vs FeO (Fig 5), which is distinct from A-14 basalts. Diabase is an example of an intrusive rock. All about Diabase rocks. H2S gas can be dissolved in water to produce hydrosulfuric acid, which will cause corrosion when it comes into contact with metal. Basalt and its intrusive equivalents (dolerite and gabbro) are by far the most abundant igneous rocks on the surface of the Earth and other rocky planets and satellites in the solar system. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). Geologists consider traprock to be any dark-colored, fine-grained, nongranitic, hypabyssal or extrusive igneous rock, such as basalt, peridotite, diabase or fine-grained gabbro. Ca(OH)2 makes the water alkaline and further reduces the water resistance of the slag cotton. By definition, basalt is a fine-grained basic igneous rock composed of calcic plagioclase and augite, with or without olivine. NNL meteorites are a suite of LAP meteorites with similar compositions and are believed to be sourced from the same location. gabbro: coarse grained intrusve mafic rock Fine grained rocks, and basalts in our case, can also form in hypabyssal settings (underground, for example dykes) if conditions are favourable for very quick nucleation. It is important to note that there are many, many intermediate steps between these main divisions. Sedimentary Rocks: This typically happens when volcanoes erupt. diabase: fine grained intrusive cools below ground) mafic rock. This is a name given to those varieties of what would otherwise be diorite and gabbro which are too fine-grained in character to enable one to tell whether the dark-colored mineral which they contain is hornblende or pyroxene without the use of a microscope. Basalt is an example of an extrusive rock. Diabase or Dolerite Diabase or dolerite is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. The Zr/Hf of NWA 12839 is well above chondritic and plots above the other A12 basalts, which is characteristic of high-Ti basalts . Basalt is clearly the most common volcanic rock on Earth and basaltic rocks (including gabbro, diabase and their metamorphosed equivalents) are the most common rocks in the crust 2.Basalt is also common on the Moon and other rocky planets of the Solar System. coarse grain Granite: Diorite: Gabbro: Peridotite: Glassy: Obsidian : Frothy: Pumice : Scoria . Extrusive rocks are formed when magma comes to Earth’s surface and cools rapidly. basalt: fine grained extrusive (cools above ground) mafic rock. Diabase, also called Dolerite, fine- to medium-grained, dark gray to black intrusive igneous rock.It is extremely hard and tough and is commonly quarried for crushed stone, under the name of trap. The rocks diabase and basalt are discussed more specifically later on in this activity. Assuming that we are talking about rocks of this specific composition, then every extrusive rock is a basalt but not every intrusive rock is a gabbro (or diabase). Intermediate : Dacite: Diabase : Phaneritic. Basalt: Conditions needed to produce ultramafic flows do not exist in nature at this time. The basalt rock wool board uses basalt or diabase as a raw material, there is no sulfur source, so no corrosion will occur. Basalt is a major rock type that occurs in virtually every tectonic setting. Diabase is most easily confused with basalt, but the ubiquity and size of clinopyrox- ene phenocrysts and in some cases the texture and size of plagioclase crystals serve as diagnostic markers.