Sentences with phrase «fragmental volcanic materials»

Multiple episodes of volcanic material bubbling up from below may be needed to explain the features.

But researchers can not yet explain some of the features etched in that volcanic material: a spoke - like pattern of troughs and ridges emanating from the centre of the basin.

It emitted the enormous amount of 2,800 cubic kilometers of volcanic material with a dramatic global impact on climate and environment.

Scientists are now watching to see whether the volcano repeats the violent eruptions of 1963, when superheated gases and volcanic material raced down the mountain in a series of pyroclastic flows, killing more than 1000 people.

The raw volcanic material of central Idaho lies over the slopes in haphazard heaps.

Dr Simon Blockley and Dr Alison MacLeod, from the Department of Geography at Royal Holloway, analysed volcanic material that preserved the archaeological site in the village of Nor Geghi, in the Kotayk Province of Armenia.

«That's an awful lot of volcanic material in one place for such a little planet,» Zuber said.

For comparison: The Bárdabunga eruption blew out two cubic kilometers of volcanic material over the course of several months, nearly ten times more than the Eyjafjallajökull.

The scientists found that most of the volcanic material injected into the stratosphere settles out at a height of between 18 and 28 kilometres, with the greatest concentrations between 24 and 25 kilometres.

New Zealand scientists mapped the Havre volcano, a caldera nearly three miles (4.5 kilometers) across on the seafloor northeast of the North Island of New Zealand, using shipboard sonar instruments in 2002 and again immediately after the eruption in 2012, revealing the presence of new volcanic material on the seafloor.

Brought to Earth's surface in eruptions of deep volcanic material, these rocks hold clues as to what is going on deep beneath Earth's surface.

This process leads to the eruption of large volcanic material (flood basalts) at the Earth's surface.

Recent inspection of the sulfate records from the European project for ice coring in Antarctica's dronning maud land (EDML) ice core reveals sulfate peaks that have been correlated to presumed YTT sulfate peaks in the North Greenland ice core project (NGRIP) and GISP2 ice cores; however, once again no volcanic material has been identified (18).

An exceptional sulfate spike in the Greenland Ice Sheet Project Two (GISP2) ice core record, of 6 y duration, has been correlated to the YTT (16) despite an absence of volcanic material.

Lead author of the study Dr Tom Gernon, Lecturer in Earth Science at the University of Southampton, said: «When volcanic material is deposited in the oceans it undergoes very rapid and profound chemical alteration that impacts the biogeochemistry of the oceans.

The widespread volcanic material suggests the presence of water - formed clay which can reduce friction — an effect seen on Earth at volcanoes in Hawaii.

But an ideal landing site, Moriarty says, might be a spot that has both mantle and volcanic material, because those volcanics are interesting in their own right.

At the bulleye's center is a region of what appears to be deposits of volcanic material, a sign that the center of the basin may have been covered by a volcanic flow sometime soon after the SPA impact.

Lava rock may quickly lower pH and some volcanic material is sharp enough to cut fish that rub against it.

From a sea kayak the island looks like a layer cake of multi-colored volcanic material that depicts its interesting geological history.

Heavy rainfall on the fragmental volcanic materials triggered flows of mud and boulders to additional flanks of the mountain.

The beach contains a large amount of olivine crystals, the same that originate from volcanic materials.

Geologically the area is very complex, being a combination of marine sedimentary rocks of the Cretaceous - Tertiary period and intrusive volcanic material, including lavas and granites.

This played an important role as the injection of volcanic material was so large in the Toba eruption that some chemical processes saturated, leading to a longer presence of sulfur - containing particles in the stratosphere.

These hazards have the potential to cause coastal erosion, landslides, mudslides, epidemics, and the movement and spread of toxic substances and volcanic material.

Not exact matches

Other sources of salts include the solid and gaseous materials that escaped from the Earth's crust through volcanic vents or that originated in the atmosphere.

Zipkin contrasts working with specular hematite — a heavy, glittery rock that's deep purple - red and has a high iron content — with material much lighter in both color and iron content from Kenya's volcanic Rift Valley: «They're both ochre, but elementally and chemically they are radically different.»

In that sense, the researchers say, the moon is unique: Its craters are constantly erased by the solar system's most relentless volcanic activity — 25 times more frequent than that seen on Earth — which adds an estimated 1 centimeter of fresh material to Io's surface each year.

The chemistry of obsidian varies from volcano to volcano, and the chemical «fingerprints» allow researchers to match an obsidian artefact to the volcanic origin of its raw material.

Obsidian, naturally occurring volcanic glass, is smooth, hard, and far sharper than a surgical scalpel when fractured, making it a highly desirable raw material for crafting stone tools for almost all of human history.

The material, they believe, was recycled as older volcanic rocks forming the roofs of magma chambers collapsed and remelted during eruptions, only to be reejected in the next volcanic outburst.

Yellowish inclusions are pumice, dark stony fragments are lava, gray areas consist of other volcanic crystalline materials, and white spots are lime.

Pore spaces that shelter subsurface microbes areconstricted to the vanishing point in metamorphic rocks buried over eons byfurther sedimentation, volcanic eruptions, or massive folding of Earth's crust.And dense crystalline material formed by melting — basic igneous rock — offerslittle housing or dining.

Slow - moving seismic waves, hotter than surrounding material, interact with plumes rising from the mantle to affect the formation of hotspot volcanic islands.

Volcanic eruptions in Iceland in 2010 and 2011 are also important sources of material, they say.

Their claim was especially surprising because EETA 79001, like all Martian meteorites, is a volcanic rock, in which you wouldn't expect to find sedimentary material.

The pink areas are new deposits of volcanic ash; the orange plug is older material.

A group of former and current Arizona State University researchers say chemical differences found between rocks samples at volcanic hotspots around the world can be explained by a model of mantle dynamics that involves plumes, upwellings of abnormally hot rock within the Earth's mantle, that originate in the lower mantle and physically interact with chemically distinct piles of material.

Unlike the ash that forms from burning wood or other combustible materials, volcanic ash is hard and abrasive, rather than soft and fluffy.

In particular, eruptions such the Timanfaya's in Lanzarote ─ one of the strongest in the country due its duration until 1736 and the amount of thrown material ─ and Tambora's ─ one of the biggest volcanic episodes, which led to a «year without summer» in 1816 ─ released big amounts of iron that altered the chemical composition of the annual Pyrenean tree rings.

However, they add, testing has affected both the limestone and the underlying volcanic rock in a way which is likely to increase «the longer - term potential for leakage of radioactive material».

Lepre said a layer of volcanic ash below the tool site set a «floor» on the site's age: It matched ash elsewhere that had been dated to about 3.3 million years ago, based on the ratio of argon isotopes in the material.

When basalt — a volcanic rock that makes up roughly 70 percent of the earth's surface — is exposed to carbon dioxide and water, a chemical reaction occurs, converting the gas to a chalk - like solid material.

Recent studies have revealed volatile material embedded in lunar volcanic glass collected by Apollo astronauts.

In the spring 2017 issue, meet the people who work round the clock at Argonne's giant synchrotron, using X-rays to tease out the secrets of everything from volcanic glass to batteries to bacterial machinery — as well as engineers who travel the world to make reactors safer, physicists who collect model ships, and scientists inventing materials for the next technology breakthroughs.

«If they are volcanic, then the summit depression would likely have formed via collapse as material is erupted from underneath.

Supervolcano isn't a true scientific term, Benson explained, but generally refers to a volcanic eruption that produces at least 1,000 cubic kilometers of material.

Yet another surprising discovery would be cryovolcanism — volcanic eruptions of gaseous material such as water, ammonia or methane — on Pluto.

Moriarty and Pieters found several such craters in the volcanic patch where the pyroxene material has been re-excavated.

Making moai — the haunting statues of Easter Island — involved carving a range of volcanic and sea - made materials, and then moving them into place.