Navigation Links
AGU journal highlights -- Mar. 26, 2013
Date:3/26/2013

ss extinction. Evidence for the asteroid impact comes from sediments in the K-Pg boundary layer, but the details of the event, including what precisely caused the mass extinction, are still being debated.

Some scientists have hypothesized that since the ejecta from the impact would have heated up dramatically as it reentered the Earth's atmosphere, the resulting infrared radiation from the upper atmosphere would have ignited fires around the globe and killed everything except those animals and plants that were sheltered underground or underwater.

Other scientists have challenged the global fire hypothesis on the basis of several lines of evidence, including absence of charcoal-which would be a sign of widespread fires-in the K-Pg boundary sediments. They also suggested that the soot observed in the debris layer actually originated from the impact site itself, not from widespread fires caused by reentering ejecta.

Robertson et al. show that the apparent lack of charcoal in the K-Pg boundary layer resulted from changes in sedimentation rates: When the charcoal data are corrected for the known changes in sedimentation rates, they exhibit an excess of charcoal, not a deficiency. They also show that the mass of soot that could have been released from the impact site itself is far too small to account for the observed soot in the K-Pg layer. In addition, they argue that since the physical models show that the radiant energy reaching the ground from the reentering ejecta would be sufficient to ignite tinder, it would thereby spark widespread fires. The authors also review other evidence for and against the firestorm hypothesis and conclude that all of the data can be explained in ways that are consistent with widespread fires.

Source:
Journal of Geophysical Research-Planets, doi:10.1002/jgrg.20018, 2013

Contact: Kate Ramsayer
kramsayer@agu.org
202-777-7524
American Geophysical Union
Source:Eurekalert

Page: 1 2 3 4 5 6 7 8 9

Related biology news :

1. Frontiers announces launch of new open-access journal, Frontiers in Public Health
2. Elsevier announces the launch of a new journal: Wound Medicine
3. News tips from the journal mBio®, volume 4, issue 1
4. 66 titles join Wileys journal portfolio in 2013
5. Genetics Society of Americas Genetics journal highlights for March 2013
6. Elsevier announces the launch of a new journal: Methods in Oceanography
7. Georgia Physicians Study Published in The Journal of Urology
8. Established journals to publish under open access model
9. The Geological Society of America Journal Geology: Dynamic geoscience
10. Elsevier announces the launch of a new journal: Journal of Forensic Radiology and Imaging
11. Elsevier announces the launch of a new journal: Anthropocene
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/27/2014)... deadly disease that exists as five strains, none of ... strains is the Sudan ebolavirus (SUDV). Although not the ... illness, even as recently as 2012. In a new ... , researchers now report a possible therapy that could ... Dye, Sachdev Sidhu, Jonathan Lai and colleagues explain that ...
(Date:8/27/2014)... have largely succeeded in sidelining the use of ... its potential contributions to Americans, health conditions. But ... best way to assuage the nation,s insatiable sweet ... & Engineering News (C&EN), the weekly news ... the article, Stephen Ritter, a senior correspondent at ...
(Date:8/27/2014)... bacterium that can be found in both unprocessed and ... in Denmark have been infected with Listeria ... , The bacterium is notoriously difficult to fight because ... changes in its surroundings, says Associate Professor Birgitte Kallipolitis, ... Department of Biochemistry and Molecular Biology, she has published ...
Breaking Biology News(10 mins):Potential therapy for the Sudan strain of Ebola could help contain some future outbreaks 2Researchers discover why Listeria bacterium is so hard to fight 2Researchers discover why Listeria bacterium is so hard to fight 3
... . The conditioning Works of Sierra Nevada,s ski ... researchers of the University of Granada (Spain) have ... species in order to suggest new mechanisms for vegetable cover ... biodiversity in the National Park of Sierra Nevada . ...
... French . , A novel x-ray technique allowing ... reached before has been developed by a team of researchers ... Results of the research led by Professor Majed Chergui, head ... FEMTO group at PSI appear online December 11 in the ...
... on the environment have reduced populations of wild ... more apparent than in worldwide fisheries, where thanks ... populations of fish are on the brink of ... dire situation, captive breeding, the controlled breeding of ...
Cached Biology News:An essay proves that vegetation could recover in the ski resort of Sierra Nevada 2Molecules in the spotlight 2
(Date:8/27/2014)... -- Rhythm, a biopharmaceutical company developing peptide therapeutics that ... metabolic disorders, announced today that it has filed a ... and Exchange Commission (SEC) relating to the proposed initial ... number of shares to be offered and the price ... Citigroup and Cowen and Company will act ...
(Date:8/27/2014)... The Global and China Trifluoroacetic Acid ... current state of the Trifluoroacetic Acid industry in Global ... of the industry, including definitions, applications and industry chain ... are provided with a focus on history, developments, trends ... the international and Chinese situation is also offered. , ...
(Date:8/27/2014)... “We are honored to be named to this ... of Radiant Sage. “We are offering truly ground-breaking clinical ... market to a different level. We are enabling ... and effectively manage the massive amounts of medical imaging ... read by trained physicians. Being recognized by technology industry ...
(Date:8/27/2014)... , Aug. 27, 2014 Research ... "Global Stable Isotope Ratio Mass Spectrometer Industry Report 2014" ... Global Stable Isotope Ratio Mass Spectrometer Industry Report 2014 ... state of the global isotope ratio mass spectrometer industry. ... the industry including definitions, classifications, applications and industry chain ...
Breaking Biology Technology:Rhythm Files Registration Statement for Proposed Initial Public Offering 2Trifluoroacetic Acid Industry (Asia, Europe, North America, ROW) Analysis Report Now Available at ReportsnReports.com 2Radiant Sage Named to CIOReview List of 100 Most Promising Technology Companies 2Global Stable Isotope Ratio Mass Spectrometer Industry Report 2014 2
... Web-software services provider Zywave Inc. recently announced it ... being constructed in the Milwaukee County Research Park . ... real estate development circles, but the news is more than ... playing out, and an example of how a powerful business ...
... - Public officials on both sides of the ... during Republican and Democratic administrations, but judging by the ... the Joint Committee on Finance , there is ... ,That division was illustrated this week when Joint Finance, ...
... Wis. - Small Tree Communications , a ... million defense contract for continued development of communications technology. ... appropriations bill, was awarded through a competitive award process. ... communications capabilities for the United States Army . ...
Cached Biology Technology:Corporate venturing can nurture software success 2Corporate venturing can nurture software success 3Corporate venturing can nurture software success 4Corporate venturing can nurture software success 5Corporate venturing can nurture software success 6GOP, Dems split over funding of state technology projects 2GOP, Dems split over funding of state technology projects 3GOP, Dems split over funding of state technology projects 4
... kit, 110 to 220 V, enables ... doubles flow rates and valve capacity ... kit includes the Maximizer base unit, ... tubing kit, system cable 30, and ...
... pen has been designed to provide a thin film-like ... on a slide. This barrier creates the proper ... target area on the slide. PAP Pen contains ... acetone. It can be removed, if desired, by ...
... any scanner into a gel densitometer. Although ... the basic operation simply consists of converting ... into pixel density / intensity values through ... Turn your scanner into a high speed ...
Anti-Conjugated Quinaldic Acid...
Biology Products: