Archives par mot-clé : Geology

Scientists discover Earth’s youngest banded iron formation in western China

by University of Alberta, July 11, 2018 in ScienceDaily


Discovery provides evidence of iron-rich seawater much later than previously thought.

The banded iron formation, located in western China, has been conclusively dated as Cambrian in age. Approximately 527 million years old, this formation is young by comparison to the majority of discoveries to date. The deposition of banded iron formations, which began approximately 3.8 billion years ago, had long been thought to terminate before the beginning of the Cambrian Period at 540 million years ago.

The Early Cambrian is known for the rise of animals, so the level of oxygen in seawater should have been closer to near modern levels. “This is important as the availability of oxygen has long been thought to be a handbrake on the evolution of complex life, and one that should have been alleviated by the Early Cambrian,” says Leslie Robbins, a PhD candidate in Konhauser’s lab and a co-author on the paper.

New Holocene geological subdivisions. The Anthropocene nowhere to be found.

by Javier, July 9, 2018 in WUWT


The International Commission on Stratigraphy (ICS) has announced that the proposal by the International Subcommission on Quaternary Stratigraphy (ISQS) for the subdivision of the Holocene Series/Epoch has been ratified unanimously by the International Union of Geological Sciences (IUGS).

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nb:  ‘No Christiana, the geologists do not think the Anthropocene is a concept worthy of consideration, and you should be better informed.’

Oxford University Spreads Fake News

by Donna Laframboise, July 8, 2018 in BigPicNews


SPOTLIGHT: The most reputable publishers imaginable are misinforming the public about basic geology.

BIG PICTURE: Last September, a book titled The Paris Agreement on Climate Change: Analysis and Commentary appeared. Five people are listed as editors, four of whom are lawyers. Two teach at universities. Another two are United Nations legal officers.

These people aren’t lightweights. You’d expect them to be in possession of elemental facts.

Nevertheless, not one of these editors objected to a blatant falsehood in the Foreword to this book. It’s hard to find a more distinguished publisher than Oxford University Press, but none of its editorial team caught it, either. …

Anthropocene: The Media’s Fake Geological Epoch

by Donna Laframboise, July 2018, in BigPictureNews


SPOTLIGHT: Forget reporting facts. Journalists pick sides and spread false news.

BIG PICTURE: The Breakthrough Institute is known for its sensible approach to environmental questions. The current issue of its journal includes a tour de force titled “Welcome to the Narcisscene: Returning Humans to the Center of the Cosmos.”

Author Mark Sagoff spends 5,000 words discussing a topic that should appall anyone who worries about science being hijacked by politics. The short version is that there’s an international organization “responsible for naming and dating geologic periods, eras, and epochs.” Comprised of geologists, this organization has been under immense pressure to assert that planet Earth is no longer in the geological epoch known the Holocene.

For nearly 20 years, non-geologists such as Nobel-winning atmospheric scientist Paul Crutzen, have been insisting that a new epoch should be officially declared – one that acknowledges humanity’s influence on the planet. They think it should be called the Anthropocene. (In ancient Greek, anthrop means ‘human’.)

 

Rapid 3D analysis of rockfalls in Yosemite

by Geological Society of America, June 28, 2018 in ScienceDaily


On 27 and 28 September 2017, eight large rockfalls occurred from the southeast face of El Capitan. These rockfalls resulted in one fatality and two serious injuries, and spurred a complicated rescue and temporary closure of the main road exiting Yosemite Valley. In order to manage these challenging events, the National Park Service (NPS) had a critical, immediate need for quantitative information about the sequence of rockfalls and the potential for additional activity.

Using new “structure-from-motion” photogrammetry techniques in conjunction with baseline laser-scanning data, scientists from the NPS, the U.S. Geological Survey, and the University of Lausanne, Switzerland rapidly analyzed these rockfalls. By comparing 3-dimensional (3D) models of the cliff before, during, and after the rockfalls, the researchers were able to pinpoint the exact locations, dimensions, and volumes of the rockfalls, along with the spatial and temporal pattern of their progression up the cliff.

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What caused the mass extinction of Earth’s first animals?

by Arizona State University, June 27, 2018 in ScienceDaily


Scientists have argued for decades over what may have caused this mass extinction, during what is called the “Ediacaran-Cambrian transition.” Some think that a steep decline in dissolved oxygen in the ocean was responsible. Others hypothesize that these early animals were progressively replaced by newly evolved animals.

The precise cause has remained elusive, in part because so little is known about the chemistry of Earth’s oceans that long ago.

A research team, led by scientists from Arizona State University and funded by NASA and the National Science Foundation, is helping to unravel this mystery and understand why this extinction event happened, what it can tell us about our origins, and how the world as we know it came to be. The study, published in Science Advances, was led by ASU School of Earth and Space Exploration graduate student Feifei Zhang, under the direction of faculty member Ariel Anbar and staff scientist Stephen Romaniello. (…)

Geologists detail likely site of San Andreas Fault’s next major quake

by Utah State University, June 26, 2018 in ScienceDaily


The discovery of the Durmid Ladder reveals the southern tip of the San Andreas Fault changes fairly gradually into the ladder-like Brawley Seismic zone. The structure trends northwest, extending from the well-known main trace of the San Andreas Fault along the Salton Sea’s northeastern shore, to the newly identified East Shoreline Fault Zone on the San Andreas’ opposite edge.

“We now have critical evidence about the possible nucleation site of the next major earthquake on the San Andreas Fault,” says Jänecke, professor in USU’s Department of Geology. “That possible nucleation site was thought to be a small area near Bombay Beach, California, but our work suggests there may be an additional, longer ‘fuse’ south of the Durmid Ladder within the 37-mile-long Brawley Seismic zone.” …

Stacking Up Volcanoes

by Willis Eschenbach, June 25, 2018 in WUWT


As readers of my posts know, I’ve held for many years that there are a variety of emergent phenomena that regulate the earth’s temperature. See my posts The Thermostat Hypothesisand Emergent Climate Phenomena for an overview of my hypothesis.

One of the predictions derivable from my hypothesis is that the earth should be relatively insensitive to small changes in forcing. According to my hypothesis, if the total energy entering the system changes in such a manner that the global temperatures start to drop, inter alia the system responds through changes in the time and strength of the daily emergence of the tropical cumulus field and the associated thunderstorms. This allows more sunlight to enter the system and decreases the thunderstorm-caused surface heat losses, balancing out the energy lost elsewhere and maintaining the temperature.

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Why life on Earth first got big

by University of Cambridge, June 25, 2018 in ScienceDaily


Some of the earliest complex organisms on Earth — possibly some of the earliest animals to exist — got big not to compete for food, but to spread their offspring as far as possible.

The research, led by the University of Cambridge, found that the most successful organisms living in the oceans more than half a billion years ago were the ones that were able to ‘throw’ their offspring the farthest, thereby colonising their surroundings. The results are reported in the journal Nature Ecology and Evolution.

Prior to the Ediacaran period, between 635 and 541 million years ago, life forms were microscopic in size, but during the Ediacaran, large, complex organisms first appeared, some of which — such as a type of organism known as rangeomorphs — grew as tall as two metres.

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See also here

Study provides less gloom and doom about Antarctica

by Anthony Watts, June 22, 2018 in WUWT


Antarctic ice sheet is melting, but rising bedrock below could slow it down

An international team, led by DTU Space at the Technical University of Denmark with Colorado State University, has found that the bedrock below the remote West Antarctic Ice Sheet is rising much more rapidly than previously thought, in response to ongoing ice melt.

The study, “Observed rapid bedrock uplift in the Amundsen Sea Embayment promotes ice-sheet stability,” reveals new insights on the geology of the region and its interaction with the ice sheet and is published in the journal Science. The authors noted that the findings have important implications in understanding and predicting the stability of the ice sheet and Earth’s rising sea levels.

No. The Miocene is not an example of the “last time it was as warm as it’s going to get later this century”… Argh!

by David Middleton, June 19, 2018 in WUWT


From ARS Technica, one of the most incoherent things I’ve ever read…

The shocking thing is that Howard Lee has a degree in geology.  The fact that he makes his living as an “Earth Science writer” and not as a geologist might just be relevant.

Can the Miocene tell our future?  I’ll let Bubba’s mom answer that question:

 

HOW THE EARTH BECAME A HOTHOUSE BY H2O

by Wim Röst, June 15, 2018 in WUWT


Water, H2O, determines the ‘General Background Temperature’ for the Earth, resulting in Hothouse and Ice House Climate States. During geological periods the movement of continents changes the position of
continents, oceans and seas. Because of the different configurations, a dominant warm or a dominant cold deep-water production configuration ‘sets’ average temperatures for the deep oceans. Changing vertical oceanic circulation changes surface temperatures, especially in the higher latitudes. During a Hot House State, higher temperatures in the high latitudes result in a high water-vapor concentration that prevents a rapid loss of thermal energy by the Earth.

These three processes, plate tectonics (continental drift), vertical oceanic circulation variability and variations in atmospheric water vapor concentration and distribution, caused previous Hot House and Warm House Climate States. A change in the working of those mechanisms resulted in a transition from the previous Hot House Climate State to the very cold ‘Ice House State’ that we live in now. That change was set in motion by the changing configuration of continents, oceans and seas.

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Corals use epigenetic tricks to adapt to warmer and “more acidic” water

by JoNova, June 12, 2018 inJoNovaBlog


After half a billion million years of climate change, I’m shocked, shocked I tell you, that life on Earth (and specifically corals) have so many ways to cope with the climate changing. After all, it’s natural (if you are trained by Greenpeace) to assume that corals can only survive in a world with one constant stable temperature just like they never had.

One more tool in the coral-reef-workshop

Corals don’t just have a tool-box, they have a Home Depot Warehouse. h/t to GWPF

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Volcanic activity, declining ocean oxygen triggered mass extinction of ancient organisms

by Florida State University, June 11, 2018 in ScienceDaily


Global climate change, fueled by skyrocketing levels of atmospheric carbon dioxide, is siphoning oxygen from today’s oceans at an alarming pace — so fast that scientists aren’t entirely sure how the planet will respond.

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Millions of years ago, scientists discovered, powerful volcanoes pumped Earth’s atmosphere full of carbon dioxide, draining the oceans of oxygen and driving a mass extinction of marine organisms.