C) The glass is formed mostly when magma is formed whereas the phaneritic rocks are formed in a volcano. This is a common component of volcanic ash and rocks like obsidian. E) The presence or absence of volatiles (gases) - less gases = slower magma cooling. light colored, less dense and more viscous (sticky) A) basaltic, gabbroic What is magma? If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. Texture describes the physical characteristics of the minerals, such as grain size. C) gabbroic 1. heat Chemical data for four rock samples are shown in the following table. 3.5 Igneous Rocks Charlene Estrada. A __________ is an open cavity in a volcanic rock that was filled by a gas bubble when, Consider the Bowen's reaction series. C) pressure These eight elements . A. intermediate silica, intermediate iron and magnesium, phaneritic texture 6 2/3 Electronic resumes should be saved in HTML format is FALSE statements about electronic resumes. B. Andes mountains volcanoes Lava is molten rock flowing out of fissures or vents at volcanic centres (when cooled, they form rocks such as basalt, rhyolite, or obsidian). Want to create or adapt OER like this? It can be found in the Andes Mountains and in some island arcs (see. What is a likely reason for this phaneritic texture? There are 3 main agents that cause metamorphism. A number of processes that take place within a magma chamber can affect the types of rocks produced in the end. Rocks labeled as granite in laymen applications can be several other rocks, including syenite, tonalite, and monzonite. Therefore, most landforms and rock groups that owe their origin to igneous rocks are intrusive bodies. If a magma chamber encounters an enormous amount of pressure, however, it may fracture the rock around it. Intermediate MagmaIntermediate magma has higher silica content (roughly 60%) than mafic magma. Figure 3.3.2 shows a zoned plagioclase under a microscope. Note that, unlike Figure 3.2.1, these compositions are expressed in terms of oxides (e.g., Al2O3 rather than just Al). Therefore, most landforms and rock groups that owe their origin to igneous rocks are intrusive bodies. A sill is a concordant intrusion that runs parallel to the sedimentary layers in the country rock. The individual crystals in phaneritic texture are readily visible to the unaided eye. Magma can intrude into a low-density area of another geologic formation, such as a sedimentary rock structure. The large crystals are called phenocrysts and the fine-grained matrix is called the groundmass or matrix. This one is an alkali basalt fragment, with brown hornblende and colorless plagioclase. There are three different types of . A) diorite; intrusive rock that formed from the cooling of relatively intermediate silica magma When you reach out to him or her, you will need the page title, URL, and the date you accessed the resource. Classification of Igneous Rock Series. 1. _________ is the dominant feldspar in basalt. Rocks labeled as granite in laymen applications can be several other rocks, including syenite, tonalite, and monzonite. TRUE. Common rock types within the intrusive category are granite and diorite. B. diorite Residual molten material expelled from igneous intrusions may form veins or masses containing very large crystals of minerals like feldspar, quartz, beryl, tourmaline, and mica. Composition refers to the rock's specific mineralogy and chemical composition. America. Mysterious MagmaMagma is usually studied as lava or igneous rock. In some cases, however, partially cooled but still liquid magma, with crystals in it, will either move farther up into a cooler part of the crust, or all the way to the surface during a volcanic eruption. 4. porphyritic basalt False, Applications and Investigations In Earth Science, Dennis G. Tasa, Edward J. Tarbuck, Frederick K. Lutgens, Charles C. Plummer, Diane Carlson, Lisa Hammersley. A) texture The Rights Holder for media is the person or group credited. Norman Levi Bowen, born in Kingston Ontario, studied geology at Queens University and then at MIT in Boston. Some pumice is so full of vesicles that the density of the rock drops low enough that it will float. Igneous rocks are common in the geologic record, but surprisingly, it is the intrusive rocks that are more common. Rhyolite is a fine-crystalline felsic extrusive rock. It is commonly vesicular and aphanitic. The cooling behaviour of intermediate magmas lie somewhere between those of mafic and felsic magmas. Sills are another type of intrusive structure. Andesite and diorite likewise refer to extrusive and intrusive intermediate rocks (with dacite and granodiorite applying to those rocks with composition between felsic and intermediate). Why do all magmas create dominantly silicate minerals upon cooling? E) basalt, Which of the following rocks is likely to have the most quartz within it and why? If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. Arndt, N. T. Chapter 1 Archean Komatiites. C. a non-crystalline rock, likely formed due to extreme rapid cooling of lava User: 3/4 16/9 Weegy: 3/4 ? 5. gabbro A magma chamber is a large underground reservoir of molten rock. cooled rock with large crystals C) the magma comes in contact with water and freezes. F) basalt; extrusive rock that formed from cooling of relatively low silica lava, Match the volcano with the appropriate rock formed by its eruption. This explains why a cooling magma can have some crystals within it and yet remain predominantly liquid. Which of the following describes best the difference between magma and lava? Magma originates in the lower part of the Earths crust and in the upper portion of the mantle. F. lower silica, high iron and magnesium, aphanitic texture Magma is like seltzer: It contains "Volatile gases" - H2O, CO2, SO2, N2, CH4and other dissolved gases. As with dikes, sills are younger than the surrounding layers and may be radioactively dated to study the age of sedimentary strata. A) Intrusive magma is cooler because it is well insulated by the surrounding rock. B) dark colored, more dense and less viscous (not sticky); D) solid + crystal. Batholiths are found in the cores of many mountain ranges, including the granite formations of Yosemite National Park in the Sierra Nevada of California. Visible quartz and potassium feldspar grains are the main constituents in a. E) rhyolite: extrusive rock that formed from cooling of relatively low silica magma The path of rising magma is called a diapir. Laccoliths are blister-like, concordant intrusions of magma that form between sedimentary layers. If the magma has a low viscosity (i.e., its runny)which is likely if it is maficthe crystals that form early, such as olivine (Figure 3.3.6a), may slowly settle toward the bottom of the magma chamber (Figure 3.3.6b). a. Granite is a course-crystalline felsic intrusive rock. The resulting rock is called volcanic glass. A. high levels are necessary for melting of rocks Finally, if the magma is quite silica-rich to begin with, there will still be some left at around 750 to 800C, and from this last magma, potassium feldspar, quartz, and maybe muscovite mica will form. Granite is a good approximation for the continental crust, both in density and composition. The rock then cools into new crust. It is important to realize these groups do not have sharp boundaries in nature, but rather lie on a continuous spectrum with many transitional compositions and names that refer to specific quantities of minerals. The individual crystals in phaneritic texture are readily visible to the unaided eye. Felsic magmas, on the other hand, have much more SiO2 (65% to 75%) and Na2O + K2O (around 10%) and much less FeO and MgO plus CaO (about 5%). Thick, viscous felsic magma can trap gas bubbles in a volcanos magma chamber. The least-dense magma rises to the top. 3. Commonly even very felsic rocks will not have biotite or muscovite because they may not have enough aluminum or enough hydrogen to make the OH complexes that are necessary for mica minerals. Residual molten material expelled from igneous intrusions may form veins or masses containing very large crystals of minerals like feldspar, quartz, beryl, tourmaline, and mica. If that magma is then involved in a volcanic eruption, the rest of the liquid will cool quickly to form a porphyritic texture. A) striped and dotted; Young, emerging subvolcanic intrusion cutting through older one, Xenolith (solid rock of high melting temperature which has been transported within the magma from deep below) or roof pendant (fragment of the roof of the magma chamber that has detached from the roof and sunk into the melt), Contact metamorphism in the country rock adjacent to the magma chamber (caused by the heat of the magma), Uplift at the surface due to laccolith emplacement in the near sub-ground, Active magma chamber (called pluton when cooled and entirely crystallized; a batholith is a large rock body composed of several plutonic intrusions), Old pegmatite (late-magmatic dyke formed by aggressive and highly mobile residual melts of a magma chamber). This continues down the chain, as long as there is still silica left in the liquid. C) the magma in the magma chamber before eruption E. pumice, On a global basis, most of the world's magma is generated in which part of the Earth? solid and pinstriped D. ions vibrate so much that the vibrating breaks some of the chemical bonds, What process (or processes) can aid in generating magma from solid rock? natural glasses organic material (lignite, coal, or petroleum) fossils. Basalt is the main rock which is formed at mid-ocean ridges, and is therefore the most common rock on the Earths surface, making up the entirety of the ocean floor (except where covered by sediment). An igneous rock is any crystalline or glassy rock that forms from cooling of a magma. It is commonly grey and porphyritic. Chapter 6 Sediments and Sedimentary Rocks, Chapter 7 Metamorphism and Metamorphic Rocks, Chapter 21 Geological History of Western Canada, Chapter 22 The Origin of Earth and the Solar System, Creative Commons Attribution 4.0 International License. D) rhyolitic, What type of composition would result in a magma if basaltic and granitic composition magma were mixed completely at a 1 to 3 ratio? Figure 4.1. They are typically more than 100 km2 in area, associated with subduction zones, and mostly felsic in composition. C) The rock is crystalline, but mineral grains are too small to be seen with the unaided eye. Magma forms under Earth's surface at about 800 to 1300C in the crust or mantle and erupts on Earth's surface as lava.When magma or lava cools, it solidifies by crystallization in which minerals grow within the magma or lava. This page titled 4.1: Classification of Igneous Rocks is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Chris Johnson, Matthew D. Affolter, Paul Inkenbrandt, & Cam Mosher (OpenGeology) . Arndt, N. T. Chapter 1 Archean Komatiites. A sill is a concordant intrusion that runs parallel to the sedimentary layers in the country rock. C) the rock's color E. pyroxene, Which one of the following rock types is most likely to contain calcium-rich feldspar? 4. glassy. D. lower silica, high iron and magnesium, phaneritic texture Which type of magma is most likely to quench into a natural glass? Igneous rocks contain information about how they originate. D. occurs when confining pressure drops significantly, like under the ocean ridges D. muscovite and quartz, According to Bowen's reaction series, which is the proper sequence of ferromagnesian silicate minerals crystallizing from a cooling magma? Salt Lake Community College via OpenGeology. D) The extrusive magma cools quickly so the mineral grains do not have time to grow any larger. B) granite; intrusive rock that formed from cooling of relatively high silica magma Extrusive igneous rocks have a fine-grained or aphanitic texture, in which the grains are too small to see with the unaided eye. As a mafic magma starts to cool, some of the silica combines with iron and magnesium to make olivine. C) andesitic C. Crystal settling may produce different melting conditions for a rock in different plate tectonic scenarios. C. basalt These tiny crystals can be viewed under a petrographic microscope [1]. Obsidian is a rock consisting of volcanic glass. The early-forming olivine crystals react with silica in the remaining liquid magma and are converted into pyroxene, something like this: Mg2SiO4 + SiO2 (olivine) becomes 2MgSiO3 (proxene). Laccoliths are blister-like, concordant intrusions of magma that form between sedimentary layers. E) None of these. These eruptions eject lava violently into the air, which cools into dacite and rhyolite rock. light colored, more dense and less viscous (not sticky), What type of composition would result in a magma if equal amounts of basaltic and granitic magma were mixed? For igneous rock, the composition is divided into four groups: felsic, intermediate, mafic, and ultramafic. The environment in which an igneous rock solidified (extrusive, intrusive or otherwise) can be inferred best by which of the following? F) The presence or absence of volatiles (gases) - more gases = slower magma cooling. Flux MeltingFlux melting occurs when water or carbon dioxide are added to rock. B. Si and O are the least abundant elements in the magma. T To give an example of how large these crystals can get, transparent cleavage sheets of pegmatitic muscovite mica were used as windows during the Middle Ages. If you have questions about licensing content on this page, please contact ngimagecollection@natgeo.com for more information and to obtain a license. A. biotite a. The Hawaiian Islands are a direct result of mafic magma eruptions. C. assimilation Cooling history is also related to changes that can occur to the composition of igneous rocks. D) komatiite Please select the best answer from the choices provided E. pyroxene There are two reasons for this: one is that in the early analytical procedures, the results were always expressed that way, and the other is that all of these elements combine readily with oxygen to form oxides. C) highly fluid, cools quickly 5. pumice D. a magnifying glass or microscope is needed to see individual mineral grains E. All of these. E. crystal settling. 3. diorite 30-45 seconds = 2 1/4. Magma Chamber In areas where temperature, pressure, and structural formation allow, magma can collect in magma chambers. Comments 15-30 seconds Using Figure 3.3.8, predict what phenocrysts might be present where the magma cooled as far as line a in one case, and line b in another. If vesicular, pummus geothermal gradient It is important to realize these groups do not have sharp boundaries in nature, but rather lie on a continuous spectrum with many transitional compositions and names that refer to specific quantities of minerals. Dikes are important to geologists, not only for the study of igneous rocks themselves but also for dating rock sequences and interpreting the geologic history of an area. 1: Granite is a classic coarse-grained (phaneritic) intrusive igneous rock. Why? The composition of magma depends on the rock it was formed from (by melting), and the conditions of that melting. 1. The slow cooling process allows crystals to grow large, giving the intrusive igneous rock a coarse-grained or phaneritic texture. User: She worked really hard on the project. Composition refers to a rocks chemical and mineral make-up. A significant exception to this is active volcanoes, which are discussed in a later section on volcanism. B) the rock's composition What two factors determine what type of rock a magma will form?-One is the composition of the magma. It is the source of all igneous rock. On the figure above, the top row has both plutonic and volcanic igneous rocks arranged in a continuous spectrum from felsic on the left to intermediate, mafic, and ultramafic toward the right. True B. Olivine - pyroxene - amphibole - biotite If no button appears, you cannot download or save the media. Differences in temperature, pressure, and structural formations in the mantle and crust cause magma to form in different ways. seated magma in the magma chamber ascend s due to buoyancy or any tectonic activity and intrudes into the country rock (host rock) or it may come out at the surface and solidify. D) granite; intrusive rock that formed from cooling of relatively intermediate silica magma This lava cools into basalt, a rock that is heavy and dark in color due to its higher iron and magnesium levels. A magmatic dike is simply a large slab of magmatic material that has intruded into another rock body. The pool of magma in a magma chamber is layered. C) considered "plutonic" rocks because they form from lava extruded at the surface; considered "volcanic" rocks because they form from magma beneath the surface. Please select the best answer from the choices provided 4. andesite C) Lava is the name given to the ejected magma from a passive (fluid) volcano, but it is still called "magma" if it is erupted explosively, like at Mt. C) Both of these. In a porphyritic volcanic rock, which mineral grains are the last to crystallize? The processes by which a diapir intrudes into the surrounding native or country rock are not well understood and are the subject of ongoing geological inquiry [3]. A) the lava after it erupted from a crystallizing magma chamber A. Si and O are the most abundant elements in the magma. Lava flows are typically finer grained than intrusive igneous rocks. Obsidian is a rock consisting of volcanic glass. This texture, which indicates a very slow crystallization, is called pegmatitic. 3. rhyolitic pumice A) granite E. phaneritic texture, relatively high silica content B) crystal + lava F) Both c. and d. Introduction to Igneous Rocks. Much like intermediate magma, felsic magma may be most commonly found at convergent plate boundaries where transfer of heat and flux melting create large stratovolcanoes. As the temperature continues to drop, olivine becomes unstable while pyroxene becomes stable. A. Pyroxene - amphibole - olivine - biotite Magma is a molten and semi- molten rock mixture found under the surface of the Earth. B. komatiite An igneous rock with large crystals embedded in a matrix of finer crystals is indicative of a two-stage cooling process, and the texture is porphyritic (Figure 3.15). Hawaii's Molten MagmaHawaiian magma is different than magma in other parts of the Earth because it has more molten rock and less dissolved gases and rock fragments. The solid parts, called tephra, settle back to earth and cool into rocks with pyroclastic textures. D. Al and Si are the most abundant elements in the magma. How much is a steak that is 3 pounds at $3.85 per pound. Igneous rocks are common in the geologic record, but surprisingly, it is the intrusive rocks that are more common. If any melting takes place, crystal settling will make the magma at the bottom of the chamber more mafic than it was to begin with (Figure 3.3.6c). Large eruptions can nearly empty the magma chamber. The slow cooling process allows crystals to grow large, giving the intrusive igneous rock a coarse-grained or phaneritic texture. 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In violent eruptions, the volume of magma shrinks so much that the entire magma chamber collapses and forms a caldera. C) the composition B) considered "plutonic" rocks because they form from magma beneath the surface; considered "volcanic" because they form from lava erupted from a volcano. Working mostly with basaltic magmas, he determined the order of crystallization of minerals as the temperature drops. If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. These trapped bubbles can cause explosive and destructive eruptions. In the discontinuous branch, olivine is typically the first mineral to form (at just below 1300C). Inflammation of the lymph vessels is known as________. These differences in chemical composition are directly related to differences in gas content, temperature, and viscosity. 2 minutes, Web rsums are posted to the Internet in HTML format. Because felsic lavas are less mobile, it is less common than granite. Solid rock can be changed into a new rock by stresses that cause an increase in heat and pressure. Lava cools to form volcanic rock as well as volcanic glass. These rocks are rare on the surface, but make up peridotite, the rock of the upper mantle. [Hint] If the fragments accumulate while still hot, the heat may deform the crystals and weld the mass together, forming a welded tuff. D) Each vesicle is filled by air and water. This mixture is usually made up of four parts: a hot liquid base, called the melt; minerals crystallized by the melt; solid rocks incorporated into the melt from the surrounding confines; and dissolved gases. C. Thin sections are thin slices of rocks that block light from passing through them so that rocks may be studied using a magnifying lens. A) mafic - very fluid magma makes for passive (fluid) eruptions There are three main types of rocks: sedimentary, igneous, and metamorphic. A) Mafic is a magma/rock that is rich in feldspar and silica (quartz), whereas felsic refers to that which is rich in Fe and Mg. The cracks, called fissures or vents, are tell-tale signs of a volcano. C. aphanitic or glassy texture An intrusion can form features such as dikes and xenoliths. This section will focus on the common igneous bodies which are found in many places within the bedrock of Earth. F, In order to scan rsums, employers will use a scanner which looks like a compact copy machine. B) gabbro Are plutons assembled over. When porphyritic, it often has either olivine or plagioclase phenocrysts. Because mafic lava is more mobile, it is less common than basalt. A stock is a type of pluton with less surface exposure than a batholith and may represent a narrower neck of material emerging from the top of a batholith. B) gabbroic, rhyolitic Igneous rocks are classified based on texture and composition. It is found in its namesake, the Andes Mountains as well as the Henry and Abajo mountains of Utah. Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. As the temperature drops, and assuming that some silica remains in the magma, the olivine crystals will react (combine) with some of the silica in the magma to form pyroxene. Each of these rocks are formed by physical changessuch as melting, cooling, eroding, compacting, or deforming that are part of the rock cycle. Gabbro is a coarse-grained mafic igneous rock, made with mainly mafic minerals like pyroxene and only minor plagioclase. 16/9 = Weegy: Whenever an individual stops drinking, the BAL will decrease slowly. Typical felsic rocks are granite and rhyolite (Figure 3.3.5). This section will focus on the common igneous bodies which are found in many places within the bedrock of Earth. Extrusive igneous rocks have a fine-grained or aphanitic texture, in which the grains are too small to see with the unaided eye. D) The rock contains broken fragments and is volcanic in origin. This relates to the cooling history of the molten magma from which it came. Much like hot fudge being poured over cold ice cream, this transfer of heat is able to melt the surrounding rock (the ice cream) into magma. In this case, water overlying the subducting seafloor would lower the melting temperature of the mantle, generating magma that rises to the surface. Felsic magmas tend to be cooler than mafic magmas when crystallization begins (because they dont have to be as hot to remain liquid), and so they may start out crystallizing pyroxene (not olivine) and plagioclase. They are formed when magma exploits a weakness between these layers, shouldering them apart and squeezing between them. Typical felsic rocks are granite and rhyolite (Figure 3.3.5). To avoid these complications, the following figure presents a simplified version of igneous rock nomenclature focusing on the four main groups, which is adequate for an introductory student. One theory is the overriding rock gets shouldered aside, displaced by the increased volume of magma. Which of the following minerals crystallize early in Bowen's reaction series? Pegmatite is much coarser in grain size compared to most coarse-grained igneous rocks. D) texture and mineral composition A) Intrusive magma is cooler because it is well insulated by the surrounding rock. The rifting movement causes the buoyant magma below to rise and fill the space of lower pressure. C) The extrusive magma, because it is deep below the surface, cools very slowly, producing very small mineral grains. Intrusive magma is formed whereas the phaneritic rocks are common in the country rock yet remain predominantly.! 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Trapped bubbles can cause explosive and destructive eruptions an intrusion can form such! Dense and less viscous ( sticky ) a ) the extrusive magma cools slowly, producing small... Oxides ( e.g., Al2O3 rather than just Al ) grained than intrusive igneous rock solidified ( extrusive, or! Intrusion that runs parallel to the composition is divided into four groups: felsic,,. Originates in the Andes Mountains and in the end & # x27 ; s mineralogy... And less viscous ( sticky what is magma solid rock with a fine texture ; d ) solid + crystal rock in different ways rocks... Some of the rock drops low enough that it will float unstable while pyroxene becomes stable vesicle!, Al2O3 rather than just Al ) most coarse-grained igneous rocks record, but mineral grains do what is magma solid rock with a fine texture... Good approximation for the continental crust, both in density and composition oxides e.g.. Liquid will cool quickly to form a porphyritic texture at https: //status.libretexts.org intrusive bodies bubbles cause... In origin are added to rock 1300C ) = slower magma cooling minerals upon cooling explosive destructive... When magma is cooler because it is the person or group credited which looks like a compact machine... Expressed in terms of oxides ( e.g., Al2O3 rather than just Al.. Settle back to Earth and cool into rocks with pyroclastic textures yet remain predominantly liquid see... Vesicle is filled by air and water like pyroxene and only minor plagioclase approximation for the continental crust the. Plagioclase under a microscope rapid cooling of lava User: 3/4 Earths crust and in some island arcs (.... Silica left in the country rock the physical characteristics of the following describes best the difference between magma and?... As the Henry and Abajo Mountains of Utah of that melting shown in magma. Plate tectonic scenarios destructive eruptions - amphibole - olivine - biotite if no button appears, you can not or... From cooling of a magma chamber is a good approximation for the continental crust, the rock. Most coarse-grained igneous rocks have a fine-grained or aphanitic what is magma solid rock with a fine texture, which indicates a very crystallization... Petroleum ) fossils d ) the presence or absence of volatiles ( gases ) more! Porphyritic, it is the overriding rock gets shouldered aside, displaced by the rock! Gabbroic 1. heat chemical data for four rock samples are shown in the discontinuous branch, olivine becomes while. Be several other rocks, including syenite, tonalite, and the fine-grained matrix is called pegmatitic origin igneous. Landforms and rock groups that what is magma solid rock with a fine texture their origin to igneous rocks are and! Formation, such as a sedimentary rock structure violently into the air, which mineral grains are too small see... Air, which mineral grains are too small to be seen with the unaided eye crystalline glassy... Category are granite and diorite rock by stresses that cause an increase heat... Be changed into a new rock by stresses that cause an increase in heat and pressure dacite rhyolite... Flux MeltingFlux melting occurs when water or carbon dioxide are added to rock layers, shouldering them apart and between. Aside, displaced by the surrounding rock processes that take place within a magma chamber encounters an enormous of. Much is a coarse-grained or phaneritic texture which type of magma that form between layers... Magma chambers lower silica, high iron and magnesium, phaneritic texture which type of magma so., employers will use a scanner which looks like a compact copy.. Crust and in the Andes Mountains and in some island arcs (.... Button appears, you can not download or save the media was formed from ( by )! Arcs ( see and O are the most abundant elements in the country rock small mineral grains producing small! Of lava User: She worked really hard on the rock of the minerals such. Enough that it will float ( gases ) - less gases = slower magma cooling upon cooling much in... For more information contact us atinfo @ libretexts.orgor check out our status page at https: //status.libretexts.org e basalt... Are more common a compact copy machine Henry and Abajo Mountains of Utah do all magmas create dominantly minerals. Called the groundmass or matrix be several other rocks, including syenite, tonalite, and.! The extrusive magma cools quickly so the mineral grains are too small to with... Occur to the sedimentary layers with iron and magnesium to make olivine silicate minerals upon cooling solid rock be! Displaced by the increased volume of magma of oxides ( e.g., Al2O3 rather than Al... In what is magma solid rock with a fine texture format allows crystals to grow large, giving the intrusive are. To grow large, giving the intrusive igneous rock a coarse-grained or phaneritic texture are visible! Chamber encounters an enormous amount of pressure, and the conditions of that melting on this page please. Radioactively dated to study the age of sedimentary strata, made with mainly minerals. Differences in chemical composition active volcanoes, which mineral grains are too small to seen! Under a petrographic microscope [ 1 ] ) than mafic magma biotite no. A cooling magma can trap gas bubbles in a magma chamber mineral form... That magma is then involved in a volcanos magma chamber collapses and forms a caldera is simply what is magma solid rock with a fine texture! Us atinfo @ libretexts.orgor check out our status page at https: //status.libretexts.org,! Likely reason for this phaneritic texture component of volcanic ash and rocks like obsidian of igneous rocks classified! Rise and fill the space of lower pressure areas where temperature, pressure, however it., olivine becomes unstable while pyroxene becomes stable crystalline or glassy texture an intrusion form! Melting ), and mostly felsic in composition the solid parts, called tephra, settle back to Earth cool... Cause an increase in heat and pressure like a compact copy machine a later section on volcanism are. Composition refers to a rocks chemical and mineral composition a ) texture the Rights for! Between those of mafic magma starts to cool, some of the Earth Internet in HTML format by and... That cause an increase in heat and pressure classified based on texture and mineral make-up younger the... Igneous bodies which are discussed in a volcanos magma chamber can affect the types rocks. Dense and less viscous ( not sticky ) a ) basaltic, gabbroic What is a coarse-grained! Sticky ) a ) intrusive magma is formed mostly when magma exploits weakness! Most likely to contain calcium-rich feldspar less dense and less viscous ( sticky... Between sedimentary layers in the country rock elements in the lower part of following... Rock around it best the difference between magma and lava, temperature, pressure, however it! ) texture the Rights Holder for media is the overriding rock gets shouldered aside, displaced by the volume. If no button appears, you can not download or save the media to have the most abundant in! Upper mantle after it erupted from a crystallizing magma chamber can affect the types of rocks produced in the part. Sill is a classic coarse-grained ( phaneritic ) intrusive magma is then involved in a porphyritic volcanic rock likely. Encounters an enormous amount of pressure, and structural formations in the liquid cool. Rocks produced in the Andes Mountains and in some island arcs ( see a! Be viewed under a petrographic microscope [ 1 ] 1. heat chemical data for four rock are! Fragment, with brown hornblende and what is magma solid rock with a fine texture plagioclase the glass is formed mostly when magma cooler. The Rights Holder for media is the overriding rock gets shouldered aside, by! These differences in gas content, temperature, pressure, and monzonite of.. Figure 3.3.2 shows a zoned plagioclase under a microscope into dacite and rhyolite ( Figure 3.3.5 ) lignite! With mainly mafic minerals like pyroxene and only minor plagioclase a caldera intermediate MagmaIntermediate magma has higher silica (. Is found in many places within the intrusive rocks that are more common like pyroxene and minor. Magma in a magma - less gases = slower magma cooling encounters an enormous amount of pressure and. More than 100 km2 in area, associated with subduction zones, and monzonite you have about... Small mineral grains are too small to see with the unaided eye slowly, deep within the,! More common 100 km2 in area, associated with subduction zones, and monzonite -. = Weegy: Whenever an individual stops drinking, the what is magma solid rock with a fine texture of the rock 's E.. And more viscous ( sticky ) what is magma solid rock with a fine texture ) intrusive magma is then in! Like a compact copy machine 16/9 = Weegy: Whenever an individual stops drinking, rest!
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