Earthquake Thread ~ Always Updated

Or it did and the hill was so much higher, lol. Sorry - couldn't resist

Lol! Ok, there are always other perspectives! I bow down!

:this1:

Magnitude 3.7
Region TARAPACA, CHILE
Date time 2017-02-14 03:14:10.0 UTC
Location 21.26 S ; 69.01 W
Depth 94 km

[link to m.emsc.eu]

Magnitude 2.6
Region SICILY, ITALY
Date time 2017-02-14 03:43:27.4 UTC
Location 38.34 N ; 14.87 E
Depth 137 km

[link to m.emsc.eu]

Magnitude 3.0
Region EASTERN TURKEY
Date time 2017-02-14 03:50:30.2 UTC
Location 39.90 N ; 41.93 E
Depth 9 km

[link to m.emsc.eu]

On top of that, Mount Shasta has 56 feet of snow, my cousin in Truckee has 15 feet of snow at her home! That is a lot of water!

I would imagine that wouldn't help the situation...

Nice find, thanks!

Alaska (AK) Recent Quakes:
[link to earthquake.alaska.edu]

:bump4:

pop up

Magnitude 4.4
Region CELEBES SEA
Date time 2017-02-14 00:47:12.0 UTC
Location 2.25 N ; 124.94 E
Depth 218 km
[link to m.emsc.eu]

Recent Earthquakes Near Oroville, California, United States
[link to earthquaketrack.com]

On 1 August 1975, an earthquake of magnitude (M) 5.7 occurred 12 km south of Lake Oroville (Figure 1). The earthquake was accompanied by surface faulting which extended for several kilometers (Akers and McQuilkin, 1975). The earthquake sequence (M > 3) consisted of five foreshocks, a main shock, and numerous aftershocks. The sequence included seven earthquakes of magnitude greater than 4.6 (Morrison and others, 1976). Faulting occurred on a northwest trending zone of the Foothills fault system (Hart and Rapp, 1975). The aftershocks defined a zone extending 16 km south from the dam and dipping 60 degrees west (Lester and others, 1975). Focal mechanisms indicated normal faulting with the Great Valley side down relative to the Sierra Nevada; leveling surveys confirmed this sense of motion.

Two factors suggest that Lake Oroville (maximum depth 220 m; storage capacity 413 billion m3) contributed to both the location and timing of the 1975 earthquake. The first factor is the proximity of the earthquake to the lake, and the extension of the causative fault to the lake as indicated by geologic, seismologic, and geodetic data (Department of Water Resources, 1979). This provides a possible avenue for water under pressure as high as 20 bars, resulting from a water depth of more than 200 meters into the fault zone (Lahr and others, 1976). The second factor is the occurrence of the earthquake following an unprecedented seasonal fluctuation in lake levels. This factor is illustrated in figure 2a, which shows lake levels (in meters above sea level) and number of earthquakes per month within 40 km of Oroville from 1964 to 1976. During the winter of 1974-1975, the lake was drawn down to its lowest level since filling to repair the intakes to the power plant. This unprecedented drawdown and subsequent refilling was followed by the earthquake sequence of 1975.

Failure occurs because the rapid drawdown immediately reduces the normal stress, whereas the reduction in pore pressure diffuses more slowly in the underlying rocks. The result is excess pore pressure in the underlying rocks which diminishes the effective stress or strength. This is borne out in figure 3 which shows that seismicity is greatly diminished during episodes of reservoir filling, and that the largest earthquakes are associated with the most rapid drawdowns in lake levels.

In this regard, Simpson (1976, p. 146) noted the paradox "that if there is an indication of an impending increase in the level of seismicity, one of the obvious ways of decreasing danger downstream from the dam---the rapid emptying of the reservoir---may in fact increase the danger by triggering a further increase in the level of activity." This scenario is reflected in figure 3, which shows that the most rapid drawdowns in lake levels are accompanied by the greatest seismic activity. The occurrence of the two M > 2.5 earthquakes in 1980 following the two peaks of rapid filling and rapid drawdown resulting from severe storms suggests an extreme sensitivity of the fault zone to sharp fluctuations in lake level.

SOME KEY POINTS:
*The 1975 Oroville earthquake of M 5.7 occurred almost eight years after the creation of Lake Oroville. This earthquake immediately followed the largest seasonal fluctuation in the lake level to that date.
*Seismic monitoring at Oroville since 1975 shows that the local seismicity decreases as the lake fills during winter and spring, and that the strongest earthquakes occur as the lake empties during summer and fall. This pattern has been remarkably consistent during the past seven years, and indicates that the seasonal fluctuations in water depth at Lake Oroville control the earthquake occurrences.
[link to www.johnmartin.com]

:sw_unbelievable:
Ummmmm...this doesn't seem good at all!

Re: Dam eq flood in '75


Causation is very difficult to prove....


Perhaps its all just like random walk hypothesis

Oroville Dam earthquake investigation may be needed
*Article From NOVEMBER 29, 2013*

A recent federal inspection has concluded that Oroville Dam, the tallest dam in the nation, needs a comprehensive earthquake safety assessment.
The dam on the Feather River is the primary storage facility for the State Water Project, the state-owned plumbing system that provides drinking water to more than 23 million people across California. Failure of the dam could inundate not only the city of Oroville but numerous other communities downstream, including Yuba City, Marysville and even West Sacramento.

Inspectors recommended the earthquake safety assessment based on newer information about earthquake hazards in the vicinity of the dam. Officials at the California Department of Water Resources, which manages the dam, say they don’t plan to conduct the recommended review because they don’t think the expense is justified. State water officials say the dam is sufficiently strong. “Even with today’s understanding of seismicity and ground motions, Oroville still would meet the criteria that would be set today,” said David Panec, chief of dam safety at the DWR’s operations and maintenance division. “The dam is essentially overbuilt.”

:sw_hmmm:

Not everyone is confident. Ronald Stork, a senior policy advocate at Friends of the River, said the call for further study of Oroville Dam should not be taken lightly. In recent years, after modern studies, numerous other earthen dams in California have been shown to be vulnerable to earthquakes. Stork noted Oroville is also considered a “classic case” for something known as reservoir-induced seismicity. In this phenomenon, the reservoir itself can cause earthquakes, because the enormous weight of water stored behind the dam is enough to shift the Earth’s crust. Studies have documented the phenomenon at Oroville. “A dam with a whole lot of shaking going on … does seem to be something you need to be really careful about,” said Stork, who monitors dam regulation across the state. “You lose a 3.5million acre-foot reservoir – the tallest in the United States – and that could cause a whole mess of downstream trouble.”

:sw_wow:
Enough Said....next up the potential for possible earthquake due to the enormous weight of water stored behind dam is enough to shift the Earth's crust.

Full Article In The Link:
[link to www.sacbee.com]

:getting away:
Happy Valentines to the Moontards
.c.c

to you too CC

WA :Relax 1:
Happy Valentines .c.c

Since many are here now with S!

Last Edited by Isis One on 02/14/2017 01:33 AM

Hey hey.

OROVILLE EARTHQUAKES:

Magnitude: 2.2 Quarry Blast
Region: 10km N of Oroville, California
Date/Time: 2016-01-13 21:13:59 UTC
Location: 39.605°N 121.578°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 1.9 Quarry Blast
Region: 10km N of Oroville, California
Date/Time: 2016-02-11 19:45:29 UTC
Location: 39.608°N 121.568°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 2.0 Quarry Blast
Region: 10km N of Oroville, California
Date/Time: 2016-02-23 19:45:02 UTC
Location: 39.610°N 121.566°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 2.6 Quarry Blast
Region: 11km N of Oroville, California
Dare/Time: 2016-03-15 19:55:53 UTC
Location: 39.614°N 121.565°W
Depth: -0.2 km
[link to earthquake.usgs.gov]
[link to www.friendlyforecast.com]

Magnitude: 2.0 Quarry Blast
Region: 11km N of Oroville, California
Date/Time:;2016-04-12 19:05:34 UTC
Location: 39.617°N 121.565°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 1.9 Quarry Blast
Region: 10km N of Oroville, California
Date/Time:2016-05-26 18:29:25 UTC
Location: 39.606°N 121.577°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 1.9 Quarry Blast
Region: 11km N of Oroville, California
Date/Time: 2016-06-21 18:32:30 UTC
Location: 39.613°N 121.565°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

Magnitude: 1.9 Quarry Blast
Region: 11km N of Oroville, California
Date/Time: 2016-11-09 21:24:07 UTC
Location: 39.614°N 121.561°W
Depth: -0.3 km
[link to earthquake.usgs.gov]

Magnitude: 1.9 Quarry Blast
Region: 6km N of Oroville, California
Date/Time: 2016-12-09 21:06:50 UTC
Location: 39.572°N 121.550°W
Depth: -0.3 km
[link to earthquake.usgs.gov]

Magnitude: 2.1 Quarry Blast
Region: 7km N of Oroville, California
Date/Time: 2017-02-08 19:56:42 UTC
Location: 39.581°N 121.551°W
Depth: -0.2 km
[link to earthquake.usgs.gov]

*Very interesting and kind of disturbing.
Each blast seems like clockwork.
Compare the magnitudes, dates and timestamps to each month.
Every month for a year, except for January 2017- nothing in Oroville.
I also couldn't find anything close to or before 2016.

:bump4:

Happy Valentine's Day Captain!!!
:sw_specialmoon:
Moon Love

Awe...I love your Valentine's Day Card!!!

:sw_xo-clouds:
Happy Valentine's Day Isis

:sw_wink:

Hey you. Always spot on with updates. Thank you.

Thanks SW! I made it a few years ago. Happy Valentine's Day to you too!!

Last Edited by Isis One on 02/14/2017 02:35 AM

Magnitude 3.3
Region NEAR THE COAST OF WESTERN TURKEY
Date time 2017-02-14 04:39:14.4 UTC
Location 39.55 N ; 26.14 E
Depth 2 km
Macroseismic
Intensity F Effects: Felt

[link to m.emsc.eu]

Magnitude 3.0
Region NEVADA
Date time 2017-02-14 04:40:29.1 UTC
Location 41.50 N ; 116.12 W
Depth 8 km

[link to m.emsc.eu]