M1.6 Earthquake near Rancho Tehama Reserve, CA — 09 August 2026
A micro earthquake of magnitude 1.6 was recorded near Rancho Tehama Reserve, CA on , with an epicentre 41 km west-northwest of Rancho Tehama Reserve, at a focal depth of -0.6 km.
Time (UTC): 2026-08-09 21:45:06
Time (your timezone): —
Magnitude: 1.6 (micro)
Focal depth: -0.6 km (shallow)
Epicentre: 40.1755, -122.8320
Location: 41 km WNW of Rancho Tehama Reserve, CA
USGS link to NOAA tsunami information: Not linked
Review status: Automatic
Source: USGS event page
How strong was this earthquake?
Micro earthquakes are almost never felt at the surface and are recorded only by seismographs.
A magnitude 1.6 earthquake radiates roughly 3.8 kg of TNT equivalent in seismic energy.
The USGS assigns this earthquake a significance score of 39, which is below the USGS threshold of more than 600 for its significant-earthquake list. The ranking combines magnitude with available Did You Feel It responses and PAGER alert level; it is not a direct measurement of damage.
Where was the epicentre?
The epicentre was located at 40.1755, -122.8320 — 41 km west-northwest of Rancho Tehama Reserve. The closest other recorded event was a magnitude 3.4 earthquake 55 km west-southwest of here on 08 August 2026.
Why the -1 km depth matters
At -1 km this was a shallow earthquake. Shallow events release their energy close to the surface, so for a given magnitude they produce noticeably stronger shaking — and more damage — than deeper ones. Roughly three quarters of all earthquakes worldwide occur at shallow depths.
This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, events this small are usually detected by instruments rather than people. Its shallow focus makes stronger surface shaking more likely than for a deeper event of the same magnitude.
What does the tsunami information flag mean?
The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M1.6 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.
How earthquakes generate tsunamis, and what the alert levels mean →
Aftershocks and local seismic history
No further earthquakes have been recorded within about 150 km of the epicentre since this event was recorded.
16 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 5.6 event near Redwood Valley on 24 June 2026. This M1.6 event released about 966,051 times less energy than that event.
How long aftershock sequences last, and how large they get →
Where this event sits in the record
This earthquake is part of the August 2026 worldwide record. Browse the full monthly archive to compare periods.
Nearest recorded earthquakes to this epicentre
- M3.4 earthquake near Covelo, CA — (55 km WSW)
- M1.7 earthquake near Willits, CA — (96 km SSW)
- M1.5 earthquake near Cobb, CA — (145 km S)
- M0.7 earthquake near Cloverdale, CA — (148 km S)
- M0.3 earthquake near Cobb, CA — (148 km S)
- M1.8 earthquake near Cobb, CA — (148 km S)
- M0.3 earthquake near Cobb, CA — (149 km S)
- M1.2 earthquake near Cobb, CA — (149 km S)
- M1.6 earthquake near Cobb, CA — (149 km S)
- M1.0 earthquake near Cobb, CA — (150 km S)
Other magnitude 1 earthquakes worldwide
- M1.4 earthquake near Valdez, Alaska —
- M1.6 earthquake near Blyn, Washington —
- M1.8 earthquake near Balmorhea, Texas —
- M1.6 earthquake near Lompoc, CA —
- M1.4 earthquake near Lompoc, CA —
- M1.5 earthquake near Mammoth Lakes, CA —
- M1.5 earthquake near San Martin, CA —
- M1.5 earthquake near Karluk, Alaska —
Questions about this earthquake
How strong is a magnitude 1.6 earthquake?
Micro earthquakes are almost never felt at the surface and are recorded only by seismographs. A magnitude 1.6 earthquake radiates roughly 3.8 kg of TNT equivalent in seismic energy.
How deep was the earthquake near Rancho Tehama Reserve?
At -1 km this was a shallow earthquake. Shallow events release their energy close to the surface, so for a given magnitude they produce noticeably stronger shaking — and more damage — than deeper ones. Roughly three quarters of all earthquakes worldwide occur at shallow depths.
Was the M1.6 earthquake near Rancho Tehama Reserve felt?
This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, events this small are usually detected by instruments rather than people. Its shallow focus makes stronger surface shaking more likely than for a deeper event of the same magnitude.
What does the USGS tsunami field mean for this event?
The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M1.6 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.
Have there been aftershocks?
No further earthquakes have been recorded within about 150 km of the epicentre since this event was recorded.
How often do earthquakes happen near Rancho Tehama Reserve?
16 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 5.6 event near Redwood Valley on 24 June 2026. This M1.6 event released about 966,051 times less energy than that event.