Forms and structures of igneous rocks springerlink. It comes from deep in the earth where magma is formed. Metamorphic go 324a rocks and minerals at emporia state. Hydrothermal activity spatially associated with ultramafic rocks, usually serpentinites, has been observed at several localities proximal. Igneous rock igneous rock convergent plate boundaries. The minerals that make up igneous rocks crystallize at a range of different temperatures. This cheat sheet pack contains some practical advice on. The overall paper quality group grade is worth 90 points. Course notes on optical mineralogy can be found in both html and pdf formats on the tulane university geology dept. A magma consists mostly of liquid rock matter, but may. A magma consists mostly of liquid rock matter, but may contain crystals of various minerals, and may contain a gas phase that may be dissolved in the. Change is a result of pressure directed stress and heat solid state reaction no net change in chemistry ideally role of groundwater recrystallization of. Intrusive or plutonic igneous rocks wherein the magma crystallizes at depth in the earth. In the modern oceans, the mafic association is found in two specific settings.
Assimilation is that process of magmatic differentiation whereby ascending magmas evolve chemically by recruiting easily melted or dissolved components from the walls of their conduits. Under the agency of heat and magmatic fluids, ascending magmas pick up volatiles, silica, trace elements, and occassionally fragments of wall rock. F767 2014 5521dc23 2012168 isbn 9781107027541 hdbacra k. Hand specimen and thin section description of igneous rocks. Felsic tuffs, granite hard to tell from arkose when highly metamorphosed.
Mechanical deformation and chemical recrystallization are the two processes that affect rock during metamorphism. In practice, this means that the average dimension of the crystals is less than 1 millimeter. Classification and nomenclature of igneous rocks prof. This lecture is designed to give you a general overview of how igneous rocks are related to tectonic setting. A link within the document will lead you to a pdf file geared for printing this list.
Here, we look at this magmatism in terms of the volcanic rocks that appear to be related to subduction. The aim of the book is to help students to develop appropriate descriptive and inter. The minerals present in a rock and their relative proportions in the rock depend largely on the chemical composition of the magma. The iugs mineralogical based classification and nomenclature scheme for phaneritic and aphanitic igneous rocks. The book is divided into nine chapters and ancillary material.
This will lead us into discussions on magma, silicate minerals, and the construction of a useful illustration that may be used to both name an igneous rock and determine its mineral content. Many minerals occur in perfect crystalline form or recrystallized using the chemical constituents of the parent rock, which can be elongated in directions parallel to the. The prime example of this style of mineralization is the giant kidd creek deposit, where most mineralization occurred below the seafloor in permeable, fragmental felsic volcanic. This reader emphasizes how all igneous rocks are formed and explores how the formation is related to igneous rock classification. Igneous rocks are the oldest type of rock and is a volcanic rock. Dockery filled his childhood days exploring his jackson, mississippi, neighborhood with kids from his community.
Petrology of the crust, mantle and core, the convective cycle patterns in the. Igneous petrology cheat sheet 1 imperial college london. An introduction to igneous and metamorphic petrology, john winter, prentice hall. Igneous rocks associated with convergent plate boundaries have the greatest diversity. Nelson tulane university textures of igneous rocks introduction to igneous rocks an igneous rock is any crystalline or glassy rock that forms from cooling of a magma. In magma expressed in the form of bowens reaction series. Igneous petrology igneous rocks are assemblages of minerals predominantly rockforming minerals. We started looking at fossils and trying to identify our stuff.
Obsidian, for example, was magma hitting water and cooling super fast, so you can barely see the grains, its glassy. The igneous rocks are those which have solidified from a molten condition. Igneous rocks igneous rocks form by cooling and crystallization of molten rock molten material residing below earths surface is known as magma, whereas the same material at the surface is called lava. An impressive and complete set of igneous, sedimentary, and metamorphic petrology lecture notes, in both html and pdf. The modern study of igneous rocks utilizes a number of techniques, some of them developed in the fields of chemistry, physics, or other earth sciences. Vol 4 no 3 1966 tulane studies in geology and paleontology. An igneous rock is any crystalline or glassy rock that forms from cooling of a magma. To simplify the discussion we are severely reducing the number of.
Here we give very brief descriptions of most types of terrestrial and lunar igneous rocks, their regional distribution and classification, and examples of their geochemical trends and fingerprints. A wide variety of igneous rocks occur in the continental lithosphere, a reflection of its heterogeneous nature compared to oceanic lithosphere. Petrology and genesis of igneous rocks comprises of two parts the first part chapters 1 to 8 deals with constituent minerals, texture, thermodynamic principles, phase relations in natural rock systems and causes of diversity in a single petrographic province. General classification of igneous rocks tulane university. Original igneous, sedimentary, or metamorphic rocks recrystallize without melting, forming minerals and fabrics that are stable under certain pressuretemperature conditions. By comparison of their characters with those of certain igneous rocks intercalated in the geological column, it can be shown that the latter are the lavas of. Igneous rocks and processes revised on 102011 page 5 of 10 finegrained or aphanitic. Finegrained at low grade, coarser with increasing grade. Magmas and igneous rocks, discusses the composition of ig neous rocks and the interrelationships of elemental variation.
Papers published during the 19831986 period on the petrology and geochemistry of igneous rocks are discussed, with emphasis on tectonic environment. Minerals in abundances petrology of associated igneous rocks. This grade includes quality of petrographic analyses, sem calculations, grammar and spelling, layout, clarity, readability, critical evaluation of your data in comparison to data in the literature, proper captions and labels for your images, graphs, and figures, etc. Ndsu geosciences petrology 422622 petrology, petrography. These boundaries are destructive and consume the subducting oceanic lithosphere formed at the. Stratigraphic sequence of layering in the eastern lobe of the bushveld complex. The most obvious and unequivocal examples are the lavas which have been poured out from presentday volcanoes. Large igneous provinces lips these are massive outpourings of. An introduction to igneous rocks requires exploration of three core ideas. Igneous rocks are formed by crystallization from a liquid, or magma. Theres just a bewildering number of rocks to remember, minerals to be familiar with and textures to recognise. Mcdermott the basic terminology of igneous petrology. These lecture notes are part of a series of lectures available on the geology department website at tulane university. Because the continents are not subducted and are subject to uplift and erosion, older plutonic rocks are both preserved and accessible to study.
Igneous petrology cheat sheet 1 practical igneous petrology for dummies we can all be dummies when it comes to looking at igneous rocks. Felsic igneous rocks rhyolites, tuffs, granites if protolith 50% quartz then probably a sandstone or chert. This document last updated on 12feb2004 eens 212 petrology prof. Topics covered include criteria for the classification of igneous rocks, field identification of minerals present in hand sample, thin section examination and chemical analysis. Here we discuss a group of plutonic igneous rocks usually referred to. They include two types volcanic or extrusive igneous rocks form when the magma cools and crystallizes on the surface of the earth.
This is a medium grained intrusive igneous rock of basaltic composition. Metamorphism involves changes in mineral assemblage and rock texture and occurs in the solid state as a result of changes in temperature and pressure. The iugs systematics of igneous rocks article pdf available in journal of the geological society 1485. View notes igneous from eens 1110 at tulane university. Igneous rocks of the convergent margins tulane university. Each of these is introduced simplistically below, and then further explored in other pages of the site. Soon after geologists began doing chemical analyses of igneous rocks they. Databases of wholerock geochemical analyses for igneous rocks, thermobarometry, isotope geochronology, and plotting. Atlas of igneous rocks and their textures a companion volume to the atlas of rockforming minerals in thin section, this fullcolour handbook is designed to be used as a laboratory manual both by elementary students of earth sciences undertaking a study of igneous rocks in thin section under the microscope, and by more advanced students and teachers as a reference work. Teacher notes if your students have completed the plate tectonic units on volcanoes, they should be familiar with different volcanic environments. As a branch of geology, igneous petrology is closely related to volcanology, tectonophysics, and petrology in general.
Dockery iii at 5 years old picking up stray rocks and collecting them in a bucket could have predicted his career as an acclaimed geologist. Magma is a mixture of liquid rock, crystals, and gas. Tulane university petrology lecture notes collection. In this case, granite batholiths underlie the great composite volcanoes and consist of rocks ranging from basalt through andesite to dacite and rhyolite. Intrusiveextrusive lightdark small grainlarge grain the bigger the grains, the slower it cooled.
Igneous rock convergent plate boundaries britannica. Physical geology in our overview of the earth, we found out that earths internal heat combined with other mechanisms causes rocks to melt in the asthenosphere and lithosphere. Iugs subcommission on the systematics of igneous rocks. Metamorphic rocks are former igneous, sedimentary or metamorphic rocks that have changed their texture and composition. Igneous rocks page 1 of 14 eens 1110 physical geology tulane university prof. A wide variety of igneous rocks occur in the continental lithosphere, a reflection of its. Nelson magmas and igneous rocks magma and igneous rocks igneous rocks are formed by crystallization from a liquid, or magma.859 288 1185 896 69 806 1293 460 408 1310 300 355 1562 1310 29 723 1171 50 1249 1324 529 381 754 1317 316 1084 860 1063 309 760 935 735 331 964 51 202 432 213 1027 1068 1195 184 728 433 1475 1201 1274 600 1216