Please enable JavaScript.

Coggle requires JavaScript to display documents.

Project Yggdrasil, Welcome to Project: Yggdrasil, Here we store all…

- - - - Formation
        
        Magma/Lava cools
      - Geological Significance
        
        Mineral Deposits
        
        Tectonic reconstructions
        
        Radiometric dating
        
        Mantle composition
      - Geological setting
        
        Igneous rocks can be either intrusive (plutonic and hypabyssal) or extrusive (volcanic).
        
        Intrusive
        
        Country rock
        
        Batholiths
        
        Termed plutonic rocks
        
        Extrusive
        
        Volcanoes
        
        The volume of extrusive rock erupted annually by volcanoes varies with tectonic setting. Extrusive rock is produced in the following proportions:
        
        divergent boundary: 73%
        
        convergent boundary (subduction zone): 15%
        
        hotspot: 12%.
        
        Lava viscosity
        
        Felsic and Intermediate magma
        
        1 more item...
      - Classification
        
        Texture, Composition and Chemistry
        
        The classification of the many types of igneous rocks can provide important information about the conditions under which they formed. Two important variables used for the classification of igneous rocks are particle size, which largely depends on the cooling history, and the mineral composition of the rock. Feldspars, quartz or feldspathoids, olivines, pyroxenes, amphiboles, and micas are all important minerals in the formation of almost all igneous rocks, and they are basic to the classification of these rocks. All other minerals present are regarded as nonessential in almost all igneous rocks and are called accessory minerals. Types of igneous rocks with other essential minerals are very rare, but include carbonatites, which contain essential carbonates.
        
        In a simplified compositional classification, igneous rock types are categorized into felsic or mafic based on the abundance of silicate minerals in the Bowen's Series. Rocks dominated by quartz, plagioclase, alkali feldspar and muscovite are felsic. Mafic rocks are primarily composed of biotite, hornblende, pyroxene and olivine. Generally, felsic rocks are light colored and mafic rocks are darker colored.
        
        For textural classification, igneous rocks that have crystals large enough to be seen by the naked eye are called phaneritic; those with crystals too small to be seen are called aphanitic. Generally speaking, phaneritic implies an intrusive origin or plutonic, indicating slow cooling; aphanitic are extrusive or volcanic, indicating rapid cooling.
        
        An igneous rock with larger, clearly discernible crystals embedded in a finer-grained matrix is termed porphyry. Porphyritic texture develops when the larger crystals, called phenocrysts, grow to considerable size before the main mass of the magma crystallizes as finer-grained, uniform material called groundmass. Grain size in igneous rocks results from cooling time so porphyritic rocks are created when the magma has two distinct phases of cooling.
        
        Texture
        
        Textural criteria are less critical in classifying intrusive rocks where the majority of minerals will be visible to the naked eye or at least using a hand lens, magnifying glass or microscope. Plutonic rocks also tend to be less texturally varied and less prone to showing distinctive structural fabrics. Textural terms can be used to differentiate different intrusive phases of large plutons, for instance porphyritic margins to large intrusive bodies, porphyry stocks and subvolcanic dikes. Mineralogical classification is most often used to classify plutonic rocks. Chemical classifications are preferred to classify volcanic rocks.
        
        Mineralogical Classification
        
        The IUGS recommends classifying igneous rocks by their mineral composition whenever possible. This is straightforward for coarse-grained intrusive igneous rock, but may require examination of thin sections under a microscope for fine-grained volcanic rock, and may be impossible for glassy volcanic rock. The rock must then be classified chemically.
        
        3 more items...
        
        Chemical classification
        
        When it is impractical to classify a volcanic rock by mineralogy, the rock must be classified chemically.
        There are relatively few minerals that are important in the formation of common igneous rocks, because the magma from which the minerals crystallize is rich in only certain elements: silicon, oxygen, aluminium, sodium, potassium, calcium, iron, and magnesium. These are the elements that combine to form the silicate minerals, which account for over ninety percent of all igneous rocks. The chemistry of igneous rocks is expressed differently for major and minor elements and for trace elements. Contents of major and minor elements are conventionally expressed as weight percent oxides (e.g., 51% SiO2, and 1.50% TiO2). Abundances of trace elements are conventionally expressed as parts per million by weight (e.g., 420 ppm Ni, and 5.1 ppm Sm). The term "trace element" is typically used for elements present in most rocks at abundances less than 100 ppm or so, but some trace elements may be present in some rocks at abundances exceeding 1,000 ppm. The diversity of rock compositions has been defined by a huge mass of analytical data—over 230,000 rock analyses can be accessed on the web through a site sponsored by the U. S. National Science Foundation.
        
        The single most important component is silica, SiO2, whether occurring as quartz or combined with other oxides as feldspars or other minerals. Both intrusive and volcanic rocks are grouped chemically by total silica content into broad categories.
        
        4 more items...
        
        The percentage of alkali metal oxides (Na2O plus K2O) is second only to silica in its importance for chemically classifying volcanic rock. The silica and alkali metal oxide percentages are used to place volcanic rock on the TAS diagram, which is sufficient to immediately classify most volcanic rocks. Rocks in some fields, such as the trachyandesite field, are further classified by the ratio of potassium to sodium (so that potassic trachyandesites are latites and sodic trachyandesites are benmoreites). Some of the more mafic fields are further subdivided or defined by normative mineralogy, in which an idealized mineral composition is calculated for the rock based on its chemical composition. For example, basanite is distinguished from tephrite by having a high normative olivine content.
  - - - Igneous Petrology
      - Metamorphic Petrology
      - Sedimentary Petrology
      - Experimental Petrology
      - Petrology mainly focuses on the composition and texture of rocks
  - - - Noble Gases
      - Halogens
    - - Post-transition metals
      - Transition metals
      - Alkaline earth metals
      - Alkali metals
      - Lanthanoids
      - Actinoids
    - - Meitnerium (Mt)
- - - - Venus
        
        Zoozve
      - Mercury
      - Earth
        
        Moon
      - Mars
        
        Phobos
        
        Deimos
      - Theia
      - Other destroyed-in-the-progress rocky planets
      - Ice Giants
        
        Uranus
        
        Neptune
        
        Gas giants
        
        Saturn
        
        Jupiter
        
        Sun
        
        Protoplanetary Disk
        
        Asteroid Belt
        
        Kuiper belt
        
        Nemesis?
- - - - Cavemen
        
        Cave Drawings
      - Early Polytheism
        
        4000–3000 BC
        
        Hinduism
        
        2300–1500 BCE
        
        Buddhism
        
        idk
        
        Judaism
        
        1800 BC
        
        Christianity
        
        30 AC
        
        Islam
        
        610 AC
- - - - Deoxyribonucleic Acid
      - RNA