Saturday, October 31, 2015

[Geology2] Babe Ruth and earthquake hazard maps



Babe Ruth and earthquake hazard maps

Date:
October 29, 2015
Source:
Geological Society of America
Summary:
Researchers have turned to an unusual source -- Major League Baseball -- to help learn why maps used to predict shaking in future earthquakes often do poorly.

Northwestern University researchers have turned to an unusual source -- Major League Baseball -- to help learn why maps used to predict shaking in future earthquakes often do poorly.

Earthquake hazard maps use assumptions about where, when, and how big future earthquakes will be to predict the level of shaking. The results are used in designing earthquake-resistant buildings. However, as the study's lead author, earth science and statistics graduate student Edward Brooks, explains "sometimes the maps do well, and sometimes they do poorly. In particular, the shaking and thus damage in some recent large earthquakes was much larger than expected."

Part of the problem is that seismologists have not developed ways to describe how well these maps perform. As Seth Stein, William Deering Professor of Geological Sciences explains "we need the kind of information the weather service has, where they can tell you how much confidence to have in their forecasts."

The question is how to measure performance. Bruce Spencer, professor of statistics, explains that "it's like asking how good a baseball player Babe Ruth was. The answer depends on how one measures performance. In many seasons Ruth led the league in both home runs and in the number of times he struck out. By one measure he did very well, and by another, very poorly. In the same way, we are using several measures to describe how hazard maps perform."

Another problem is that the hazard maps try to forecast shaking over hundreds over years, because buildings have long lifetimes. As a result, it takes a long time to tell how well a map is working. To get around this, the team looked backwards in time, using records of earthquake shaking in Japan that go back 500 years. They compared the shaking to the forecasts of the published hazard maps. They also compared the shaking to maps in which the expected shaking was the same everywhere in Japan, and maps in which the expected shaking at places was assigned at random from the published maps.

The results were surprising. In Brook's words "it turns out that by the most commonly used measure using the uniform and randomized maps work better than the published maps. By another measure, the published maps work better."

The message, in Stein's view, is that seismologists need to know a lot more about how these maps work. "Some of the problem is likely to be that how earthquakes occur in space and time is more complicated that the maps assume. Until we get a better handle on this, people using earthquake hazard maps should recognize that they have large uncertainties. Brightly colored maps look good, but the earth doesn't have to obey them and sometimes won't."

This research will be presented at the 2015 Annual Meeting of the Geological Society of America in Baltimore, MD, as part of the Bridging Two Continents joint "meeting-within-a meeting" with the Geological Society of China.


Story Source:

The above post is reprinted from materials provided by Geological Society of America. Note: Materials may be edited for content and length.



Geological Society of America. "Babe Ruth and earthquake hazard maps." ScienceDaily. ScienceDaily, 29 October 2015. <www.sciencedaily.com/releases/2015/10/151029190842.htm>.

--


__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___

[Geology2] Large igneous provinces linked to extinction events



Large igneous provinces linked to extinction events

Date:
October 30, 2015
Source:
Geological Society of America
Summary:
Mass extinction events are sometimes portrayed in illustrations of volcanic eruptions causing widespread destruction. According to experts this interpretation may have some truth behind it, but not in the instantaneous way we might think.

Mass extinction events are sometimes portrayed in illustrations of volcanic eruptions causing widespread destruction. According to Dr. Richard E. Ernst of Carleton University, Ottawa, Canada, expert on Large Igneous Provinces (LIPs), this interpretation may have some truth behind it, but not in the instantaneous way we might think. Ernst will report on his research on 1 November at the Geological Society of America's Annual Meeting in Baltimore, Maryland, USA.

The basaltic lava flowing from ancient volcanoes and the portion of magma (liquid rock) emplaced underground can create geologic conditions linked with climate change and, subsequently, extinction events. This climatic effect is particularly true for LIPs, in which mainly basaltic magma up to millions of cubic kilometers can be emplaced in a geologically short time of less than a few million years.

"The most dramatic climatic effect is global warming due to greenhouse-gases from LIPs," explains Ernst. "Subsequent cooling (and even global glaciations) can be caused by CO2 drawdown by weathering of LIP-related basalts."

There are currently numerous LIPs correlated with the timing of extinction events over the last few hundred million years, so there is a clear link to be explored by researchers like Ernst and his colleagues. He notes that the research literature on the links between LIPs and catastrophic climatic change is rapidly expanding.

How do researchers know this occurred? Improved isotope dating is confirming the long-proposed extinction-LIP link. Additionally, the environmental/climatic changes can be recorded in sedimentary isotopic compositions that record the structure of seawater in ancient times.

There are additional environmental effects associated with LIP deposition, Ernst reports. "Effects associated with LIPs also include oceanic anoxia (massive marine organism die off due to oxygen deficiency), sea level changes, etc." The sheer size of an LIP is not the only factor. "Also contributing to climatic/extinction effects are the abundance of LIP-produced pyroclastic material and volatile fluxes that reach the stratosphere, and in particular the role of super-eruptions."

Climate feedbacks are also an important factor. Warming caused by LIPs could cause the destabilization of frozen methane clathrates, which then releases more greenhouse gases and causes more warming. Ernst notes that paleogeography and location of the LIPs may have affected the climate as well. "An important global terrane effect is the surface extent of basalts at the time, and the portion which is at low latitudes --factors which increase the efficiency of the CO2 drawdown (and global cooling) through weathering."


Story Source:

The above post is reprinted from materials provided by Geological Society of America. Note: Materials may be edited for content and length.



Geological Society of America. "Large igneous provinces linked to extinction events." ScienceDaily. ScienceDaily, 30 October 2015. <www.sciencedaily.com/releases/2015/10/151030124531.htm>.

--


__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___

[Geology2] Mass gains of Antarctic Ice Sheet greater than losses



Mass gains of Antarctic Ice Sheet greater than losses

Date:
October 30, 2015
Source:
NASA/Goddard Space Flight Center
Summary:
A new study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.

This map shows the rates of mass changes from ICESat 2003-2008 over Antarctica. Sums are for all of Antarctica: East Antarctica (EA, 2-17); interior West Antarctica (WA2, 1, 18, 19, and 23); coastal West Antarctica (WA1, 20-21); and the Antarctic Peninsula (24-27). A gigaton (Gt) corresponds to a billion metric tons, or 1.1 billion U.S. tons.
Credit: Jay Zwally/ Journal of Glaciology

A new NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.

The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change's (IPCC) 2013 report, which says that Antarctica is overall losing land ice.

According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008.

"We're essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica," said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study, which was published on Oct. 30 in the Journal of Glaciology. "Our main disagreement is for East Antarctica and the interior of West Antarctica -- there, we see an ice gain that exceeds the losses in the other areas." Zwally added that his team "measured small height changes over large areas, as well as the large changes observed over smaller areas."

Scientists calculate how much the ice sheet is growing or shrinking from the changes in surface height that are measured by the satellite altimeters. In locations where the amount of new snowfall accumulating on an ice sheet is not equal to the ice flow downward and outward to the ocean, the surface height changes and the ice-sheet mass grows or shrinks.

But it might only take a few decades for Antarctica's growth to reverse, according to Zwally. "If the losses of the Antarctic Peninsula and parts of West Antarctica continue to increase at the same rate they've been increasing for the last two decades, the losses will catch up with the long-term gain in East Antarctica in 20 or 30 years -- I don't think there will be enough snowfall increase to offset these losses."

The study analyzed changes in the surface height of the Antarctic ice sheet measured by radar altimeters on two European Space Agency European Remote Sensing (ERS) satellites, spanning from 1992 to 2001, and by the laser altimeter on NASA's Ice, Cloud, and land Elevation Satellite (ICESat) from 2003 to 2008.

Zwally said that while other scientists have assumed that the gains in elevation seen in East Antarctica are due to recent increases in snow accumulation, his team used meteorological data beginning in 1979 to show that the snowfall in East Antarctica actually decreased by 11 billion tons per year during both the ERS and ICESat periods. They also used information on snow accumulation for tens of thousands of years, derived by other scientists from ice cores, to conclude that East Antarctica has been thickening for a very long time.

"At the end of the last Ice Age, the air became warmer and carried more moisture across the continent, doubling the amount of snow dropped on the ice sheet," Zwally said.

The extra snowfall that began 10,000 years ago has been slowly accumulating on the ice sheet and compacting into solid ice over millennia, thickening the ice in East Antarctica and the interior of West Antarctica by an average of 0.7 inches (1.7 centimeters) per year. This small thickening, sustained over thousands of years and spread over the vast expanse of these sectors of Antarctica, corresponds to a very large gain of ice -- enough to outweigh the losses from fast-flowing glaciers in other parts of the continent and reduce global sea level rise.

Zwally's team calculated that the mass gain from the thickening of East Antarctica remained steady from 1992 to 2008 at 200 billion tons per year, while the ice losses from the coastal regions of West Antarctica and the Antarctic Peninsula increased by 65 billion tons per year.

"The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away," Zwally said. "But this is also bad news. If the 0.27 millimeters per year of sea level rise attributed to Antarctica in the IPCC report is not really coming from Antarctica, there must be some other contribution to sea level rise that is not accounted for."

"The new study highlights the difficulties of measuring the small changes in ice height happening in East Antarctica," said Ben Smith, a glaciologist with the University of Washington in Seattle who was not involved in Zwally's study.

"Doing altimetry accurately for very large areas is extraordinarily difficult, and there are measurements of snow accumulation that need to be done independently to understand what's happening in these places," Smith said.

To help accurately measure changes in Antarctica, NASA is developing the successor to the ICESat mission, ICESat-2, which is scheduled to launch in 2018. "ICESat-2 will measure changes in the ice sheet within the thickness of a No. 2 pencil," said Tom Neumann, a glaciologist at Goddard and deputy project scientist for ICESat-2. "It will contribute to solving the problem of Antarctica's mass balance by providing a long-term record of elevation changes."


Story Source:

The above post is reprinted from materials provided by NASA/Goddard Space Flight Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Zwally, H. Jay, ; Li, Jun; Robbins, John W.; Saba, Jack L.; Yi, Donghui; Brenner, Anita C. Mass gains of the Antarctic ice sheet exceed losses. Journal of Glaciology, 2015 DOI: 10.3189/2015JoG15J071


NASA/Goddard Space Flight Center. "Mass gains of Antarctic Ice Sheet greater than losses." ScienceDaily. ScienceDaily, 30 October 2015. <www.sciencedaily.com/releases/2015/10/151030220523.htm>.

--


__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___

[Geology2] Hunters Discover Massive “Gash” in Earth 150 Miles from Yellowstone Caldera





__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___

Friday, October 30, 2015

[californiadisasters] Gibraltar Incident - Los Padres NF - Santa Barbara Co.



This from Airtankers group on Yahoo: 

A small but dangerous wind driven wildfire was worked by at least 11 airtankers on Thursday (10-29).                                                                                                

The "Gibraltar Fire" broke out in the early morning hours (05:15) East of El Camino Road and East of Gibraltar Road between Montecito Peak and Cold Springs Saddle, within the Los Padres National Forest (Northeast of Santa Barbara) this area is steep and rugged so the potential for the fire to spread rapidly with the strong winds was always a danger.                                              

Evacuations were in effect North of Highway 192, East of Cold Springs Road, West of Buena Vista Drive, and East of Camino Cielo Road. No structures were reported destroyed in the fire, smoke from the fire forced the closures of some schools in the areas.  

Fire was only between 50-70 acres and was reported 50% contained today (10-30). The air tanker show included the following Tankers reported:

P2V's #14,#43. 

BAE-146's #12,#40. 

RJ-85's #160,#164. 

MD-87's #101,#105.  

S2's  #73,#78,#100. 

DC-10 #912.  

Tankers were reportedly reloading out of Santa Maria for this fire.                                                                  




__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

[californiadisasters] You probably won't survive zombie apocalypse in Los Angeles



You probably won't survive zombie apocalypse in Los Angeles, CareerBuilder says


By ABC7.com staff
Updated 1 hr 13 mins ago

LOS ANGELES (KABC) --
Los Angeles, Riverside and San Bernardino are not the place to be if there's a zombie apocalypse, according to CareerBuilder.

In the spirit of Halloween, CareerBuilder recently asked what many of us have: "What would happen if there was a zombie apocalypse?"

In answer to this question, CareerBuilder and Economic Modeling Specialists Intl. have released a totally necessary and 100 percent practical survey of the 10 U.S. cities most equipped - and the 10 cities least equipped - to survive an actual night of the living dead.

Los Angeles, Riverside and San Bernardino made the list.

The index is scored on eight different factors in four categories: ability to defend against the zombie-bite virus, ability to contain the virus, ability to find a cure and ability to outlast the epidemic with an ample food supply. The study is based on data from EMSI, which analyzes labor market data.

The 10 Metros Most Likely to Survive a Zombie Apocalypse
Perhaps a history fighting for freedom gave it the edge, but thanks to the right skills, population density and industry resources, Boston has the highest chance of surviving a zombie apocalypse, according to CareerBuilder's findings. Salt Lake City, Columbus, Baltimore and Virginia Beach are also well-positioned to win World War Z.

The 10 Metros Least Likely to Survive a Zombie Apocalypse
Although it may have survived an alien invasion in the movie Independence Day, New York City was found to be least equipped to survive an undead infiltration, ranking at the bottom of the list. Things aren't looking so good for Tampa, Los Angeles, Riverside, San Bernardino and Chicago, either.

Los Angeles ranked as the second-worst city for its ability to contain the virus.

Riverside and San Bernardino ranked as the fourth-worst equipped to defend themselves against a zombie ambush and second-least likely to find a cure for the common zombie infection.

Source: http://abc7.com/society/you-probably-wont-survive-zombie-apocalypse-in-los-angeles-careerbuilder-says/1059707/


__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

[californiadisasters] Valley Fire Dash Cam Video





__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

[californiadisasters] Graphic of the Day - California Fire Season 2015



Eclectic Arcania notes that all this burning is just the front end of a two-part disaster cycle in California of fire & water:

http://eclecticarcania.blogspot.com/2015/10/graphic-of-day-california-fire-season.html


__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

[californiadisasters] Graphic of the Day - El NiƱo Rainfall Probabilities



Eclectic Arcania hopes it does not wait until February like it did in 1997-1998:

http://eclecticarcania.blogspot.com/2015/10/graphic-of-day-el-nino-rainfall.html


__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

[californiadisasters] When Overkill Is Good



Eclectic Arcania never previously saw so much retardant adjacent to so small a fire:

http://eclecticarcania.blogspot.com/2015/10/picture-of-day-when-overkill-is-good.html


__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>


Be sure to check out our Links Section at http://groups.yahoo.com/group/californiadisasters/links
Please join our Discussion Group at http://groups.yahoo.com/group/californiadisasters_discussion/ for topical but extended discussions started here or for less topical but nonetheless relevant messages.





__,_._,___

Re: [Geology2] ‘Something Big Moving Out There=?UTF-8?Q?=E2=80=99?=



OH SHIT! ROFLMFAO!!!!!!

Lin

On Fri, Oct 30, 2015 at 1:47 PM, Kim Noyes kimnoyes@gmail.com [geology2] <geology2@yahoogroups.com> wrote:
 
[Attachment(s) from Kim Noyes included below]

They keep telling themselves it was a bear or a goat to comfort themselves during their brief visits out there..... but somebody did find one of these nearby:



On Fri, Oct 30, 2015 at 5:23 AM, Lin Kerns linkerns@gmail.com [geology2] <geology2@yahoogroups.com> wrote:
 

Seismic Station in Alaska Records a Disturbance That Wasn't an Earthquake: 'Something Big Moving Out There'

Oct. 29, 2015  Liz Klimas

Recordings taken at a station that detects seismic activity at Kultieth River Mountain in southeast Alaska would suggest that the area experienced a strong disturbance earlier this month.

But it was no earthquake.

The incident recorded by the Alaska Earthquake Center's seismic sensor, according to KTUU-TV, was actually the work of a bear, or at least that's what scientists think.

"We aren't sure for certain it was a bear, but the data shows indicates it was something big moving out there before the data stopped coming in," field engineer Scott Dalton told the news station.

The shaking detected by the station lasted for eight minutes and then transmission stopped.

"We still have power out there so we think that means that an animal dug up the cables between the sensor and the fiberglass hut that provides power," Dalton told KTUU.


Evidence of chewing was discovered on the lids of containers that hold the seismic sensors.

"Ever wonder what it looks like when a bear takes out a seismic station?" the center tweeted this week.


It appears that this station has been the target of other animal attacks the past as well.

"This same station was damaged last year by what we think was a goat," Dalton told the news station.

KTUU reported the station will not undergo repair until next year.

http://www.theblaze.com/stories/2015/10/29/seismic-station-in-alaska-records-a-disturbance-that-wasnt-an-earthquake-something-big-moving-out-there/
--




--




--


__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___

Re: [Geology2] ‘Something Big Moving Out There’ [1 Attachment]

[Attachment(s) from Kim Noyes included below]

They keep telling themselves it was a bear or a goat to comfort themselves during their brief visits out there..... but somebody did find one of these nearby:



On Fri, Oct 30, 2015 at 5:23 AM, Lin Kerns linkerns@gmail.com [geology2] <geology2@yahoogroups.com> wrote:
 

Seismic Station in Alaska Records a Disturbance That Wasn't an Earthquake: 'Something Big Moving Out There'

Oct. 29, 2015  Liz Klimas

Recordings taken at a station that detects seismic activity at Kultieth River Mountain in southeast Alaska would suggest that the area experienced a strong disturbance earlier this month.

But it was no earthquake.

The incident recorded by the Alaska Earthquake Center's seismic sensor, according to KTUU-TV, was actually the work of a bear, or at least that's what scientists think.

"We aren't sure for certain it was a bear, but the data shows indicates it was something big moving out there before the data stopped coming in," field engineer Scott Dalton told the news station.

The shaking detected by the station lasted for eight minutes and then transmission stopped.

"We still have power out there so we think that means that an animal dug up the cables between the sensor and the fiberglass hut that provides power," Dalton told KTUU.


Evidence of chewing was discovered on the lids of containers that hold the seismic sensors.

"Ever wonder what it looks like when a bear takes out a seismic station?" the center tweeted this week.


It appears that this station has been the target of other animal attacks the past as well.

"This same station was damaged last year by what we think was a goat," Dalton told the news station.

KTUU reported the station will not undergo repair until next year.

http://www.theblaze.com/stories/2015/10/29/seismic-station-in-alaska-records-a-disturbance-that-wasnt-an-earthquake-something-big-moving-out-there/
--




--


__._,_.___

Attachment(s) from Kim Noyes | View attachments on the web

1 of 1 Photo(s)


Posted by: Kim Noyes <kimnoyes@gmail.com>



__,_._,___

Re: [Geology2] Official behind earthquake advice to stand trial in Italy



Fucking idiots!

On Fri, Oct 30, 2015 at 5:14 AM, Lin Kerns linkerns@gmail.com [geology2] <geology2@yahoogroups.com> wrote:
 


In ruins: The 2009 L'Aquila earthquake killed over 300 people.

Joanna Faure Walker/Flickr (CC BY 2.0)

In ruins: The 2009 L'Aquila earthquake killed over 300 people.

Official behind earthquake advice to stand trial in Italy

By Edwin Cartlidge
29 October 2015

<SNIP>



--


__._,_.___

Posted by: Kim Noyes <kimnoyes@gmail.com>



__,_._,___

[Geology2] 3D Images of Magma Below Mono Craters Area



3D Images of Magma Below Mono Craters Area
Released: 10/29/2015




USGS scientist, Jared Peacock making sure the equipment is set up properly with good data coming in, and programming the data logger to collect magnetotelluric data for 24 hours as NAGT intern, Monica Mustain looks on.
USGS scientist, Jared Peacock making sure the equipment is set up properly with good data coming in, and programming the data logger to collect magnetotelluric data for 24 hours as NAGT intern, Monica Mustain looks on. (High resolution image)

A new conceptual model of the magma system below Mono Lake and Mono Craters in eastern California gives scientists a more detailed understanding of volcanic processes at depth, and a better model for forecasting volcanic unrest.

The Mono Craters volcanic area is ranked among the nation's high threat volcanoes. Recent eruptions at Mono Craters occurred about 600 years ago at Panum Crater, and about 350 years ago on Paoha Island in the middle of Mono Lake. The accuracy and high resolution of the new three-dimensional images of the magma chambers and volcanic "plumbing" below Mono Basin give scientists a better understanding of their size, shape and where the next eruption might occur.

To create the new 3D images, U.S. Geological Survey post-doctoral researcher Jared Peacock used a technology called magnetotellurics. The technology measures slight electrical currents naturally created by the movement of ions in the Earth's magnetic field (like the Aurora Borealis, or Northern Lights). The flow of these electrical currents through rock varies based on its composition and other properties. Old, dense rocks at depth are more resistant to electricity flowing through them, whereas fractured rocks containing fluids such as ground water, or hydrothermal fluids related to volcanic activity are less resistant. Magma chambers with liquid, melted rock, or a partially crystallized "mush," have a very low resistivity to current flow. 

The 3D resistivity images show at least two vertical magma columns 10 km (6 miles) deep. One column underneath Panum Crater, resembling the shape of a giraffe's neck, veers off horizontally, suggesting the presence of hydrothermal fluids near the surface. The other column, below South Coulee, gives no indication of recent near-surface activity. An older body of granitic rock, a pluton, was also discernable amid the columns of younger magma in the 3D imaging.

Using the electrical resistivity model and data from previous scientific studies of the area, Peacock was also able to shed light on a long-standing question of how the volcanic system may be related to nearby faults. Peacock observed a conductive anomaly west of Mono Craters that has been known as a site of long-period earthquakes. This correlation could be caused by either volcanic fluids from magma moving below the surface, or the release of fluids from nearby metamorphic rocks that are under high pressure and temperatures. More research needs to be done in that area to determine whether the cause of the long-period earthquakes is due to magmatic (volcanic) or metamorphic processes. A determination could give insight to the possibility of future volcanic activity in a new area. The resistivity imaging also indicated how other small faults on the east side of the Sierra Nevada may be connected at depth, and extend farther and deeper than previously known. 

"These new 3D images add detail to our existing knowledge of the volcanic system east of the Sierra Nevada, and enable us to make more accurate forecasts of volcanic unrest," said Margaret Mangan, Scientist-in-Charge of the USGS California Volcano Observatory.

Peacock's research paper, "Imaging the magmatic system of Mono Basin, California with magnetotellurics in three-dimensions," has been accepted for publication in the Journal of Geophysical Research – Solid Earth, is available online.

Threeā€“dimensional resistivity model (view looking northwest) showing anomalies below Mono Craters. The warm red and orange colors indicate material with low electrical resistively, and the cool blue colors indicate a high resistivity to an electrical current. Note the
Three–dimensional resistivity model (view looking northwest) showing anomalies below Mono Craters. The warm red and orange colors indicate material with low electrical resistively, and the cool blue colors indicate a high resistivity to an electrical current. Note the "giraffe's neck" -shaped anomaly below Panum Crater. Black dots are earthquake hypocenters. (High resolution image)


http://gallery.usgs.gov/images/10_23_2015/wBRe72Gtt5_10_23_2015/medium/MB_20131123_142.JPG

http://www.usgs.gov/newsroom/article.asp?ID=4374&from=rss&utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+usgs%2FnewsEverything+%28Newsroom+-+Everything%29#.VjOtgmuMX5F

--


__._,_.___

Posted by: Lin Kerns <linkerns@gmail.com>



__,_._,___
Newer Posts Older Posts Home