Monday, April 30, 2012

[Geology2] Yellowstone “Super-Eruption” less super, more frequent than thought



WSU GeoAnalytical Laboratory researchers offer new take on super-volcano

Yellowstone "Super-Eruption" less super, more frequent than thought

Monday, Apr. 30, 2012

Photo courtesy of Yellowstone Super Volcano Alert - History Channel Special
 
PULLMAN, Wash.— The Yellowstone "super-volcano" is a little less super—but more active—than previously thought.

Researchers at Washington State University and the Scottish Universities Environmental Research Centre say the biggest Yellowstone eruption, which created the 2 million year old Huckleberry Ridge deposit, was actually two different eruptions at least 6,000 years apart.
 
Their results paint a new picture of a more active volcano than previously thought and can help recalibrate the likelihood of another big eruption in the future. Before the researchers split the one eruption into two, it was the fourth largest known to science.
"The Yellowstone volcano's previous behavior is the best guide of what it will do in the future," says Ben Ellis, co-author and post-doctoral researcher at Washington State University's School of the Environment. "This research suggests explosive volcanism from Yellowstone is more frequent than previously thought."
 
The new ages for each Huckleberry Ridge eruption reduce the volume of the first event to 2,200 cubic kilometers, roughly 12 percent less than previously thought. A second eruption of 290 cubic kilometers took place more than 6,000 years later.
 
That first eruption still deserves to be called "super," as it is one of the largest known to have occurred on Earth and darkened the skies with ash from southern California to the Mississippi River. By comparison, the 1980 eruption of Mount St. Helens produced 1 cubic kilometer of ash. The larger blast of Oregon's Mount Mazama 6,850 years ago produced 116 cubic kilometers of ash.
 
The study, funded by the National Science Foundation and published in the June issue of the Quaternary Geochronology, used high-precision argon isotope dating to make the new calculations. The radioactive decay rate from potassium 40 to argon 40 serves as a "rock clock" for dating samples and has a precision of .2 percent. Darren Mark, co-author and a post-doctoral research fellow at the SUERC, recently helped fine tune the technique and improve it by 1.2 percent—a small-sounding difference that can become huge across geologic time.
 
"Improved precision for greater temporal resolution is not just about adding another decimal place to a number,  says Mark. "It's far more exciting. It's like getting a sharper lens on a camera. It allows us to see the world more clearly."
 
The project asks the question: Might super-eruptions actually be products of multiple, closely spaced eruptions through time? With improved temporal resolution, in times to come, maybe super-eruptions will be not quite so super.
 
 

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[californiadisasters] On This Date In CA Weather History (April 30)



1988: An earthquake 46 miles west of San Diego generated large surf of 14 feet with sets to 20 feet.
It is unknown if this was a tsunami.

1981: It was 82° in Big Bear Lake, the highest temperature on record for April.

1981: All-time record high for the month of April in Bakersfield, 101°.

1951: Record low of 37° at Fresno, frost observed in some outlying areas.

Source: NWS Hanford & San Diego

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[californiadisasters] On This Date In CA Weather History (April 29)



2006: A major rockslide closed Highway 140 about 6 miles southwest of El Portal (middle entrance to Yosemite).

1980: The Padres' home game against the Atlanta Braves was rained out at (then) Jack Murphy Stadium.
This also occurred the previous day on 4.28.1980.

1951: Thunderstorms produced hail damaging crops, especially plums, in the Fresno area.

Source: NWS Hanford & San Diego

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[californiadisasters] On This Date In CA Weather History (April 28)



2005: Funnel clouds were reported in Hemet and in Carlsbad.

2005:
Severe thunderstorms in the afternoon hours dropped hail as large as 1.25 inches in diameter in Kings County damaging crops, including 20 percent of the cherry crop.
In Parlier, 3.57" of rain fell and a number of streets were flooded in Fresno.
North of Visalia a funnel cloud was spotted and photographed.

2004: It was 85° in Idyllwild, the highest temperature on record for April.
This also occurred the previous day on 4.27 and on 4.3.1961.

1999: Heavy thunderstorm rains reduced visibility on I-10 between Fontana and Colton and caused 57 traffic accidents involving 212 vehicles.
81 were injured.
Property damage and costs of emergency services were estimated at more than $1 million.

1983: The Angels' home game at Anaheim Stadium against the Detroit Tigers was rained out.

1980: The Padres' home game against the Atlanta Braves was rained out at (then) Jack Murphy Stadium.
This also occurred the next day on 4.29.1980.

1970: Santa Barbara set a montly record low of 30°.

1962: Wind gusts of 45 to 60 mph near Mojave caused blowing sand that dropped visibility, halted traffic and causing some damage to vehicles.

1960: Heavy rain that began on 4.27 ended on this day (across SoCal).
One drowning death and three traffic deaths resulted.
Flooding closed highways.

1948: A severe dust storm struck Kern County described as "the worst ever" at the time on record.
Visibility was near zero throughout the day.
Crop damage was extensive and there were numerous traffic accidents.
Bakersfield had sustained south-southeast winds of 40 mph.
.

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[californiadisasters] On This Date In CA Weather History (April 27)



2004: It was 85° in Idyllwild, the highest temperature on record for April.
This also occurred the next day on 4.28 and on 4.3.1961.
Record highs for April were also set on 4.26, when it was 103° at the Wild Animal Park and 100° at Yorba Linda.

1996: It was 98° in Victorville, the highest temperature on record for April.

1970: The Padres' home game against the Montreal Expos was rained out at (then) San Diego Stadium.
It was the first rainout in Padres history (since April 1969).

1967: A tornado touched down in the south end of the city of Madera.

1960: Heavy rain that began on this day ended on 4.28 (across SoCal).
One drowning death and three traffic deaths resulted. Flooding closed highways.

NWS Hanford & San Diego

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[Geology2] Images of Earth from above





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[Geology2] Meteor Hunters Strike Pay Dirt



A different kind of rush hits California's Gold Country after the recent shower of rocks from space, which scientists crave and can fetch $1,000 a gram.

COLOMA-LOTUS VALLEY, Calif — In the week since a fireball shot across the sky and exploded, scattering a rare type of meteorite over California's Gold Country, these hills have drawn a new rush of treasure seekers.

Once again there are lively saloons, fortune hunters jockeying for prime spots and astounding tales of luck — including that of Brenda Salveson, a local who found a valuable space rock while walking her dog Sheldon, named after the theoretical physicist on the TV show "The Big Bang Theory."

It started April 22, Earth Day, with a blazing streak across a morning sky and a sonic boom that the next day had the older women in the "Gentle Stretching to Beautiful Music" class at Sierra Ballet comparing notes on how hard their windows shook.

Eight hundred miles away, while windows were still rattling, Robert Ward in Prescott, Ariz., was getting alerts. A 35-year-old professional meteorite hunter and dealer, he pays for tips and keeps a bag packed, ready to go anywhere in the world to chase a meteorite.

On Tuesday, after 16 hours of driving, he scanned a parking lot in Lotus in the pre-dawn not knowing what type of rock he was seeking. But when he spotted a dark space pebble, he immediately recognized it as carbonaceous chondrite, meteorites containing water and carbon — the type scientists long to study for insights into how life began on Earth and possibly in other places.

"I was trembling," Ward said. "It's the rarest of the rare. It's older than the sun. It holds the building blocks of life."

The rush was on. The meteorites are invaluable to science but on the open market can also fetch $1,000 a gram, or more for larger, pristine pieces.

In Vancouver, Canada, Paul Gessler, a part-time meteorite hunter, was readying for a halibut fishing tournament when he read about Ward's find on a hobbyists Twitter feed. He took his fishing rod back to the house and told his wife he was driving to California.

At the NASA Ames Research Center north of San Jose, Beverly Girten, deputy director in charge of the center's experiments on the International Space Station, announced she was going to Coloma. Her boss reminded her of a conference call about a $40-million budget. Girten said meteorites with organic compounds could prove more important to science.

In the Gold Rush town of Rescue (elevation and population both 1,400), Salveson, a wife and mother of two, read a local news article about the meteorites. The area scattered with them, about three miles wide and 10 miles long, included Henningsen Lotus Park, where she walks her dog every morning. She noted what to look for: a rock that seemed out of place — different from anything around it. It would be dark and delicate.

On Wednesday, near the end of her stroll with Sheldon, Salveson picked up a rock the size of a spool of thread that seemed to match the description.

She walked over to a group with metal detectors.

"I opened my hand and they all let out a collective gasp," she said.

The geologists, as they turned out to be, wrapped the 17-gram stone in foil and told Salveson to get it into a bank vault.

A few minutes before, a firefighter had stopped to search at the park on his way to work and found a 2-gram meteorite in less than 20 minutes. A dealer paid him $2,000 on the spot.

Before going to the bank, Salveson made one stop: Rescue Elementary School. She had her children — Linnea, 10, and Tommy, 6 — and their classmates put their hands behind their backs. She pulled back the foil just a little and told them to look at perhaps the oldest thing anyone has ever seen.

Girten believes that should any of those children grow up to take a college earth science class, they might study this meteorite. Until now, the most studied meteorite has been the Murchison, found after a witnessed shower in Australia in 1969. All indications are that the Sutter's Mill meteorite will replace it as the meteorite most known by name to anyone in science.

"We want to learn about this asteroid," said Peter Jenniskens, an astronomer and senior research scientist at the Carl Sagan Center at the SETI (Search for Extraterrestrial Intelligence) Institute and the NASA Lunar Science Institute. "This is scientific gold."

But the time window to get the clues from outer space into a lab is small.

Source: http://www.latimes.com/news/local/la-me-meteorite-search-20120501,0,5730445.story

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RE: [Geology2] Ammonites Found Mini Oases at Ancient Methane Seeps



Thanks for the good wishes.  Yep still here with a couple of minor (I think) leftovers. 

 

Back helping part time with the juniors at school in the science and maths class.  Covered  the inner solar system and asteroid belt last week.  They were all very bright and I had trouble keeping up with them LOL  (10 and 11 year olds)

 

Rog

 

 

 

From: geology2@yahoogroups.com [mailto:geology2@yahoogroups.com] On Behalf Of LadyTozi@aol.com
Sent: 30 April 2012 03:53
To: geology2@yahoogroups.com
Subject: Re: [Geology2] Ammonites Found Mini Oases at Ancient Methane Seeps

 

 

Sorry to hear of your stroke, but glad that you are still with us and almost back to normal.

 

Bre



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Sunday, April 29, 2012

Re: [Geology2] Ammonites Found Mini Oases at Ancient Methane Seeps



Sorry to hear of your stroke, but glad that you are still with us and almost back to normal.

Bre


-----Original Message-----
From: roger.steinberg <roger.steinberg@btinternet.com>
To: geology2 <geology2@yahoogroups.com>
Sent: Sat, Apr 21, 2012 12:08 pm
Subject: RE: [Geology2] Ammonites Found Mini Oases at Ancient Methane Seeps

 
Hi Guys and Gals
Won't be able to read much of your news for a few days.  Just spent the last week in local Hospital with a stroke.  Our hospital is in the south east of England in a place called Southend On Sea and is the 4th best Stroke unit in the UK and 10th best globally (they tell me) Rather it was 1st best but they seem to have extended my time on this globe and I am almost back to normal.  I am limited on the pooter but will download and save what I can of your contributions for future reads
 
Cheers
 
Roger. S
 


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[californiadisasters] Anniversary Reminder



Reminder from:   californiadisasters Yahoo! Group
 
Title:   1992 Los Angeles Riots
 
Date:   Sunday April 29, 2012
Time:   5:00 pm - 5:00 pm
Repeats:   This event repeats every year.
Location:   Los Angeles
Notes:   Between 5 P.M. and 6 P.M. on this date in 1992 the Los Angeles Riots began in two places.
One was out in front of Parker Center (LAPD HQ) in downtown L.A. where an at-first peaceful protest turned violent.
The other location was at the corner of Florence and Normandy when an angry crowd developed and was not immediately dispersed by the LAPD who withdrew instead.
The situation subsequently cascaded out of control from both locations ultimately lasting three days.
Over the three days of rioting 53 people were killed and 2,000 injured and nearly a billion dollars in losses were incurred, most if it in the neighborhoods of the rioters.
 
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Yahoo! Shopping:   Browse Yahoo! Shopping Gift Guide
 
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Saturday, April 28, 2012

[californiadisasters] Anniversary Reminder



Reminder from:   californiadisasters Yahoo! Group
 
Title:   1996 Grand Fire
 
Date:   Saturday April 28, 2012
Time:   12:00 pm - 12:00 pm
Repeats:   This event repeats every year.
Location:   Ventura County
Notes:   On this date in 1996 the Grand Fire began in eastern Ventura County near Fillmore.

Driven by strong Santa Ana Winds it pushed across the southern face of the Topatopa Mountains above Fillmore and scorched 10,925 acres and damaged some orchards to the north of Highway 126.

Southern California Edison was found liable for damages as the fire was deemed to be caused by one of their powerlines interacting with inadquately trimmed branches.
Later in 1996 they would get in trouble again for the same thing relating to the problem as it related to the Calabasas (Malibu) Fire.
 
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Friday, April 27, 2012

[Volcano_Vista_HS] Volcano Vista HS Prom, 4/28/2012, 8:00 pm



Reminder from:   Volcano_Vista_HS Yahoo! Group
 
Title:   Volcano Vista HS Prom
 
Date:   Saturday April 28, 2012
Time:   8:00 pm - 11:00 pm
Location:   ABQ Convention Center
 
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[californiadisasters] Emergency Manager’s Weekly Report 4-27-12

Hello Everyone,

This week's edition is now available at one of the following websites:
• Weekly Report Yahoo Group (http://groups.yahoo.com/group/emweeklyreport/files/)
• Florida Emergency Preparedness Association Yahoo Group (http://finance.groups.yahoo.com/group/fepalist/files/)
• Daily Brief Yahoo Group (http://health.groups.yahoo.com/group/DailyBrief/files/)
• California Disasters Yahoo Group (http://groups.yahoo.com/group/californiadisasters/files/)

Emergency Manager's Weekly Report Table of Contents:
• Executive Summary (Page 4)
• Mad Cow Disease (Page 10)
• Emergency Management (Page11)
• Homeland Security, Defense and National Security (Page 13)
• Campus Safety and Security (Page 15)
• Functional Needs (Page 16)
• Hazard Research and News (Page 17)
• Public Safety Communications, Interoperability, 3-1-1 and 9-1-1 News (Page 19)
• Other (Page 20)
• Civil Preparedness, Security and Humanitarian Affairs (Page 21)
• Hazard Research and News (Page 23)
• International Affairs (Page 24)
• Climate Change News (Page 25)
• Alternate Energy Research and Development News (Page 26)
• Reports (Page 27)
• Additional Information (Page 28)

Steve Detwiler




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Thursday, April 26, 2012

[Volcano_Vista_HS] DONATIONS NEEDED for the Staff Appreciation Luncheon (Friday, May 4)



Your Volcano Vista Parent Advisory group is sponsoring a staff appreciation lunch and is in need of baked cookies or cookie bars (brownies, layered bars etc.) for next Friday, May 4th.

Cookies/Bars need to be delivered to the school by 10:15 am that Friday.

If you have any questions call Jacque at 450-9811 or email her at jacque@larsenfamily.com



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[Geology2] Fwd: Student researcher spies odd lava spirals on Mars



INTERESTING
Mars' geologic history

Begin forwarded message:

Subject: Student researcher spies odd lava spirals on Mars
Date: April 26, 2012 3:56:02 PM EDT

These twisty volcanic patterns can be found on Hawaii's Big Island and in the Pacific seafloor on our planet. While evidence for lava flows is present in many places on Mars, none are shaped like this latest find.

"I was quite surprised and puzzled when I first saw the coils," Andrew Ryan, a graduate student at Arizona State University, said in an email. He reported the discovery in Friday's issue of the journal Science.

The biggest surprise? The largest Martian lava spiral measured 100 feet across — bigger than any on Earth. It is further evidence that Mars was volcanically active recently — geologically speaking within the past 20 million years.

For more than a decade, scientists debated whether this maze of valleys near the Martian equator was sculpted by ice or volcanic processes.

As part of a class project last year, Ryan analyzed about 100 high-resolution photos of the region snapped by the Mars Reconnaissance Orbiter, which has been photographing the Martian surface since 2006. One evening, while taking a second look at the images, Ryan zoomed in and noticed the lava coils. He counted 269 spirals ranging from 16 feet to 100 feet across.

Ryan said he was not surprised the features were overlooked in the past since they blended in with the terrain. The coils looked strikingly similar to Hawaiian lava flows, leading Ryan to conclude that lava — not ice — was the driving force.

Planetary scientist David Paige of the University of California, Los Angeles, said the new work provides convincing evidence that the curious patterns were forged from volcanic activity.

This "illustrates just how complicated Mars' geologic history appears to really be," Paige wrote in an email. He was not part of the research team.

It's believed that rivers of molten lava flowed through the Martian valleys into a broad basin where they settled and formed the coil shapes. The spiral shapes were preserved as the lava cooled.

There are no clear signs that the region today is volcanically active. With more observations, Ryan said it is possible lava coils may exist elsewhere on the red planet.




Read more…




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[Geology2] Fwd: Volcano Eruption - South-America - Ecuador



Tungurahua - Ecuador

Begin forwarded message:

Damage level: Moderate

Description:

Over the weekend, the Tungurahua's volcanic eruption had a strong explosion that caused gravel to fall down in the nearby town of Pillate, Ecuador. The explosion, characterized by its loud "cannon ball shot", was immediately detected by locals and scientists observing the volcano's progress. The explosion was later followed by a slight tremor and a constant pulsation of "high energy" said reports. The constant cloud coverage surrounding the volcano has caused scientists, from the Geophysical Institute branch of the National Polytechnic School to have trouble determining its current state. Most of the direct observations are conducted in the Guadalupe Observatory, the closest in the vicinity. Tungurahua, located in the Andes Mountains in Ecuador, is 5,016 meters high and its eruptions began in 1999. Since then, the volcano has transitioned from times of high activity and those of calm. 

However, Tungurahua is not the only volcano causing extreme damage and concern in the Hispanic world. Popocatpetl, located in Mexico City, has also been under close watch due to its recent activity which included ash blasts.



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[Geology2] Splatters of Molten Rock Signal Period of Intense Asteroid Impacts On Earth




This image shows an artist's depiction of a 10-kilometer (six-mile) diameter asteroid striking the Earth. Approximately 70 of these dinosaur killer-sized or larger impacts hit the Earth over a span that lasted between 3.8 and 1.8 billion years ago. They are capable of producing a global millimeter- to centimeter-thick rock layer that contains impact debris: sand-sized droplets, or spherules, of molten rock that rained down from the huge molten plumes made by the mega-impact. (Credit: Art by Don Davis)

Splatters of Molten Rock Signal Period of Intense Asteroid Impacts On Earth

ScienceDaily (Apr. 25, 2012) — New research reveals that the Archean era -- a formative time for early life from 3.8 billion years ago to 2.5 billion years ago -- experienced far more major asteroid impacts than had been previously thought, with a few impacts perhaps even rivaling those that produced the largest craters on the Moon, according to a paper recently published online in Nature.

The fingerprints of these gigantic blasts are millimeter- to centimeter-thick rock layers on Earth that contain impact debris: sand-sized droplets, or spherules, of molten rock that rained down from the huge molten plumes thrown up by mega-impacts. This barrage of asteroids appears to have originated in an extended portion of the inner asteroid belt that is now mostly extinct. Computer models suggest the zone was likely destabilized about 4 billion years ago by the late migration of the giant planets from the orbits they formed on to where we find them today.

The team conducting this study includes members or associates of the NASA Lunar Science Institute's Center of Lunar Origin and Evolution (CLOE), based at the Southwest Research Institute (SwRI) in Boulder, Colo.

Archean rocks are scarcer than rocks of any other age, and impact spherule beds have been found only in terrains where conditions were ideal for capture and preservation, such as in shales deposited on the seafloor below the reach of waves. At least 12 spherule beds deposited between 3.47 and 1.7 billion years ago (Ga) have been found, with most in the Archean; 7 between 3.23-3.47 Ga, 4 between 2.49-2.63 Ga and 1 between 1.7-2.1 Ga.

"The beds speak to an intense period of late bombardment of the Earth, but their source has long been a mystery," says CLOE Principal Investigator and SwRI Researcher Dr. William Bottke.

By comparison, the Chicxulub impact that is believed to have killed the dinosaurs 65 million years ago was the only known collision over the past half-billion years that made a spherule layer as thick as those of the Archean period.

"The Archean beds contain enough extraterrestrial material to rule out alternative sources for the spherules, such as volcanoes," says Bruce Simonson, a geologist from the Oberlin College and Conservatory who has studied these ancient layers for decades.

The timing of these major events is curious because they occur well after the presumed end of the so-called Late Heavy Bombardment, or LHB, of the Moon. This period occurred about 4 billion years ago and produced the largest lunar craters, or basins. The precise nature of the LHB continues to be debated, and testing what happened and for how long was the top science priority for future exploration of the Moon, according to a previously published report by the National Research Council.

The best available model of the LHB, often referred to as the Nice model after the observatory where it was developed in Nice, France, invokes a large-scale repositioning of the giant planets Jupiter, Saturn, Uranus and Neptune as a trigger for a solar system-wide bombardment of asteroids and comets. The extensive pummeling of the Earth and Moon identified in the Nice model, however, lasted 100- to 200-million years, not nearly long enough to explain the Archean spherule beds.

Following up on the implications of the Nice model, the team examined a possible missing source of impactors, one that would have come from the inner edge of the main asteroid belt between the orbits of Mars and Jupiter. While most of this region is now unstable, researchers believe this may not have been the case 4 billion years ago. The difference was that the giant planets, whose gravitational forces control the orbital stability of solar system worlds, were likely in a more compact configuration than they are now. By creating a hypothetical extension to the primordial asteroid belt and tracking what would have happened to these bodies when the giant planets reorganized themselves, team members found the bodies could have delivered numerous big impactors to the Earth and Moon over a much longer time. As additional validation of the model, team members found it could reproduce a tiny population of asteroids called the Hungarias, a reservoir of relatively stable but fairly small asteroids located between the orbits of Mars and the inner edge of the main asteroid belt.

They found that approximately 70 (and 4) dinosaur killer-sized or larger impacts hit the Earth (and Moon) over a span that lasted between 3.8 and 1.8 billion years ago. The frequency of these impacts was enough to reproduce the known impact spherule beds. It also hints at the possibility that the enormous 180-300-kilometer (112-186-mile) diameter Vredefort crater in South Africa, which is 2 billion years old, and the nearly 250-kilometer (155-mile) Sudbury crater in Canada, which is 1.85 billion years old, might be literally the last gasp of the LHB on Earth.

Team members predict that the largest Archean-era impacts should be similar to the 15 or so youngest and largest lunar basins, which range in diameter from about 300-1,200 kilometers (186-746-miles). The implication of such enormous impacts over the Archean era is unknown, but some are believed to have released nearly 500 times the blast energy of the Chicxulub impact.

"It will be interesting to see whether these mammoth events affected the evolution of early life on our planet or our biosphere in important ways," says Bottke.

In a companion paper also published online April 25 in Nature, another team of researchers, led by Brandon Johnson and Jay Melosh of Purdue University, used computer models to estimate the gargantuan projectile sizes needed to explain the nature and distribution of the Archean spherule layers. Their work provides experimental data to correlate with this study.

Funding for this study was provided by the NASA Lunar Science Institute, the Grant Agency of the Czech Republic and Germany's Helmholtz Alliance.



Story Source:

The above story is reprinted from materials provided by Southwest Research Institute.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. William F. Bottke, David Vokrouhlick√Ĺ, David Minton, David Nesvorn√Ĺ, Alessandro Morbidelli, Ramon Brasser, Bruce Simonson, Harold F. Levison. An Archaean heavy bombardment from a destabilized extension of the asteroid belt. Nature, 2012; DOI: 10.1038/nature10967

Southwest Research Institute (2012, April 25). Splatters of molten rock signal period of intense asteroid impacts on Earth. ScienceDaily. Retrieved April 26, 2012, from http://www.sciencedaily.com­ /releases/2012/04/120425140312.htm

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