There's no doubt this brazen, beautiful Javan leopard is a male, and he doesn't show any obvious signs of stress ? despite being recently added to the Red List of endangered species.
This prima donna Panthera pardus melas was caught relaxing by a camera trap in Indonesia's Mount Halimun Salak National Park by Age Kridalaksana, an ecologist working with the Center for International Forestry Research.
You can see the leopard come to life in a time-lapse video created from the camera images. Kridalaksana and his colleagues hope to use their new-found knowledge of the big cat's range to work out how best to manage his habitat.
The number of leopards on Java is estimated at 250 to 700, and on average each animal prowls a range of about 1000 hectares. But the island is losing 2000 hectares of rainforest each year to loggers and other causes, and the national park itself has already lost a quarter of its original area ? it's now down to 113,000 hectares. "If their habitat continues to shrink, they could face increasing competition for food and shelter," says Ken Sugimura, head of the project.
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
Have your say
Only subscribers may leave comments on this article. Please log in.
Only personal subscribers may leave comments on this article
Subscribe now to comment.
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.
YOSEMITE NATIONAL PARK, Calif. (AP) ? Federal investigators probing the hantavirus outbreak blamed for three deaths at Yosemite National Park recommended on Monday that design changes to tent cabins and other privately run lodging first be reviewed by National Park Service officials.
The report released by the Interior Department's Office of Inspector General found that park officials responded to last summer's outbreak appropriately and within department policy.
"When the outbreak was identified, NPS mobilized to contain and remediate the outbreak and to prevent further outbreaks," Mary Kendall, a deputy inspector general, wrote in a letter attached to the report.
Still, the report found that current policy didn't require park officials to approve design changes made to the "Signature tent cabins" by concessionaire Delaware North Companies Parks and Resorts, which added rafters and wall studs to the structures.
Investigators determined that deer mice, which can carry the illness, nested inside the double walls of the new tents in Yosemite's family friendly Curry Village.
At least eight of the nine tourists who fell ill stayed in the tent cabins.
Because the changes to the cabins were considered routine maintenance, current park service policy did not require prior approval, the report found.
The report also recommended that the park service begin cyclical pest monitoring and inspections of all public accommodations.
While there is a current pest monitoring program at Yosemite, Delaware North was responsible for Curry Village, which was not considered at high risk for hantavirus.
The company issued a statement late Monday saying it would follow the recommendations in the report.
"DNC Parks & Resorts at Yosemite has consistently worked hand-in-hand with the National Park Service and public health officials on this issue," spokeswoman Lisa Cesaro said in the statement. "The Signature Tent Cabins have been removed from Curry Village. We are following the recommendations by the National Park Service, which were developed in consultation with the California Department of Public Health and the Centers for Disease Control and Prevention."
Prior to the outbreak, Delaware only responded to pests in the cabins when visitors or housekeeping staff complained, the report said.
Treatment with A1-PI slows the progression of emphysema in Alpha-1 antitrypsin deficiencyPublic release date: 21-May-2013 [ | E-mail | Share ]
Contact: Nathaniel Dunford ndunford@thoracic.org American Thoracic Society
ATS 2013, PHILADELPHIA?Treatment with an Alpha-1 proteinase inhibitor (A1-PI), a naturally occurring protein that protects lung tissue from breakdown and protects the lung's elasticity, is effective in slowing the progression of emphysema in patients with Alpha-1 antitrypsin deficiency (AATD), a life-threatening genetic disorder, according to a new study presented at the 2013 American Thoracic Society International Conference.
The study showed the efficacy of A1-PIin preventing the loss of lung tissue as measured by computed tomography (CT) scan lung density at full inspiration (TLC), which is a more sensitive measure of disease progression than conventional parameters.This is the first prospective study to demonstrate the efficacy and safety of augmentation therapy in a randomized, placebo-controlled trial using this parameter.
"Our experience of the last quarter century has been that augmentation therapy is associated with better preserved lung function and reduced mortality, " said lead author Kenneth R. Chapman, M.D., director of the Asthma and Airway Centre of the University Health Network, in Toronto. "This randomized, placebo-controlled trial using a sensitive measure of lung density adds the most rigorous evidence to date that augmentation therapy slows the progression of emphysema in patients with Alpha-1 antitrypsin deficiency. The effect of A1-PI seen in this trial was both clinically and statistically significant, finally confirming its benefit in preventing the loss of lung tissue in patients with this potentially debilitating disease."
Chapman added that preliminary data from an extension trial suggest that early treatment with A1-PIshows persistent efficacy in patients with AATD and emphysema. In both the A1-PI and placebo groups who elected to continue treatment withA1-PI 60 mg/kg weekly, the benefit in CT scan lung density decline continued.
AATD is a hereditary condition that can severely affect a patient's lung function. The condition is marked by a low level or absence of A1-PI, a natural protein that protects the lung from breakdown by inhibiting neutrophil elastase, and protects lung elasticity. AATD can lead to emphysema at a young age (
There is no cure for AATD, but there are treatments for the symptoms of the disease, including bronchodilators and inhaled steroids, which help open the airways. Augmentation therapy, which is administered intravenously, has been shown to slow or halt the destruction of lung tissue in AATD.
The current trial, the largest clinical trial of this treatment to date, was a randomized, placebo-controlled, double-blind, multinational, multicenter phase III/IV study comparing the efficacy and safety ofA1-PIwith placebo in 180 subjects with emphysema due to AATD. Patients received A1-PIintravenously 60 mg/kg weekly or matching placebo over two years. The effect ofA1-PI on the progression of emphysema, the primary endpoint of the study, was assessed by the decline of lung density, measured by CT scan. Key secondary endpoints included changes in exercise capacity, symptoms score and rate of pulmonary exacerbations over two years.
There was no difference between groups in baseline characteristics: mean age 53.1 +/- 7.4 year; forced expiratory volume in 1 second (FEV1) 48.9 +/- 11.7%. According to study findings, the annual rate of lung density loss was significantly less in A1-PI-treated patients (-1.45 +/- 0.24 units vs. -2.19 +/-0.25 units; p = 0.017, one sided). Secondary outcome variables and the few adverse reactions reported were not significantly different between groups.
"The augmentation treatment used in the current study is not known to have a role in emphysema caused by tobacco smoking unrelated to alpha-1 antitrypsin deficiency, and our findings apply to a particular type of genetically-related emphysema," said Dr. Chapman. "Furthermore, our findings show preservation, but not restoration, of lung tissue. That is, the treatment slows the damage for people with alpha-1 antitrypsin deficiency but does not repair the damage."
"Although augmentation therapy has been well accepted in the United States, it has been slow to gain acceptance in other countries where augmentation therapy may be unavailable and/or unfunded. Our positive findings may encourage more widespread use of this treatment," said Dr. Chapman.
"With 2013 marking the 50th anniversary of the discovery of Alpha-1 antitrypsin deficiency, we are excited to now have confirmation of the clinical efficacy of this therapy in reducing the loss of lung tissue in Alpha-1 patients who have emphysema, " said Gerry McElvaney, professor of medicine at Royal College of Surgeons of Ireland, and principal investigator of the trial.
###
* Please note that numbers in this release may differ slightly from those in the abstract. Many of these investigations are ongoing; the release represents the most up-to-date data available at press time.
Abstract 45385
IV Alpha1 Antitrypsin (A1AT) Preserves Lung Density In Homozygous Alpha1 Antitrypsin Deficiency (A1ATD); A Randomized, Placebo-Controlled Trial
Authors: K.R. Chapman1, J.G.W. Burdon2, E. Piitulainen3, R.A. Sandhaus4, N. Seersholm5, J.M. Stocks6, L. Huang7, J.M. Edelman7, N.G. McElvaney8; 1University Health Network - Toronto/CA, 2St. Vincent's Hospital - Melbourne, VIC/AU, 3Lund University - Malmo/SE, 4National Jewish Health - Denver, CO/US, 5Gentofte Hospital - Hellerup/DK, 6University of Texas Health Science Center at Tyler - Tyler, TX/US, 7CSL Behring - King Of Prussia, PA/US, 8Beaumont Hospital, Royal College of Surgeons in Ireland - Dublin/IE; RAPID Trial Study Group
Abstract Body
Background: Observational studies show slower rates of lung function decline and decreased mortality in A1ATD patients receiving IV augmentation with purified A1AT but efficacy in slowing emphysema progression has not been confirmed by a randomized, placebo-controlled trial. CT scan measured lung density is a more sensitive measure of disease progression in A1ATD emphysema than conventional lung function parameters and is a biomarker of response to therapy. Methods: In a multi-center, multi-national trial, we randomized patients with homozygous A1ATD (ZZ) to receive A1AT (Zemaira, CSL Behring) intravenously 60 mg/kg weekly or placebo over 2 years, measuring CT scan lung density at baseline, 3 months, 1 and 2 years. Secondary endpoints included spirometry, KCO, shuttle walk and reported adverse events. Results: There was no difference between groups in baseline characteristics: mean age 53.1 +/- 7.4 (SD) yr; FEV1 48.9 +/- 11.7 (SD) %; KCO 31.7 +/- 5.8 (SD) %. Of 180 patients randomized (98 men, 82 women), 153 completed the trial (84/93 A1AT, 69/87 placebo, p=0.04). The annual rate of lung density loss was significantly less in A1AT-treated patients (-1.45 +/- 0.24 units vs. -2.19 +/-0.25 units; p = 0.017, one-sided). Secondary outcome variables and adverse events were not significantly different between groups. There was 1 death in the A1AT group and 3 in the placebo group. Conclusions: Purified A1AT augmentation IV slowed the progression of emphysema as measured by CT scan lung density, a more sensitive measure of disease progression in AATD emphysema than conventional lung function parameters. This is the first prospective study demonstrating the efficacy and safety of augmentation therapy in a randomized, placebo-controlled trial using this parameter.
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Treatment with A1-PI slows the progression of emphysema in Alpha-1 antitrypsin deficiencyPublic release date: 21-May-2013 [ | E-mail | Share ]
Contact: Nathaniel Dunford ndunford@thoracic.org American Thoracic Society
ATS 2013, PHILADELPHIA?Treatment with an Alpha-1 proteinase inhibitor (A1-PI), a naturally occurring protein that protects lung tissue from breakdown and protects the lung's elasticity, is effective in slowing the progression of emphysema in patients with Alpha-1 antitrypsin deficiency (AATD), a life-threatening genetic disorder, according to a new study presented at the 2013 American Thoracic Society International Conference.
The study showed the efficacy of A1-PIin preventing the loss of lung tissue as measured by computed tomography (CT) scan lung density at full inspiration (TLC), which is a more sensitive measure of disease progression than conventional parameters.This is the first prospective study to demonstrate the efficacy and safety of augmentation therapy in a randomized, placebo-controlled trial using this parameter.
"Our experience of the last quarter century has been that augmentation therapy is associated with better preserved lung function and reduced mortality, " said lead author Kenneth R. Chapman, M.D., director of the Asthma and Airway Centre of the University Health Network, in Toronto. "This randomized, placebo-controlled trial using a sensitive measure of lung density adds the most rigorous evidence to date that augmentation therapy slows the progression of emphysema in patients with Alpha-1 antitrypsin deficiency. The effect of A1-PI seen in this trial was both clinically and statistically significant, finally confirming its benefit in preventing the loss of lung tissue in patients with this potentially debilitating disease."
Chapman added that preliminary data from an extension trial suggest that early treatment with A1-PIshows persistent efficacy in patients with AATD and emphysema. In both the A1-PI and placebo groups who elected to continue treatment withA1-PI 60 mg/kg weekly, the benefit in CT scan lung density decline continued.
AATD is a hereditary condition that can severely affect a patient's lung function. The condition is marked by a low level or absence of A1-PI, a natural protein that protects the lung from breakdown by inhibiting neutrophil elastase, and protects lung elasticity. AATD can lead to emphysema at a young age (
There is no cure for AATD, but there are treatments for the symptoms of the disease, including bronchodilators and inhaled steroids, which help open the airways. Augmentation therapy, which is administered intravenously, has been shown to slow or halt the destruction of lung tissue in AATD.
The current trial, the largest clinical trial of this treatment to date, was a randomized, placebo-controlled, double-blind, multinational, multicenter phase III/IV study comparing the efficacy and safety ofA1-PIwith placebo in 180 subjects with emphysema due to AATD. Patients received A1-PIintravenously 60 mg/kg weekly or matching placebo over two years. The effect ofA1-PI on the progression of emphysema, the primary endpoint of the study, was assessed by the decline of lung density, measured by CT scan. Key secondary endpoints included changes in exercise capacity, symptoms score and rate of pulmonary exacerbations over two years.
There was no difference between groups in baseline characteristics: mean age 53.1 +/- 7.4 year; forced expiratory volume in 1 second (FEV1) 48.9 +/- 11.7%. According to study findings, the annual rate of lung density loss was significantly less in A1-PI-treated patients (-1.45 +/- 0.24 units vs. -2.19 +/-0.25 units; p = 0.017, one sided). Secondary outcome variables and the few adverse reactions reported were not significantly different between groups.
"The augmentation treatment used in the current study is not known to have a role in emphysema caused by tobacco smoking unrelated to alpha-1 antitrypsin deficiency, and our findings apply to a particular type of genetically-related emphysema," said Dr. Chapman. "Furthermore, our findings show preservation, but not restoration, of lung tissue. That is, the treatment slows the damage for people with alpha-1 antitrypsin deficiency but does not repair the damage."
"Although augmentation therapy has been well accepted in the United States, it has been slow to gain acceptance in other countries where augmentation therapy may be unavailable and/or unfunded. Our positive findings may encourage more widespread use of this treatment," said Dr. Chapman.
"With 2013 marking the 50th anniversary of the discovery of Alpha-1 antitrypsin deficiency, we are excited to now have confirmation of the clinical efficacy of this therapy in reducing the loss of lung tissue in Alpha-1 patients who have emphysema, " said Gerry McElvaney, professor of medicine at Royal College of Surgeons of Ireland, and principal investigator of the trial.
###
* Please note that numbers in this release may differ slightly from those in the abstract. Many of these investigations are ongoing; the release represents the most up-to-date data available at press time.
Abstract 45385
IV Alpha1 Antitrypsin (A1AT) Preserves Lung Density In Homozygous Alpha1 Antitrypsin Deficiency (A1ATD); A Randomized, Placebo-Controlled Trial
Authors: K.R. Chapman1, J.G.W. Burdon2, E. Piitulainen3, R.A. Sandhaus4, N. Seersholm5, J.M. Stocks6, L. Huang7, J.M. Edelman7, N.G. McElvaney8; 1University Health Network - Toronto/CA, 2St. Vincent's Hospital - Melbourne, VIC/AU, 3Lund University - Malmo/SE, 4National Jewish Health - Denver, CO/US, 5Gentofte Hospital - Hellerup/DK, 6University of Texas Health Science Center at Tyler - Tyler, TX/US, 7CSL Behring - King Of Prussia, PA/US, 8Beaumont Hospital, Royal College of Surgeons in Ireland - Dublin/IE; RAPID Trial Study Group
Abstract Body
Background: Observational studies show slower rates of lung function decline and decreased mortality in A1ATD patients receiving IV augmentation with purified A1AT but efficacy in slowing emphysema progression has not been confirmed by a randomized, placebo-controlled trial. CT scan measured lung density is a more sensitive measure of disease progression in A1ATD emphysema than conventional lung function parameters and is a biomarker of response to therapy. Methods: In a multi-center, multi-national trial, we randomized patients with homozygous A1ATD (ZZ) to receive A1AT (Zemaira, CSL Behring) intravenously 60 mg/kg weekly or placebo over 2 years, measuring CT scan lung density at baseline, 3 months, 1 and 2 years. Secondary endpoints included spirometry, KCO, shuttle walk and reported adverse events. Results: There was no difference between groups in baseline characteristics: mean age 53.1 +/- 7.4 (SD) yr; FEV1 48.9 +/- 11.7 (SD) %; KCO 31.7 +/- 5.8 (SD) %. Of 180 patients randomized (98 men, 82 women), 153 completed the trial (84/93 A1AT, 69/87 placebo, p=0.04). The annual rate of lung density loss was significantly less in A1AT-treated patients (-1.45 +/- 0.24 units vs. -2.19 +/-0.25 units; p = 0.017, one-sided). Secondary outcome variables and adverse events were not significantly different between groups. There was 1 death in the A1AT group and 3 in the placebo group. Conclusions: Purified A1AT augmentation IV slowed the progression of emphysema as measured by CT scan lung density, a more sensitive measure of disease progression in AATD emphysema than conventional lung function parameters. This is the first prospective study demonstrating the efficacy and safety of augmentation therapy in a randomized, placebo-controlled trial using this parameter.
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
One reason the Internet has become so popular thing to use is because of how easy it is to reach out or share things with other individuals. This is extremely beneficial for new business online. Read the following article for article advertising tips and techniques which can help you boost your business.
Set aside the AP style guide for the most part and focus on crafting interesting articles that are a conversational tone. Doing so will make your articles.You need to use the AP rules because they help create content that works great, but reduce restrictions for better search engine rankings.
Make your paragraphs short, so they are easier to read. It is important to streamline your article syndication endeavors if you make sure that not absolutely essential in getting your main message across.
If you?re not able to spend the time writing articles, time or skill to write articles, consider hiring someone to write the articles for you. Although having someone write for you will cost you money, you need to remember that your time is also worth money and that professionally written articles can dramatically increase the amount of traffic your website receives.
Wrap it up with a compelling call to action. Your readers will be more likely to act if you have made it easy to see how to do so.
Be careful when listening to people that claim to be experts in article advertising. That doesn?t mean their advice they provide is faulty.It just means that you shouldn?t take everything they say as the gospel truth.
You can engage a reader by starting the article with a joke. Just make sure that you are telling an appropriate and applies to the topic at hand.
The best article promotion campaigns have their own style and tone. Good writers let their personalities clear with their writing style.
While you will probably want to hit a certain word count with your articles, it is not something you should worry about when you do a first draft. The author?s own mind should have a sense about how lengthly the article should be. It is possible to trim the article during editing, or even chop a long article into two distinct pieces.
Unless your articles are intentionally purged by websites, they will remain on the web indefinitely, and can continue to refer some traffic to your site. You also use an article as a means of promoting other articles; this will gradually expand your network and glean followers.
Make sure that content actually match the topic you are covering. Search engines will eventually notice that your search rankings.
Each article should use between 500 and around 4 sentences per paragraph. Most article directories have this same criteria, and applying it to your writings will ease the distribution of the articles. You should make a good target is 300-400 words.
If you make articles that people will want to read, you?ll have a clear advantage. Articles that provide ?how to? information or diagrams are always popular.
Write your own words and not someone else?s. Don?t try to sound like an article if you find yourself running to a novice. Readers have the ability to tell that it isn?t your true voice in the writing style and the entire content might be judged as false.
The most important aspect of article submission is to have content that is unique. Google tends to rank newer articles which have something new to say higher than reprints. You needn?t spend a fortune on writing articles; there are many writers out there who work cheaply to provide you the content creation.
Automation is the best way to engage in article marketing and having spare time. There are many different programs that able capable of helping you; you just have to find one which meets your needs.Compare these applications and you can find one best suits your needs.
If you did not know about article advertising before, then you probably found this article to be of great help. You?ll discover that some of these concepts are simply common sense. It?s not magic and it?s certainly not a gimmick. These tips are perfectly legitimate?you just needed some help finding it!
WASHINGTON (AP) ? The president and CEO of The Associated Press says the government's seizure of AP journalists' phone records was "unconstitutional" and already has had a chilling effect on newsgathering.
Gary Pruitt says the Justice Department's secret subpoena of reporters' phone records has made sources less willing to talk to AP journalists.
The Justice Department disclosed the seizure of two months of phone records in a letter the AP received May 10. The letter did not state a reason, but prosecutors had said they were conducting a leaks investigation into how the AP learned about an al-Qaida bomb plot in Yemen before it was made public last year. Pruitt said the AP story contradicted the government's claim at the time there was no terrorist plot.
New in GEOLOGY: Gems, Darwin, Mars, Hemp, Snowball Earth, a Siberian Impact Crater, and MorePublic release date: 20-May-2013 [ | E-mail | Share ]
Contact: Christa Stratton cstratton@geosociety.org Geological Society of America
Boulder, Colo., USA New Geology articles posted online ahead of print 9 and 16 May 2013 cover a wide swath of geoscience subdisciplines, including minerals exploration, archaeology, planetary geology, tectonics, oceanography, geophysics, and paleobotany. Locations studied include Siberia; the Sumatran subduction margin; the Monte Arsiccio mine at Alpi Apuane, Italy; Ukraine; Mars; and the Southeastern U.S. Atlantic Margin. Brief highlights follow:
1. Rubies, jadeite, and plate tectonics;
2. The clear fingerprint of ice ages left on coral reefs around the world;
3. The history of human activities related to hemp;
4. Glaciers on Mars;
5. The "mush model" and a deepening in geoscientists' understanding of silicic magma systems;
6. A call for a cautious use of ocean sediments in developing past histories of major earthquakes.
7. Analysis of orebodies of the Monte Arsiccio mine, Italy;
8. Major targets for mineral exploration;
9. High-frequency, climatically controlled sea-level changes;
10. The pollen record in lake sediments from the Boltysh meteorite impact crater in Ukraine;
11. Ediacaran glaciation in Siberia and snowball Earth;
12. The first evidence for widespread seabed methane venting along the southeastern U.S.; and
13. Nano- to micro-scale frictional processes.
Highlights are provided below. GEOLOGY articles published ahead of print can be accessed online at http://geology.gsapubs.org/content/early/recent. All abstracts are open-access at http://geology.gsapubs.org/; representatives of the media may obtain complimentary GEOLOGY articles by contacting Kea Giles at the address above.
Please discuss articles of interest with the authors before publishing stories on their work, and please make reference to GEOLOGY in articles published. Contact Kea Giles for additional information or assistance.
Non-media requests for articles may be directed to GSA Sales and Service, gsaservice@geosociety.org.
Plate tectonic gemstones
Robert J. Stern, Geosciences Dept., The University of Texas at Dallas, Richardson, Texas 75083-0688, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34204.1.
Humans have used, sought, and traded gemstones for thousands of years, uniquely linking art, economics, and geology, from the dawn of civilization until now. In contrast, the theory of plate tectonics, which explains how Earth's crust and upper mantle is divided into independent plates, has only existed for about 50 years. Gemstones mostly form where special conditions of pressure, temperature, and chemical composition occur, and sometimes these conditions can be linked to plate tectonic processes. Plate boundaries are dynamic geologic environments where conditions for gemstone formation occur, especially at convergent plate boundaries, where plates are subducted, sinking back into Earth's interior. In this paper, a team of U.S., Japanese, and Canadian geoscientists identify two gemstones -- ruby and a type of jade (jadeite) -- that form at two types of convergent plate boundaries, in subduction zones and where continents collide. Jadeite forms where seafloor (oceanic crust) is subducted -- for example, around the Pacific Ocean, in Central America, New Zealand, and SE Asia. In contrast, ruby forms where two continents collide, for example now beneath the Himalayas, where India and Asia are colliding, and in east Africa, where east and west Gondwana collided 550 million years ago. This new understanding of "plate tectonic gemstones" provides a new perspective on how plate tectonics functions and also suggests fresh ways to look for new deposits of these gemstones.
Profiles of ocean island coral reefs controlled by sea-level history and carbonate accumulation rates
Michael Toomey et al., Geology and Geophysics Dept., Woods Hole Oceanographic Institution, 360 Woods Hole Road, MS#22, Woods Hole, Massachusetts 02543, USA; and Dept. of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34109.1.
Coral reefs around islands develop a wide variety of forms, including narrow platforms fringing the coast, barrier reefs encircling deep lagoons, and flights of terraces that have been raised above or drowned deep below the sea surface. Charles Darwin, who was also a geologist, suggested that reefs take on a fixed sequence of forms as a volcanic island gradually sinks below sea level. Reefs on some island chains, such as the Society Islands, appear to follow this sequence, but Darwin's idea cannot explain much of the diversity of reef forms found around the world, such as the reefs of the Hawaiian Islands. In addition to island sinking, reefs are shaped by the interaction of coral growth, wave erosion, and sea level changes. In this study, Michael Toomey and colleagues use a computer simulation of reef development to understand these interactions, and compare their results with a global compilation of rates of coral growth and island sinking or uplift. They find that large sea-level cycles driven by ice ages have left a clear fingerprint on coral reefs around the world, and that Darwin's proposed sequence of reef forms only develops in a small subset of environments.
Sedimentary cannabinol tracks the history of hemp retting
Marlne Lavrieux et al., Institut des Sciences de la Terre d'Orlans, Universit d'Orlans, ISTO, UMR 7327, 45071 Orlans, France; CNRS/INSU, ISTO, UMR 7327, 45071 Orlans, France; and BRGM, ISTO, UMR 7327, BP 36009, 45060 Orlans, France. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34073.1.
Hemp (Cannabis sp.) has been a fundamental plant for the development of human societies. Its fibers have long been used for textiles and rope making, which requires prior stem retting. This process is essential for extracting fibers from the stem of the plant but can adversely affect the quality of surface waters. The history of human activities related to hemp (its domestication, spread, and processing) is frequently reconstructed from seeds and pollen detected in archaeological sites or in sedimentary archives, but this method does not always make it possible to ascertain whether retting took place. Hemp is also known to contain phytocannabinoids, a type of chemicals that is specific to the plant. One of these chemicals, cannabinol (CBN), was discovered in a sediment record from a lake in the French Massif Central and was shown to be related to retting. This molecule tracks the hemp retting history in the area during the last 800 years and brings information about its induced water pollution. These findings, supported by pollen analyses and historical data, show that this novel sedimentary tracer can help to better constrain past impacts of human activities on the environment.
Evidence for Hesperian glaciation along the Martian dichotomy boundary
Alfonso F. Davila et al., SETI Institute, Mountain View, California 94043, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34201.1.
Alfonso F. Davila and colleagues analyzed images and topographic data from the Aeolis Mensae region of Mars. Their analyses indicate that these terrains were eroded by glaciers emanating from the Martian dichotomy boundary. Collectively, our observations suggest that glacial activity could have been an important mechanism of modification of equatorial regions on Mars for three billion years.
The longevity of large upper crustal silicic magma reservoirs
Sarah E. Gelman et al., Dept. of Earth and Space Sciences, University of Washington, Seattle, Washington 98195, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34241.1.
Using numerical heat transfer models, Sarah E. Gelman and colleagues simulated the incremental assembly of upper crustal silicic magma reservoirs, the source of Earth's largest volcanic eruptions. Incorporating reasonable magma emplacement rates, complexity in thermal properties, and appropriate igneous phase diagrams, they demonstrate that these large reservoirs can remain continuously active for more than a million years in highly productive magmatic environments, while remaining more transient in lower flux regions. These results are consistent with volcanological, geochronological, and geophysical data obtained from various provinces (e.g., Taupo Volcanic Zone and the Southern Rocky Mountain Volcanic Field as long-lived, productive regions, while the Cascades arc hosts lower flux stratovolcanoes). This work supports recent models emphasizing the role of in situ upper crustal magma storage and differentiation in a crystal-rich environment ("mush zones"). This is a particularly provocative deepening in geoscientists' understanding of silicic magma systems because previous thermal modeling studies, which have incorporated fewer complexities than those addressed in this study, have been used as primary evidence against the "mush model." The results presented here are consistent with natural observations from multiple techniques and represent an important contribution toward predicting how and where large reservoirs can grow.
Can turbidites be used to reconstruct a paleoearthquake record for the central Sumatran margin?
Esther J. Sumner et al., Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, Hampshire SO14 3ZH, UK. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34298.1.
Large earthquakes are known to sometimes trigger huge underwater slides and flows of sediment in the oceans. An increasingly widespread technique is to sample these sediments, date them, and thereby infer the recurrence times of past major earthquakes that can be used in hazard assessment for future earthquakes. In this new study, Esther J. Sumner and colleagues tested whether large earthquakes reliably generate the types of deposit needed to reconstruct a complete and accurate earthquake record. They did this by analyzing the seafloor sediment record on the Sumatran subduction margin, in a region that experienced the third largest earthquake yet recorded in 2004 and numerous other large magnitude earthquakes in historical times. The seafloor sediment record offshore Sumatra reveals surprisingly little evidence for sediment slides and flows related to known large magnitude earthquakes. Therefore, large earthquakes on the Sumatran margin do not always trigger the large slides and flows of sediment necessary for reconstructing a complete and accurate history of major earthquakes. Until a better understanding is reached about why some seafloor slopes are more prone to widespread failure in the event of an earthquake, we suggest cautious use of ocean sediments in developing past histories of major earthquakes.
Mobilization of Tl-Hg-As-Sb-(Ag, Cu)-Pb sulfosalt melts during lowgrade metamorphism in the Alpi Apuane (Tuscany, Italy)
C. Biagioni et al. (M. D'Orazio, corresponding), Dipartimento di Scienze della Terra, Universit di Pisa, Via Santa Maria 53, 56126 Pisa, Italy. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34211.1.
C. Biagioni and colleagues have discovered an exceptional assemblage of Tl-Hg-As-Sb-(Ag,Cu)-Pb sulfosalt minerals, showing textural evidence for their mobilization as melts in the barite-pyrite-iron oxide orebodies of the Monte Arsiccio mine (Alpi Apuane, Tuscany, Italy). The relative abundance of rare thallium sulfosalts (including three new mineral species), their peculiar textural features within the orebodies (e.g., migration along matrix grain boundaries, drop-like internal textures, low interfacial angles between sulfosalts and matrix minerals), and the overall high thallium content in pyrite from the entire mining district (up to ~900 ppm), make the barite-pyrite-iron oxide deposits of the Alpi Apuane a reference locality for studying very low-temperature sulfosalt melts in low-grade metamorphic complexes (greenschist facies). This study reveals how sulfosalt melting during low-grade regional metamorphism controls the redistribution of economically valuable and environmentally critical elements such as thallium (a highly toxic element) in sulfide orebodies containing significant amounts of low-melting-point chalcophile elements. The increase in local concentration combined with the change in thallium speciation (from trace level substituting ion to essential constituent element) could significantly influence the environmental release of thallium during weathering of such complex ore deposits.
Magmatic-hydrothermal processes within an evolving Earth: Iron oxide-copper-gold and porphyry Cu Mo Au deposits
Jeremy P. Richards, Dept. of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada; and A. Hamid Mumin, Dept. of Geology, Brandon University, 270 18th Street, Brandon, Manitoba R7A 6A9, Canada. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34275.1.
Copper and gold commonly occur together in two deposit types known as porphyry copper (plus or minus gold and molybdenum) and iron oxide-copper-gold (IOCG) deposits. Porphyry deposits are characterized by abundant iron-sulfide minerals, whereas IOCG deposits are characterized by abundant iron-oxide minerals. Both deposit types are major targets for mineral exploration. The origin of porphyry deposits is relatively well established (they are formed from hydrothermal fluids exsolved from magmas emplaced at shallow levels in the crust, in tectonic settings related to subduction of oceanic plates). The origin of IOCG deposits is more widely debated, but several aspects of their nature and mode of formation are similar to porphyry deposits, including their key metal contents, formation by hydrothermal fluids arguably exsolved from magmas, and broad tectonic association. However, IOCG deposits are more common in ancient (Precambrian, older than or about equal to 550 million years old) rocks, whereas porphyry deposits are most abundant in younger (Phanerozoic, younger than or about equal to 550 million years old) rocks. Study authors Jeremy P. Richards and colleagues propose that this temporal distribution is related to established oxygenation of the deep oceans at the end of the Precambrian, which for the first time introduced abundant seawater-derived sulfur into subduction zones, and led to the predominance of sulfide-rich porphyry deposits in the Phanerozoic.
Orbital-scale climate change and glacioeustasy during the early Late Ordovician (pre-Hirnantian) determined from ?18O values in marine apatite
M. Elrick et al., Earth & Planetary Sciences Dept., University of New Mexico, Albuquerque, New Mexico 87131, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34363.1.
Results from this study by M. Elrick and colleagues suggest that 10 million years before the well-documented Latest Ordovician glaciation and mass extinction event, there were significant continental glaciers growing and melting and causing global sea levels to rise and fall on 104-105 year time scales. These high-frequency, climatically controlled sea-level changes resulted in the development of widespread subtropical sedimentary cycles and changes in the oxygen isotope values of marine apatite occurring within the cycles. These high-frequency climate and sea-level oscillations support the interpretation of a dynamic and prolonged Ordovician greenhouse to icehouse transition.
A high-resolution nonmarine record of an early Danian hyperthermal event, Boltysh crater, Ukraine
Iain Gilmour et al., Planetary and Space Sciences, Dept. of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34292.1.
Lake sediments from the Boltysh meteorite impact crater in Ukraine record geochemical and pollen evidence for a brief period of global warming a short time after the boundary that marks the extinction of the dinosaurs. The 24-km-diameter Boltysh crater, which formed a few thousand years before its much larger and more famous cousin at Chicxulub, which is thought to be responsible for the mass extinction at the end of the Cretaceous, quickly filled with lake sediments. These sediments provide the first record on land of a brief period of warming and major perturbation of the carbon cycle previously found only in marine sediments. This indicates a global change in the Earth's climate. Plant pollens record a change in the flora around the crater that shows an increasingly warm and dry climate over a period of up to 340 thousand years, while carbon isotopes show that this coincides with a major perturbation in Earth's carbon cycle. Together they reveal that profound environmental change continued to occur on a global scale shortly after the dramatic events surrounding the Chicxulub impact.
Testing the snowball Earth hypothesis for the Ediacaran
Alexei V. Ivanov et al., Institute of the Earth's Crust, Siberian Branch, Russian Academy of Sciences, Lermontov Street 128, Irkutsk 664033, Russia. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34345.1.
Earth experienced ultimately cold climates several times in its history, such as glaciers reaching the tropical latitudes, and the ocean probably stayed completely frozen. This type of climate stage is known as snowball Earth. Siberia was once tropical during the Ediacaran period about 580-570 million years ago, yet it was glaciated. If Earth was at the snowball stage and thus completely covered by ice, the ice prevented accumulation of cosmic dust and micrometeorites at oceanic floor. The dust and micrometeorite particles would have accumulated rapidly on the ocean floor at the ice-melting event, providing a geochemical signal. However, unlike a previous Cryogenian glaciation at about 635 million years ago, which is a classic example of the snowball Earth conditions, Alexei Ivanov and colleagues find this signal to be at a background level, suggesting that Ediacaran glaciation recorded in Siberia did not reach the snowball Earth stage. The severe cold climate and open oceans probably were prerequisites for evolution of metazoan and a later burst of life on Earth.
Evidence for extensive methane venting on the southeastern U.S. Atlantic margin
L.L. Brothers et al., U.S. Geological Survey, 384 Woods Hole Road, Woods Hole, Massachusetts 02543, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34217.1.
Results reported here by L.L. Brothers and colleagues show the first evidence for widespread seabed methane venting along the southeastern U.S. Atlantic Margin beyond the well-known Blake Ridge Diapir Seep. While it was suspected that such seeps existed, there was little direct evidence until now. Data collected from recent ship and autonomous underwater vehicle surveys discovered multiple water-column gas plumes (>1000 m height and made up of bubbles). Brothers and colleagues also mapped extensive new chemosynthetic seep communities (communities of biological organisms that directly use methane and/or sulfide for life processes) at the Blake Ridge and Cape Fear Diapirs. Flow along these systems is both more dynamic (more active) and more widespread than previously believed.
Dynamic weakening by nanoscale smoothing during high-velocity fault slip
Xiaofeng Chen et al. (Ze'ev Reches, corresponding), School of Geology and Geophysics, University of Oklahoma, Norman, Oklahoma 73019, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34169.1.
While slip during large earthquakes occurs along faults that are hundreds of kilometers long, the dynamic weakening that drives these earthquakes is controlled by nano- to micro-scale frictional processes. Xiaofeng Chen and colleagues analyzed the nano- to micro-scale friction processes along experimental faults that slipped at high slip-velocity. Their analysis showed that the experimental faults became very smooth and developed shiny, mirror surfaces. The nanoscale friction coefficient dropped on these highly smooth surfaces and demonstrated, for the first time, that slip-smoothing at high slip-velocities can be an effective mechanism of dynamic weakening.
###
http://www.geosociety.org
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
New in GEOLOGY: Gems, Darwin, Mars, Hemp, Snowball Earth, a Siberian Impact Crater, and MorePublic release date: 20-May-2013 [ | E-mail | Share ]
Contact: Christa Stratton cstratton@geosociety.org Geological Society of America
Boulder, Colo., USA New Geology articles posted online ahead of print 9 and 16 May 2013 cover a wide swath of geoscience subdisciplines, including minerals exploration, archaeology, planetary geology, tectonics, oceanography, geophysics, and paleobotany. Locations studied include Siberia; the Sumatran subduction margin; the Monte Arsiccio mine at Alpi Apuane, Italy; Ukraine; Mars; and the Southeastern U.S. Atlantic Margin. Brief highlights follow:
1. Rubies, jadeite, and plate tectonics;
2. The clear fingerprint of ice ages left on coral reefs around the world;
3. The history of human activities related to hemp;
4. Glaciers on Mars;
5. The "mush model" and a deepening in geoscientists' understanding of silicic magma systems;
6. A call for a cautious use of ocean sediments in developing past histories of major earthquakes.
7. Analysis of orebodies of the Monte Arsiccio mine, Italy;
8. Major targets for mineral exploration;
9. High-frequency, climatically controlled sea-level changes;
10. The pollen record in lake sediments from the Boltysh meteorite impact crater in Ukraine;
11. Ediacaran glaciation in Siberia and snowball Earth;
12. The first evidence for widespread seabed methane venting along the southeastern U.S.; and
13. Nano- to micro-scale frictional processes.
Highlights are provided below. GEOLOGY articles published ahead of print can be accessed online at http://geology.gsapubs.org/content/early/recent. All abstracts are open-access at http://geology.gsapubs.org/; representatives of the media may obtain complimentary GEOLOGY articles by contacting Kea Giles at the address above.
Please discuss articles of interest with the authors before publishing stories on their work, and please make reference to GEOLOGY in articles published. Contact Kea Giles for additional information or assistance.
Non-media requests for articles may be directed to GSA Sales and Service, gsaservice@geosociety.org.
Plate tectonic gemstones
Robert J. Stern, Geosciences Dept., The University of Texas at Dallas, Richardson, Texas 75083-0688, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34204.1.
Humans have used, sought, and traded gemstones for thousands of years, uniquely linking art, economics, and geology, from the dawn of civilization until now. In contrast, the theory of plate tectonics, which explains how Earth's crust and upper mantle is divided into independent plates, has only existed for about 50 years. Gemstones mostly form where special conditions of pressure, temperature, and chemical composition occur, and sometimes these conditions can be linked to plate tectonic processes. Plate boundaries are dynamic geologic environments where conditions for gemstone formation occur, especially at convergent plate boundaries, where plates are subducted, sinking back into Earth's interior. In this paper, a team of U.S., Japanese, and Canadian geoscientists identify two gemstones -- ruby and a type of jade (jadeite) -- that form at two types of convergent plate boundaries, in subduction zones and where continents collide. Jadeite forms where seafloor (oceanic crust) is subducted -- for example, around the Pacific Ocean, in Central America, New Zealand, and SE Asia. In contrast, ruby forms where two continents collide, for example now beneath the Himalayas, where India and Asia are colliding, and in east Africa, where east and west Gondwana collided 550 million years ago. This new understanding of "plate tectonic gemstones" provides a new perspective on how plate tectonics functions and also suggests fresh ways to look for new deposits of these gemstones.
Profiles of ocean island coral reefs controlled by sea-level history and carbonate accumulation rates
Michael Toomey et al., Geology and Geophysics Dept., Woods Hole Oceanographic Institution, 360 Woods Hole Road, MS#22, Woods Hole, Massachusetts 02543, USA; and Dept. of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34109.1.
Coral reefs around islands develop a wide variety of forms, including narrow platforms fringing the coast, barrier reefs encircling deep lagoons, and flights of terraces that have been raised above or drowned deep below the sea surface. Charles Darwin, who was also a geologist, suggested that reefs take on a fixed sequence of forms as a volcanic island gradually sinks below sea level. Reefs on some island chains, such as the Society Islands, appear to follow this sequence, but Darwin's idea cannot explain much of the diversity of reef forms found around the world, such as the reefs of the Hawaiian Islands. In addition to island sinking, reefs are shaped by the interaction of coral growth, wave erosion, and sea level changes. In this study, Michael Toomey and colleagues use a computer simulation of reef development to understand these interactions, and compare their results with a global compilation of rates of coral growth and island sinking or uplift. They find that large sea-level cycles driven by ice ages have left a clear fingerprint on coral reefs around the world, and that Darwin's proposed sequence of reef forms only develops in a small subset of environments.
Sedimentary cannabinol tracks the history of hemp retting
Marlne Lavrieux et al., Institut des Sciences de la Terre d'Orlans, Universit d'Orlans, ISTO, UMR 7327, 45071 Orlans, France; CNRS/INSU, ISTO, UMR 7327, 45071 Orlans, France; and BRGM, ISTO, UMR 7327, BP 36009, 45060 Orlans, France. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34073.1.
Hemp (Cannabis sp.) has been a fundamental plant for the development of human societies. Its fibers have long been used for textiles and rope making, which requires prior stem retting. This process is essential for extracting fibers from the stem of the plant but can adversely affect the quality of surface waters. The history of human activities related to hemp (its domestication, spread, and processing) is frequently reconstructed from seeds and pollen detected in archaeological sites or in sedimentary archives, but this method does not always make it possible to ascertain whether retting took place. Hemp is also known to contain phytocannabinoids, a type of chemicals that is specific to the plant. One of these chemicals, cannabinol (CBN), was discovered in a sediment record from a lake in the French Massif Central and was shown to be related to retting. This molecule tracks the hemp retting history in the area during the last 800 years and brings information about its induced water pollution. These findings, supported by pollen analyses and historical data, show that this novel sedimentary tracer can help to better constrain past impacts of human activities on the environment.
Evidence for Hesperian glaciation along the Martian dichotomy boundary
Alfonso F. Davila et al., SETI Institute, Mountain View, California 94043, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34201.1.
Alfonso F. Davila and colleagues analyzed images and topographic data from the Aeolis Mensae region of Mars. Their analyses indicate that these terrains were eroded by glaciers emanating from the Martian dichotomy boundary. Collectively, our observations suggest that glacial activity could have been an important mechanism of modification of equatorial regions on Mars for three billion years.
The longevity of large upper crustal silicic magma reservoirs
Sarah E. Gelman et al., Dept. of Earth and Space Sciences, University of Washington, Seattle, Washington 98195, USA. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34241.1.
Using numerical heat transfer models, Sarah E. Gelman and colleagues simulated the incremental assembly of upper crustal silicic magma reservoirs, the source of Earth's largest volcanic eruptions. Incorporating reasonable magma emplacement rates, complexity in thermal properties, and appropriate igneous phase diagrams, they demonstrate that these large reservoirs can remain continuously active for more than a million years in highly productive magmatic environments, while remaining more transient in lower flux regions. These results are consistent with volcanological, geochronological, and geophysical data obtained from various provinces (e.g., Taupo Volcanic Zone and the Southern Rocky Mountain Volcanic Field as long-lived, productive regions, while the Cascades arc hosts lower flux stratovolcanoes). This work supports recent models emphasizing the role of in situ upper crustal magma storage and differentiation in a crystal-rich environment ("mush zones"). This is a particularly provocative deepening in geoscientists' understanding of silicic magma systems because previous thermal modeling studies, which have incorporated fewer complexities than those addressed in this study, have been used as primary evidence against the "mush model." The results presented here are consistent with natural observations from multiple techniques and represent an important contribution toward predicting how and where large reservoirs can grow.
Can turbidites be used to reconstruct a paleoearthquake record for the central Sumatran margin?
Esther J. Sumner et al., Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, Hampshire SO14 3ZH, UK. Posted online ahead of print 9 May 2013; http://dx.doi.org/10.1130/G34298.1.
Large earthquakes are known to sometimes trigger huge underwater slides and flows of sediment in the oceans. An increasingly widespread technique is to sample these sediments, date them, and thereby infer the recurrence times of past major earthquakes that can be used in hazard assessment for future earthquakes. In this new study, Esther J. Sumner and colleagues tested whether large earthquakes reliably generate the types of deposit needed to reconstruct a complete and accurate earthquake record. They did this by analyzing the seafloor sediment record on the Sumatran subduction margin, in a region that experienced the third largest earthquake yet recorded in 2004 and numerous other large magnitude earthquakes in historical times. The seafloor sediment record offshore Sumatra reveals surprisingly little evidence for sediment slides and flows related to known large magnitude earthquakes. Therefore, large earthquakes on the Sumatran margin do not always trigger the large slides and flows of sediment necessary for reconstructing a complete and accurate history of major earthquakes. Until a better understanding is reached about why some seafloor slopes are more prone to widespread failure in the event of an earthquake, we suggest cautious use of ocean sediments in developing past histories of major earthquakes.
Mobilization of Tl-Hg-As-Sb-(Ag, Cu)-Pb sulfosalt melts during lowgrade metamorphism in the Alpi Apuane (Tuscany, Italy)
C. Biagioni et al. (M. D'Orazio, corresponding), Dipartimento di Scienze della Terra, Universit di Pisa, Via Santa Maria 53, 56126 Pisa, Italy. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34211.1.
C. Biagioni and colleagues have discovered an exceptional assemblage of Tl-Hg-As-Sb-(Ag,Cu)-Pb sulfosalt minerals, showing textural evidence for their mobilization as melts in the barite-pyrite-iron oxide orebodies of the Monte Arsiccio mine (Alpi Apuane, Tuscany, Italy). The relative abundance of rare thallium sulfosalts (including three new mineral species), their peculiar textural features within the orebodies (e.g., migration along matrix grain boundaries, drop-like internal textures, low interfacial angles between sulfosalts and matrix minerals), and the overall high thallium content in pyrite from the entire mining district (up to ~900 ppm), make the barite-pyrite-iron oxide deposits of the Alpi Apuane a reference locality for studying very low-temperature sulfosalt melts in low-grade metamorphic complexes (greenschist facies). This study reveals how sulfosalt melting during low-grade regional metamorphism controls the redistribution of economically valuable and environmentally critical elements such as thallium (a highly toxic element) in sulfide orebodies containing significant amounts of low-melting-point chalcophile elements. The increase in local concentration combined with the change in thallium speciation (from trace level substituting ion to essential constituent element) could significantly influence the environmental release of thallium during weathering of such complex ore deposits.
Magmatic-hydrothermal processes within an evolving Earth: Iron oxide-copper-gold and porphyry Cu Mo Au deposits
Jeremy P. Richards, Dept. of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada; and A. Hamid Mumin, Dept. of Geology, Brandon University, 270 18th Street, Brandon, Manitoba R7A 6A9, Canada. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34275.1.
Copper and gold commonly occur together in two deposit types known as porphyry copper (plus or minus gold and molybdenum) and iron oxide-copper-gold (IOCG) deposits. Porphyry deposits are characterized by abundant iron-sulfide minerals, whereas IOCG deposits are characterized by abundant iron-oxide minerals. Both deposit types are major targets for mineral exploration. The origin of porphyry deposits is relatively well established (they are formed from hydrothermal fluids exsolved from magmas emplaced at shallow levels in the crust, in tectonic settings related to subduction of oceanic plates). The origin of IOCG deposits is more widely debated, but several aspects of their nature and mode of formation are similar to porphyry deposits, including their key metal contents, formation by hydrothermal fluids arguably exsolved from magmas, and broad tectonic association. However, IOCG deposits are more common in ancient (Precambrian, older than or about equal to 550 million years old) rocks, whereas porphyry deposits are most abundant in younger (Phanerozoic, younger than or about equal to 550 million years old) rocks. Study authors Jeremy P. Richards and colleagues propose that this temporal distribution is related to established oxygenation of the deep oceans at the end of the Precambrian, which for the first time introduced abundant seawater-derived sulfur into subduction zones, and led to the predominance of sulfide-rich porphyry deposits in the Phanerozoic.
Orbital-scale climate change and glacioeustasy during the early Late Ordovician (pre-Hirnantian) determined from ?18O values in marine apatite
M. Elrick et al., Earth & Planetary Sciences Dept., University of New Mexico, Albuquerque, New Mexico 87131, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34363.1.
Results from this study by M. Elrick and colleagues suggest that 10 million years before the well-documented Latest Ordovician glaciation and mass extinction event, there were significant continental glaciers growing and melting and causing global sea levels to rise and fall on 104-105 year time scales. These high-frequency, climatically controlled sea-level changes resulted in the development of widespread subtropical sedimentary cycles and changes in the oxygen isotope values of marine apatite occurring within the cycles. These high-frequency climate and sea-level oscillations support the interpretation of a dynamic and prolonged Ordovician greenhouse to icehouse transition.
A high-resolution nonmarine record of an early Danian hyperthermal event, Boltysh crater, Ukraine
Iain Gilmour et al., Planetary and Space Sciences, Dept. of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34292.1.
Lake sediments from the Boltysh meteorite impact crater in Ukraine record geochemical and pollen evidence for a brief period of global warming a short time after the boundary that marks the extinction of the dinosaurs. The 24-km-diameter Boltysh crater, which formed a few thousand years before its much larger and more famous cousin at Chicxulub, which is thought to be responsible for the mass extinction at the end of the Cretaceous, quickly filled with lake sediments. These sediments provide the first record on land of a brief period of warming and major perturbation of the carbon cycle previously found only in marine sediments. This indicates a global change in the Earth's climate. Plant pollens record a change in the flora around the crater that shows an increasingly warm and dry climate over a period of up to 340 thousand years, while carbon isotopes show that this coincides with a major perturbation in Earth's carbon cycle. Together they reveal that profound environmental change continued to occur on a global scale shortly after the dramatic events surrounding the Chicxulub impact.
Testing the snowball Earth hypothesis for the Ediacaran
Alexei V. Ivanov et al., Institute of the Earth's Crust, Siberian Branch, Russian Academy of Sciences, Lermontov Street 128, Irkutsk 664033, Russia. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34345.1.
Earth experienced ultimately cold climates several times in its history, such as glaciers reaching the tropical latitudes, and the ocean probably stayed completely frozen. This type of climate stage is known as snowball Earth. Siberia was once tropical during the Ediacaran period about 580-570 million years ago, yet it was glaciated. If Earth was at the snowball stage and thus completely covered by ice, the ice prevented accumulation of cosmic dust and micrometeorites at oceanic floor. The dust and micrometeorite particles would have accumulated rapidly on the ocean floor at the ice-melting event, providing a geochemical signal. However, unlike a previous Cryogenian glaciation at about 635 million years ago, which is a classic example of the snowball Earth conditions, Alexei Ivanov and colleagues find this signal to be at a background level, suggesting that Ediacaran glaciation recorded in Siberia did not reach the snowball Earth stage. The severe cold climate and open oceans probably were prerequisites for evolution of metazoan and a later burst of life on Earth.
Evidence for extensive methane venting on the southeastern U.S. Atlantic margin
L.L. Brothers et al., U.S. Geological Survey, 384 Woods Hole Road, Woods Hole, Massachusetts 02543, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34217.1.
Results reported here by L.L. Brothers and colleagues show the first evidence for widespread seabed methane venting along the southeastern U.S. Atlantic Margin beyond the well-known Blake Ridge Diapir Seep. While it was suspected that such seeps existed, there was little direct evidence until now. Data collected from recent ship and autonomous underwater vehicle surveys discovered multiple water-column gas plumes (>1000 m height and made up of bubbles). Brothers and colleagues also mapped extensive new chemosynthetic seep communities (communities of biological organisms that directly use methane and/or sulfide for life processes) at the Blake Ridge and Cape Fear Diapirs. Flow along these systems is both more dynamic (more active) and more widespread than previously believed.
Dynamic weakening by nanoscale smoothing during high-velocity fault slip
Xiaofeng Chen et al. (Ze'ev Reches, corresponding), School of Geology and Geophysics, University of Oklahoma, Norman, Oklahoma 73019, USA. Posted online ahead of print 16 May 2013; http://dx.doi.org/10.1130/G34169.1.
While slip during large earthquakes occurs along faults that are hundreds of kilometers long, the dynamic weakening that drives these earthquakes is controlled by nano- to micro-scale frictional processes. Xiaofeng Chen and colleagues analyzed the nano- to micro-scale friction processes along experimental faults that slipped at high slip-velocity. Their analysis showed that the experimental faults became very smooth and developed shiny, mirror surfaces. The nanoscale friction coefficient dropped on these highly smooth surfaces and demonstrated, for the first time, that slip-smoothing at high slip-velocities can be an effective mechanism of dynamic weakening.
###
http://www.geosociety.org
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Andrew Strauss warns England of Australian pace attack ? Cricket news
With almost a month to go before cricket?s oldest rivalry is reignited, the Ashes series, former England skipper Andrew Strauss has warned Alastair Cook and company of the Australian pace attack.
Strauss, the 36-year-old former England opener, who led England to a 3-1 series win the last time the Ashes rivals met in Australia in 2010-11, said on Friday that the Kangaroos have one of the best pace attacks in the world, including the likes of Peter
Siddle, Mitchell Starc, Ryan Harris and emerging seamer James Pattinson.
?They have got a really a really good bowling attack -- it will be interesting to see how Mitchell Starc goes over here,? said Strauss in an interview with Sky Sports at Lord?s.
The former English skipper, however, said that batting would be the tourists? weak link since most of the batsmen in the Australian Ashes squad do not have any idea of playing in English conditions.
?But the area where they are weakest, you'd say, is their batting. Some of these guys haven't played much in England before and there are a lot of left handers in there,? said the veteran of 100 Tests and 127 One Day Internationals.
?(England off-spinner) Graeme Swann will be licking his lips at the possibility of playing these guys on turning wickets,? added the former left-hander.
Asked to predict the result of the five-match series, the Transvaal-born ex-England cricketer said, ?It's going to be closely contested series - Ashes always are and this one will be no different.?
Strauss also hoped ace England batsman Kevin Pietersen to regain full fitness before the commencement of the Ashes series in July. Pietersen is currently nursing a knee injury he sustained in March 2013.
The Alastair Cook led Three Lions will begin their bid for a third Ashes victory in a row on July 10, 2013 at Trent Bridge, Nottingham. It may be noted here that the Poms have not lifted three Ashes urns in a row since 1950.
ABIDJAN, Ivory Coast (AP) ? A militia leader accused of grave crimes during Ivory Coast's 2010-11 postelection violence was taken into custody Saturday not far from the national park where his forces had been illegally occupying in the country's volatile western region, officials said.
Amade Oueremi, a native of Burkina Faso, fought alongside forces backing President Alassane Ouattara in the conflict, which erupted after former President Laurent Gbagbo refused to leave office despite losing the November 2010 election. At least 3,000 people died in five months of fighting, according to the United Nations.
Denis Badouon, vice mayor in the western town of Duekoue, said Oueremi was taken into custody Saturday morning in a village close to Mount Peko National Park, where the militia leader had been based since 1986, according to a U.N. report. He said multiple military sources had confirmed Oueremi's detention.
"I can confirm that he was arrested in the village of Bagohouo, not far from Mount Peko," Badououn said.
A military commander, who insisted on anonymity because he was not authorized to discuss the operation, said Oueremi had turned himself in after the military bolstered its presence in the region ? apparently in preparation for an operation to remove him from the national park.
It was not immediately clear whether Oueremi had been charged with a crime. In its 2011 report on the postelection conflict, Human Rights Watch said Oueremi was "among the main perpetrators" of the notorious March 2011 massacre in Duekoue that killed hundreds of Gbagbo supporters.
A May 2011 U.N. report says Oueremi began supporting anti-Gbagbo rebels as early as 2000, and that his men have been hording weapons and ammunition since then. The U.N. report notes that Oueremi is widely believed to possess "mystical powers." In photos taken during the crisis, his shirts are pulled tightly over a collection of charms and pendants seen bulging underneath, believed to give him protection from enemy fire.
Ouattara has tried to bridge lingering divisions in the two years since he assumed office, but this effort has been undermined by the lack of investigations of his own military supporters who are accused of committing grave human rights abuses during the conflict. Oueremi had become a symbol of this alleged impunity, traveling around the west in a conspicuous motorcade of dozens of cars and motorcycles even as officials openly acknowledged he was illegally occupying protected land.
Matt Wells, West Africa researcher for Human Rights Watch, called for an investigation into Oueremi's alleged crimes.
"Oueremi's capture should swiftly lead to a credible investigation and, evidence permitting, prosecution for his alleged role in some of the horrific crimes committed in Duekoue during the postelection crisis," Wells said. "By doing so, the Ivorian authorities would take a strong first step toward providing the impartial justice they have long promised, but yet to deliver on."
This Gillmor Gang was recorded live at betaday, the betaworks annual gathering in New York. The Gillmor Gang included John Borthwick, Robert Scoble, Douglas Rushkoff, Paul Davison, and Steve Gillmor. Enjoy.
![[ Back to EurekAlert! ]](https://lh3.googleusercontent.com/blogger_img_proxy/AEn0k_vC8-nM_06OVH4NXpLBy5jW0itTyGY9M2ex4dBkSgIS2DbBQQ_J07R5K1DIeI-MQDdzem4iFSSj9nbWsMaXnFJ5GpGD2rojD3A_zsY2HgQ=s0-d){kind=small}
Public release date: 21-May-2013
Share ] 
This Gillmor Gang was recorded live at betaday, the betaworks annual gathering in New York. The Gillmor Gang included John Borthwick, Robert Scoble, Douglas Rushkoff, Paul Davison, and Steve Gillmor. Enjoy.