.3 mi southeast of San Leandro, Alameda County, California, USA, on 28 Jun 6:29 pm (GMT -7) -

Moderate mag. 3.9 earthquake - 2.3 mi southeast of San Leandro, Alameda County, California, USA, on 28 Jun 6:29 pm (GMT -7)

Moderate magnitude 3.9 earthquake at 9 km depth

29 Jun 01:30 UTC: First to report: VolcanoDiscovery after 52 seconds.
29 Jun 01:31: Now using data updates from USGS
... [show all] ...
29 Jun 05:50: Hypocenter depth recalculated from 10.6 to 9.2 km (from 6.6 to 5.7 mi).
Update Tue, 29 Jun 2021, 01:36
Moderate magnitude 4.1 earthquake 2 miles southeast of San Leandro, California, United States
4.1 quake 28 Jun 6:29 pm (GMT -7)
4.1 quake 28 Jun 6:29 pm (GMT -7)
A shallow magnitude 4.1 earthquake was reported early evening near San Leandro, Alameda County, California, USA.
According to the United States Geological Survey, the quake hit on Monday 28 June 2021 at 6:29 pm local time at a shallow depth of 6.6 miles. Shallow earthquakes are felt more strongly than deeper ones as they are closer to the surface. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.
Our monitoring service identified a second report from the European-Mediterranean Seismological Centre (EMSC) which listed the quake at magnitude 4.1 as well.
Based on the preliminary seismic data, the quake was probably felt by many people in the area of the epicenter. It should not have caused significant damage, other than objects falling from shelves, broken windows, etc.
In Ashland (pop. 21,900) located 1 miles from the epicenter, Castro Valley (pop. 61,400) 2 miles away, and San Leandro (pop. 90,700) 2 miles away, the quake should have been felt as light shaking.
Weak shaking might have been felt in Hayward (pop. 158,300) located 4 miles from the epicenter, Alameda (pop. 78,600) 9 miles away, San Ramon (pop. 76,100) 9 miles away, Oakland (pop. 419,300) 10 miles away, and San Francisco (pop. 864,800) 17 miles away.
Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include San Jose (pop. 1,026,900) located 29 miles from the epicenter.

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Earthquake data

Date & time: Jun 29, 2021 01:29:48 UTC -
Local time at epicenter: 28 Jun 6:29 pm (GMT -7)
Magnitude: 3.9
Depth: 9.2 km
Epicenter latitude / longitude: 37.70617°N / 122.12233°W (Alameda, California, United States)
Antipode: 37.706°S / 57.878°E
Nearest volcano: Clear Lake (151 km / 94 mi)
Nearby towns and cities:
1 km (1 mi) NNW of Ashland (pop: 21,900) --> See nearby quakes!
3 km (2 mi) WNW of Castro Valley (pop: 61,400) --> See nearby quakes!
4 km (2 mi) SE of San Leandro (pop: 90,700) --> See nearby quakes!
6 km (3 mi) NW of Hayward (pop: 158,300) --> See nearby quakes!
14 km (9 mi) ESE of Alameda (pop: 78,600) --> See nearby quakes!
15 km (9 mi) WSW of San Ramon (pop: 76,100) --> See nearby quakes!
17 km (11 mi) SE of Oakland (pop: 419,300) --> See nearby quakes!
27 km (17 mi) ESE of San Francisco (pop: 864,800) --> See nearby quakes!
45 km (28 mi) NNW of San Jose (pop: 1,026,900) --> See nearby quakes!
112 km (69 mi) SSW of Sacramento (pop: 490,700) --> See nearby quakes!
Weather at epicenter at time of quake:
Broken Clouds 19.8°C (68 F), humidity: 72%, wind: 3 m/s (5 kts) from WSW
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 4.5 x 1010 joules (12.4 megawatt hours, equivalent to 10.7 tons of TNT) | about seismic energy
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Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
Mag.DepthLocationSource
3.99.2 km3km N of San Lorenzo, CAUSGS
4.010 kmSAN FRANCISCO BAY AREA, CALIF.EMSC

User reports for this quake (2416)

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
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Oakland CA,94606 (15.2 km NW of epicenter) [Map] / Weak shaking (MMI III) / single vertical bump / 2-5 s
Alameda, California (12.5 km NW of epicenter) [Map] / Very weak shaking (MMI II)
Burlingame, San Mateo, California (25.2 km SW of epicenter) [Map] / Weak shaking (MMI III) / horizontal (sideways) swinging / very short
San Francisco (32.8 km W of epicenter) [Map] / Very weak shaking (MMI II) / 2-5 s : Walls shaking  
Oakland (23.4 km NNW of epicenter) [Map] / Weak shaking (MMI III) / horizontal (sideways) swinging / 2-5 s
Alameda Ca (6.8 km WNW of epicenter) [Map] / Weak shaking (MMI III) : very short shaking, approximately 5 sec long  
oakland, ca (16.3 km WNW of epicenter) [Map] / Weak shaking (MMI III) / horizontal (sideways) swinging
Pleasanton, Alameda, California (24.2 km E of epicenter) [Map] / Weak shaking (MMI III) / horizontal (sideways) swinging / 2-5 s
San Francisco, California, United States (25.7 km W of epicenter) [Map] / Very weak shaking (MMI II) / horizontal (sideways) swinging / 2-5 s
San Ramon, Contra Costa, California (16.8 km ENE of epicenter) [Map] / Weak shaking (MMI III)
Oakland (18.1 km NW of epicenter) [Map] / Weak shaking (MMI III) / simple rolling (tilting sideways along one direction) / 2-5 s
South San Francisco, San Mateo, California (27.9 km W of epicenter) [Map] / Very weak shaking (MMI II) / horizontal (sideways) swinging / very short
Oakland (12 km NW of epicenter) [Map] / Weak shaking (MMI III) / very short
Oakland (8.7 km NNW of epicenter) [Map] / Light shaking (MMI IV) / rattling, vibrating / 1-2 s
fremont (21.8 km SSE of epicenter) [Map] / Weak shaking (MMI III) / rattling, vibrating / 2-5 s
Walnut Creek, CA (22.2 km NNE of epicenter) [Map] / Weak shaking (MMI III) / single lateral shake / 2-5 s
san francisco (18.3 km SW of epicenter) [Map] / Weak shaking (MMI III)
Livermore, Alameda, California (29 km ESE of epicenter) [Map] / Very weak shaking (MMI II) / single lateral shake / 1-2 s
Fremont, Alameda, California (22 km SE of epicenter) [Map] / Weak shaking (MMI III) / single lateral shake / 1-2 s
San Ramon (14.2 km ENE of epicenter) [Map] / Very weak shaking (MMI II)
Burlingame, ca (25.3 km WSW of epicenter) [Map] / Light shaking (MMI IV)
Noe Valley, San Francisco County, California (26.1 km W of epicenter) [Map] / Very weak shaking (MMI II)
Petaluma / Very weak shaking (MMI II) / horizontal (sideways) swinging / 2-5 s : Was on phone with friends in Alameda - he kept saying‘earthquake’ and a few seconds later I felt some ver mild shaking here  
Bakersfield / Very weak shaking (MMI II) / horizontal (sideways) swinging / 2-5 s
San Francisco, ca in an Apartment bldg. it was a g / Light shaking (MMI IV) / horizontal (sideways) swinging / 10-15 s : It was a mild side ways shaking lasting 10-15 seconds.  
San Mateo / Light shaking (MMI IV) / single lateral shake / 1-2 s : Lateral motion  
CRESCO RESTAURANT SUPPLY, 2018 S. VAN NESS AVE, FR / Weak shaking (MMI III) / vibration and rolling / 15-20 s
Modesto, California / Very weak shaking (MMI II) / rattling, vibrating / 2-5 s : I was upstairs. My office chair moved and my dresser moved and rattled.  
Sacramento / Weak shaking (MMI III) / horizontal (sideways) swinging
Visalia, ca / Moderate shaking (MMI V) / complex rolling (tilting in multiple directions) / 2-5 s
Bakersfield / Very weak shaking (MMI II) / horizontal (sideways) swinging / 2-5 s
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