How To Use Magma In A Sentence

Its purpose is to gather sufficient information to answer questions about magma chambers in oceanic crust.
The established idea that granitoid magmas ascend through the continental crust as diapirs is being increasingly questioned by igneous and structural geologists.
Myles L. Miller, Scott S. Hughes, 2009, Mixing primitive and evolved olivine tholeiite magmas in the Eastern Snake River Plain, Idaho Scientific Articles on Yellowstone
But Darwin, happily insomnious with his vision of South America rising on swelling magma, thought this notion of collapsed lakes small thinking. Wired Top Stories
PhD opportunity in geophysical / geochemical process modeling of magma emplacement and fluid exsolution: Zurich, Switzerland Science jobs from ETH Zurich: job description Naturejobs - All Jobs

Melts form at the highest temperatures and lowest pressures resulting in large volumes of tholeiitic magma that form shield volcanoes such as Mauna Loa.
The magmatic fabric of a plutonic rock forms during a relatively short time interval, after ascent and before final crystallization of magma.
Subsequent melting of mica pyroxenite may produce potassic magmas as a result of orogenic or extensional, thermal or bark triggers.
The age of the Carrock microgranite provides further evidence that both calc-alkaline and tholeiitic magmas were available during Caradoc magmatism in the Lake District.
The remaining magma as lava domes and coulees was extruded with some associated subplinian or vulcanian explosive activity.
Scientists believe that diamonds ascend to the earth's surface in rare molten rock, or magma that originates at great depths.
The mechanism allows for great variation and complexity in magma chamber sedimentation.
Studies of layering in individual lava flows suggest that rising volatiles may effect mass transfer of complexed ions during differentiation in magma chambers.
Although there are no data showing the connection between the two magmatic systems at shallow crustal levels during the eruption, the petrochemical data point to a common parent magma derived from a unique deep source.
During Early Cretaceous times, there was a significant period of plutonism and crustal growth in the magmatic arc.
Many experiments suggest that ancient subduction-related metasomatism affected OIB mantle sources long before island magmatism.
Others, called volcanic earthquakes, are usually shallower and can be precursors to volcanic eruptions and intrusions of magma.
An aircraft will soon fly over the lava dome to test for the presence of carbon dioxide and sulfur dioxide, signs that magma might be building up.
igneous rock is rock formed by solidification from a molten state; especially from molten magma
Individual volcanoes of continental monogenetic volcanic fields are generally presumed to erupt single magma batches during brief eruptions.
In particular he studied magma flow beneath the Earth's surface to obtain a better understanding of volcanic eruptions when magma flows through fractures in the Earth's surface.
We envisage a convecting magma chamber of height H, cooled from above.
Of far less importance are occurrences in gneisses and amphibolites, in small plutons derived from syenitic and gabbroic magmas, and in certain contact-metamorphic rocks.
Second, in a process known as differentiation, crystals of olivine, clinopyroxene, and plagioclase began to crystallize from the magma, and being more dense than the magma, they settled to the bottom of the chamber.
The first is that, in addition to the basaltic magma associated with mid-ocean ridges, Iceland's volcanoes produce significant amounts of rhyolite, which is silica-rich and, more significantly, contains a lot more volatile substances. Ars Technica
Dissolved gases in the magma determine whether the eruption will be explosive or nonexplosive.
The early Permian rifting in the North Atlantic involved siliciclastic sedimentation in extensional basins and widespread extrusive and intrusive magmatic activity.
Star Saber and his elite guard defeat Magmatron's inner circle. The rebellion is crushed.
Teide is the highest mountain in Spain, an impressive stratovolcano in the center of the island of Tenerife, the largest of the Canary Islands, a chain formed like the Hawaiian Islands by the passing of the under-lying lithospheric plate across a magma plume. Teide National Park, Spain
In fluid magmas, such as those of basaltic composition, these gas bubbles can expand freely.
The classic mode of skarn formation involves high-temperature contact metamorphism wherein a silicate magma is intruded into a carbonate-rich sedimentary rock such as a limestone.
But there is a caveat-Karson noted that, historically, activity at Eyjafjallajökull has frequently preceded eruptions at the nearby Katla, which is a much bigger volcano and contains more rhyolitic magma. Ars Technica
Partial melting models, isotopic studies and the petrology of entrained ultramafic xenoliths suggest that many basanitic magmas are sourced in the asthenosphere.
Magmas erupted in continental volcanic arcs typically contain components from many sources in the crust, lithospheric mantle and asthenosphere.
Crystals of the mineral were then carried in suspension by the upward-moving magma and forced toward the center of the flowing slurry.
The occurrence of these heavy ores near the base of the norite naturally suggests that they were segregated by sinking to the bottom of the molten magma, but this conclusion implies certain physical conditions of the magma which have not yet been proved. The Economic Aspect of Geology
The selective removal of these minerals resulted in a change of the composition of the magma to one near that of the rock syenite.
Rising magma continues to build a lava dome in the crater of Mount St. Helens.
In other words, the magma is squeezed upwards as thin sheets through long, narrow fractures.
The resultant body of molten liquid, called magma, will solidify to produce the igneous rock, granite, but if it is still in liquid form as it approaches the surface, lava results. Centennial
Pockets of hot molten rock called magma collect beneath the surface of the Earth. CNN Transcript May 24, 2006
And then this tremor that everybody's talking about, it lasted for about 50 minutes, meaning that the lava or the magma, which is lava that's below the surface, is actually making its way up towards the surface. CNN Transcript Oct 3, 2004
The study authors propose another, more radical, explanation: The crustal rock they analyzed, called ferroan anorthosite, is not linked to magma dynamics at all.
In the process, their commitment to one another and to their vision for Magma grew more profound.
Fractionation of ferromagnesian phases such as olivine, pyroxene and magnetite must have taken place during magma emplacement, as is suggested by the low Co abundance.
The concepts of crystal settling and convection in magma chambers have a long history r2-6.
Volcanoes erupt not simply because magma is hot, but because hot, rising magma turns underground water to steam, which then expands explosively.
First, we assume that the magma degassing process is open, meaning that gas and bubbles are lost from the magma during degassing.
Vulcanites, such as basalt and fire opal, will be formed within erupted magma where cooling is rapid and only tiny crystals have the chance to form.
The land around Yellowstone regularly swells and subsides in response to the shifting levels of magma and volcanologists believe that one day the molten magma contained within the chamber will burst out - as it has done many times before.
It seems unlikely that the final magma pressure would have been the maximum value of magma pressure reached during the intrusive episode, and so flood basalts probably were erupted.
What they do know is that a ‘slow rise’ of magma is driving lava to the surface, which has created a new lava dome in the mountain's crater.
With the temprature cool, magma would be hardened into rock.
They suggest that liquid in the Martian crust was heated when the molten rock or magma rose to the surface.
Observations of graded bedding, trough structures and cross-layering suggested sedimentation from magmatic currents induced either by convection or by gravity currents.
Plutonites, also magmatic, form in conditions of extreme heat and pressure far deeper within the Earth; colourful translucent crystals such as aventurine, peridot and rose quartz are the result.
With the pultaceous deposit in the bladder there is incontinence of urine, which dribbles away continually and keeps the hair on the inner side of the thighs matted with soft magma. Special Report on Diseases of the Horse
From beneath the dome, the magma could combine with pressurized gases and steam to trigger an eruption, Pierson said.
Top graph shows the amount of magma fragmentation and resulting dispersal of tephra (ash and larger-sized particles) that typically accompanies different styles of eruption (for example, Hawaiian and Plinian). Volcanic ash hazards and ways to minimize them
Pastures of fresh magma flows known as pillow lavas and the rubble of frequent earthquakes line the floor of this stone trough.
Flumorph and SYP-48 all can restrain later development phase of Daphnia magma's embryo, such as larval curved or unextended shell spine, undeveloped antennae.
The provenance for the detrital material in the general region was to the east, in the continental arc, where magmatic and deformed lower Mesozoic rocks were exposed.
These migmatite complexes were mingled with the intrusive magmas that provided the heat sources for crustal melting.
Of fundamental importance here is the extent to which magma, which after being heated by the centrosphere rises and thus causes dominant processes, such as drifting-apart of continents and orogenesis, triggers climatic and sea level fluctuations as well.
Green Magma also contains the antioxidants alpha-carotene, beta-carotene, vitamin C, vitamin E succinate, superoxide dismutase SOD, catalase, and chlorophyll. Forever Young
These volcano and feeder systems have similarities to igneous centres, which also have cone-shaped edifices, calderas and downward tapering cones created during magma chamber collapse and ring-dyke intrusion.
Although no eruptions have been recorded at Yellowstone for 70,000 years, the hot springs, spectacular geysers, and bubbling mud pools provide testimony that hot magma still resides not far beneath the surface.
The question of why the plates move gets passed on to the geologists, who appeal to an upwelling of magma that pushes them apart.
The abundance of these elements in the parental magma leads to the formation of less-common minerals such as apatite, beryl, topaz, amblygonite, lepidolite, spodumene tantalite, columbite, monazite, zircon, and uraninite.
The mentioned above dating results imply that Mesozoic magmatism in the NCB chiefly happened in early Cretaceous.
Magma modelling showed that olivine nephelinite and basanite could form by different degrees of partial melting of the mantle source, with amphibole, garnet, olivine and clinopyroxene in the residuum.
The barley grass in Green Magma has been shown to contain a high level of antioxidants, including catalase and carotenoids, along with many other nutrients to help the body increase in overall antioxidant status, and therefore may be useful in supporting normal bone mass during menopause and beyond. Forever Young
Normally magma would fill the crack and the adjacent plates would inch away by just that amount.
The magmas that formed the batholith were generated in response to the subduction of the Farallon plate beneath the North American plate.
Layered intrusions commonly occur with mafic intrusions where the minerals (such as olivine, pyroxene, chromite, magnetite and plagioclase) have a wider range of specific gravity, and the magma viscosity was low.
Second, Dan Johnson is overseeing a microgravity experiment designed to measure minute changes in mass as magma moves and vesiculates.
The silicic rocks are interpreted as crustal melts resulting from intrusion of mafic magmas.
Slight changes in the slope of the volcano's flanks, as measured by a device called a tiltmeter, would suggest that gases were continuing to build up below as they bubbled out of the magma, causing the surface to bulge, or were dissipating. NYT > Home Page
A spectacular form of heat advection occurs when molten rock, or magma, erupts from a volcano.
This meant that the magma that fed the fissures of the second phase was almost completely de-gassed, hence its quiet emission.
During obduction, mantle-derived magmas most likely evolved to granitic compositions by assimilation of sediments and by fractional crystallization of amphibole, feldspar, titanite and allanite.
Instead it slowly froze in a magma chamber into a mush of coarse crystals.
Volcanicity and magma emplacement, largely in the form of large granite intrusions, characterize the volcanic arc.
The hot gases and magma melted the ice and snow that covered the mountain and the resulting mudflow continued throughout the night and the following day.
The Serra do Mar Mountain Chain is made up of ore-Cambrian granite porphyries and gneiss magma. Southeast Atlantic Forest Reserves, Brazil
In the cooler middle and upper crust, felsic magmatism and aqueous metasomatism are most important.
It further supportis the idea that the magnetic lineations represent the stretching direction of the deforming magma.
Steady rumblings have been recorded indicating the upward movement of magma.
These new vents remained phreatomagmatic until 25 July, when the activity changed for 5 days to Strombolian and effusive.
Such is the case in both basaltic and some silicic magmas. Jacob B. Lowenstern
In fluid magmas, such as those of basaltic composition, these gas bubbles can expand freely.
The magma here tends to be classified as felsic, with a much higher silicone content, which is more viscous in nature and allows for more gas to be trapped within. Thar She Blows « worlds in a grain of sand
Segregation vesicles are therefore distinguished from amygdales because they are infilled with chilled magma, whereas amygdales represent the infilling of vesicles from post-emplacement fluids.
A volcanic neck is simply the hardened magma in the ‘pipe’ or central channel of a volcano.
The effects of depth and degree of melting are well illustrated by terrestrial basaltic magma types, which can be divided into three broad groups: basalts, komatiites, and picrites.
Subordinate volumes of carbonatite and lamprophyre magmas are also present.
The hydrothermal activity may have been related to contemporary andesitic and/or granitic magmatism.
Well, the concern and the uncertainty that we're facing now is that we're not sure about the nature of the chemical composition of the magma that is involved in driving this thing.
The fault structure was veneered by lava which was produced by the peripheral magma reservoirs and flowed down the scarp and into the lower central caldera.
210Po has been shown to be highly volatile at magmatic temperatures and generally degasses almost completely during eruption. Coloradoan.com - Local News
As the magma in the intruding sill moves updip, the tensile stress on an intersecting fracture above the sill becomes greater, and the tensile strength of the sediments becomes less.
The origin of the vein-forming fluids - whether magmatic, meteoric, or connate - may also be determined from a study of the oxygen isotopes of the inclusions.
With the temprature cool, magma would be hardened into rock.
The sequential development of multiple summit calderas of shield volcanoes gives clues about how the spatial location of shallow magma chambers evolves with time and how the magma supply into these chambers evolves.
Sulphide infilled vesicles form numerous zones of disseminated magmatic sulphides within B-zones of thick komatiite lavas.
Several pools of syenitic magma were separated from the main body of the melt, each eventually being emplaced as quartz syenite, fayalite granite, and riebeckite granite.
Geological Survey crews also observed a shift in the crater floor and on part of the 1,000-foot lava dome that essentially serves as a plug for magma, he said.
East African volcanoes are famous for their carbonatites, and most of the eruptive magmas were rich in alkalis and natrocarbonatite.
In this paper, we discuss the tectonic settings and magmatic processes which allow these magmas to reach the surface.
Mesozoic Era complex plutonic masses from Shangyong area are composed of the plutones that are formed by Indosinian and Yanshanian cycle of structural magma and have different combination types.
SHRIMP U-Pb dating of recurrent Cryogenian and Late Cambrian-Early Ordovician alkalic magmatism in central Idaho: Implications for Rodinian rift tectonics EurekAlert! - Breaking News
When magma moves beneath a volcano, such as when the magma chamber fills prior to an eruption, there is swelling of the volcanic cone above.
The abundance of magmatic layering in this granite affords an unusual glimpse of early emplacement processes.
Instead, it will collect into huge underground reservoirs known as magma chambers. The Iceland Weather Report
Next in abundance, although rare in comparison to silicate rocks, are carbonate-based magmas and lavas known as carbonatites, which have little (less than 15 per cent by weight) or no silica content.
If the permeability of the rock is sufficiently high, and the density difference of the hot and cold groundwater is large enough, the groundwater body will start convecting in much the same way as happens above magmatic intrusions.
The shares have climbed 4. 7 % since the proposed Magma acquisition was announced.
In both cases, the sequence of events started with extensional basin magmatism and culminated in emplacement of plutons, passing through basin subsidence.
Magmas concentrate metals, and magma fluids traveling into the surrounding wall rock plant the seeds for mineral growth.
Whatever the source, an alkalic basaltic magma pooled in the potassium-poor rocks of the lower crust.
Until the rocks crystallized, uranium atoms could move freely through the molten magma from which they formed, and decayed uranium could be replenished.
Magmas erupted in continental volcanic arcs typically contain components from many sources in the crust, lithospheric mantle and asthenosphere.
As H2O builds up, density and viscosity decrease to a stage where the magma may again be sufficiently buoyant and mobile to rise further.
Thus, in magma chambers dense ferromagnesian minerals may sink to form cumulate rocks at the base of the chamber, whereas in partial melting a lower-density melt may percolate upwards.
Well, it's the largest grouping of magmatic features on Earth: huge geysers (Old Faithful can reach 190 feet), hot springs, steaming fumaroles, and mud pots - the sad remains of geysers that have lost their oomph.
The study work reveal that orogenic zone of west Qinling formed in Triassic Period should be a favorable area for finding Cu-Mo-Au deposit due to the thick crust and frequently magmatic activities.
This implies that individual primitive magmas are more likely to represent the composition of their individual mantle sources than more fractionated basalts.
As old oceanic crust was consumed in the trenches, new magma rose and erupted along the spreading ridges to form new crust.
Local hybridization between the mafic and felsic magmas is common.
The magmatic evolution is dominated by low-pressure crystal fractionation of olivine, Cr-spinel, plagioclase and clinopyroxene.
Most arc magmas have also undergone complex fractionation and contamination paths, which make attempts to quantify their petrogenesis difficult.
With the temprature cool, magma would be hardened into rock.
Prior to any volcanic eruption, magma wells up through the earth's crust via any weaknesses in the rock structure.
Their lineations, which are not influenced by the intrusion boundaries, faithfully reflect the stretching direction of the tectonic regime coeval with magma emplacement and cooling.
The inner ear's structure and contents is thought to permit the shark to determine and distinguish sounds and the geomagnetic fields of the earth's magma.
In both areas, the silicic magmatism is thought to have been a result of intrusion of mantle-derived mafic magmas into extending crust.
And in the case of magma it can foam and outgas very volatile compounds that can cause explosive eruptions and throw projectiles great distances.
Geochemical analyses of these clasts show that the eruption tapped two chemically distinct rhyolitic magmas.
The shares have climbed 4. 7 % since the proposed Magma acquisition was announced.
It appears that basic magmas across the Gardar Province were derived from a heterogeneous, enriched lithospheric mantle reservoir.
Various factors, including magma composition, control whether orthopyroxene or pigeonite occurs as the low-Ca pyroxene, but high temperatures yield orthopyroxene and low-pressure crystallization favours pigeonite.
I saw yellow-white explosions in my gut, and it seemed as if magma seeped through my bowels.
Igneous intrusions injected as a mobile magma may show sharp contacts with surrounding, or country, rocks.
Green Magma also contains the antioxidants alpha-carotene, beta-carotene, vitamin C, vitamin E succinate, superoxide dismutase SOD, catalase, and chlorophyll. Forever Young
It must be assumed that the crust in following downwards the shrinking subcrustal magma, develops immense compressive stresses in The Birth-Time of the World and Other Scientific Essays
The continuing uplift of the caldera rim can be explained by the restricted size of the magma's exit route.
As the magma approaches the surface it occasionally erupts and forms volcanoes.
This mineral is probably the product of incipient magmatic or deuteric oxidation that is apparently absent at Isparta.
Although their ages are correlative with the Parana Volcanic Province magmatism, the geochemistry, petrology and isotopic compositions of the Salta Rift magmas show different source regions and petrogenetic processes.
These can be related to rates of magma production versus differentiation by crystal fractionation within crustal magma chambers.
In some instances, stationary magmas solidify in situ.
This explains the occurence of gold deposits located near masses of granitic rock, which is solidified magma. Gold Rare | SciFi, Fantasy & Horror Collectibles
Their lower viscosity and greater lateral mobility explain why the mafic magmas were distributed over a much wider area than the felsic magmas.
Faulting and deformation may be concentrated at a caldera because the caldera structure and associated magmatic system form weak zones in the crust.
The earthquakes indicate releases of seismic energy and magma movement.
However, the intimate association of the ores with the primary minerals in the magma, together with their absence from higher parts of the norite and from the extraneous rocks far from the contact, indicate to other investigators that they were not brought in from outside in vagrant solutions which followed the intrusion of the main magma, but that they were segregated within the magma essentially in place. The Economic Aspect of Geology
Based on the position of the dikes, where was the source of the magma for the laccoliths located?
Eventually the central location within the volcano was again utilized for magma storage and a deep caldera was produced.
This, together with volatile exsolution, which creates buoyant magma, allows evolved magma to erupt.
The stone made its debut in the second issue of the 1985 Antarctic Meteorite Newsletter, classified as a diogenite, a subgroup of the achondrites, stony meteorites that are akin to terrestrial rocks formed from magma such as basalts. The Case for Mars
These can be related to rates of magma production versus differentiation by crystal fractionation within crustal magma chambers.
Dike geology, a subvertical sheet-like intrusion of magma or sediment Cheeseburger Gothic » So, Abe, got my ten bucks?
The deepest layer is gabbro, coarse-grained but chemically equivalent to basalt, which forms when magma cools and crystallizes slowly.
A large body of magma, capped by a hydrothermal system (a zone of pressurized steam and hot water), still exists beneath the caldera.
Our geochronology has identified major early Ordovician magmatism within the Slishwood Division.
The caldera has been the source of at least nine very large explosions over the last 300000 years, erupting a total of about 70 cubic kilometres (17 cu mi) of magma. WN.com - Photown News
In some instances, there is clear evidence for the accompanying emplacement of mantle-derived mafic magmas, providing a source for the anomalous heating.
If enough magma congealed around the exchangers it could degrade performance and cause damage.
Faults provide additional pathways, such as dykes, for magma transport and also may help to degas the magma during its ascent.
For example, volcanic eruptions range from (1) effusion of lava fountains and flows with very little ash erupted, typical of basaltic magma eruptions; to (2) extremely explosive eruptions that inject large quantities of ash high into the stratosphere, typical of rhyolite and dacite magmatic eruptions. Volcanic ash hazards and ways to minimize them
Xenoliths, which are pieces of wall rock, or xenocrysts, which are single mineral grains that originate from xenoliths, can commonly be recognized at outcrops of magmatic rocks.
In fluid magmas, such as those of basaltic composition, these gas bubbles can expand freely.
Geysers spout up where a column of underground water is heated to boiling by "magma, " or molten rock. Like a pan boiling over on your kitchen stove, this boiling pushes the water upward.
And by "hydrothermal vents," Amara is referring to ginormous magma chimneys that belch smoke from the bowels of the earth, forming lead-melting plumes of boiling black firewater at the ocean floor, which hordes of see-thru shrimp teem around, fearlessly basking in chemical-rich spew. Boing Boing: January 16, 2005 - January 22, 2005 Archives
A spectacular form of heat advection occurs when molten rock, or magma, erupts from a volcano.
Some geologists noted similarities between the lakes' steaming cracks and the fumaroles of volcano craters - and wondered if magma might be brewing there.
Today's oceans and continents are thus transitory features produced by incessant geotectonic processes that are energized by three sources of the earth's heat: energy conducted through the lithosphere from the underlying hot mantle, radiogenic decay of heat-producing crustal elements, and convective transport by magmas and fluids during orogenic events. Global material cycles
The region east of the gravity lineament has witnessed intensive magmatism and basin development since Mesozoic time.
Low glass viscosity and rapid welding of ignimbrite would be principally favoured by high-temperature emplacement, alkaline magmatic composition and incomplete degassing.
Rising magmas are the essential component for building the mineral deposits of the Andes.
The island contains a suite of rocks deposited in a forearc setting to the west of a magmatic arc, formed as the Pacific plate was subducted beneath Antarctica.
However, seismic interpretation within the saddle is rendered difficult by the presence of numerous magmatic intrusions in the Cretaceous section.
The geometry of the granite and the vertical displacement of the Dalradian can only be readily explained by the hypothesis that the granitic magma ascended diapirically prior to emplacement.
Magmas erupted in continental volcanic arcs typically contain components from many sources in the crust, lithospheric mantle and asthenosphere.
A further part deals with deposits associated with alkalic magmatism.
The revised age for the Jozini Formation rhyolites is also of significance for petrogenetic models proposed for the Karoo silicic magmatism.
Some of the largest mafic magmatic events may be related to catastrophic mantle overturn events or slab avalanches.
The mechanism allows for great variation and complexity in magma chamber sedimentation.
The abundance of magmatic layering in this granite affords an unusual glimpse of early emplacement processes.
During obduction, mantle-derived magmas most likely evolved to granitic compositions by assimilation of sediments and by fractional crystallization of amphibole, feldspar, titanite and allanite.
One aspect of Iceland's volcanoes of particular interest to geoscientists is that within the magmas being extruded there are small amounts of lightweight, light-colored volcanic materials known as felsic rock, which "has no reason whatsoever for being there - it's the kind of stuff found in continental crust, not ocean crust," Seaman says. Newswise: Latest News
The thickening of the crust beneath the Cordillera Blanca was by magmatic accretion since the Miocene.
Apply for PhD opportunity in geophysical / geochemical process modeling of magma emplacement and fluid exsolution Naturejobs - All Jobs
Some magmatic activity is concentrated along basement lineaments and other volcanism appears to be related to rifting in a similar way to that of major rift valleys.
basaltic magma is fluid
The mystery lies in the origin of the magma, which is molten rock that forms within the Earth. Newswise: Latest News
This area is a good example of the interplay of tectonic and magmatic processes.
The parental magma for pyroxenite xenoliths could be derived from the partial melting of the asthenosphere with continental crust material involvement and of the upper lithospheric mantle.
The tonalite is characterized by a strong fabric defined by aligned plagioclase, hornblende and biotite that is interpreted to be a magmatic state deformation fabric formed during emplacement.
Early minerals, such as the chromium-bearing mineral chromite, crystallize early and are denser than the surrounding magma.

How To Use Magma In A Sentence

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