INTRUSIVE ROCKS Meaning and
Definition
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Intrusive rocks are a type of igneous rock that solidifies below the Earth's surface through the process of cooling and crystallization from a molten state. As the name suggests, these rocks are intrusive in nature, meaning they intrude or penetrate the existing surrounding rocks. They are formed when magma, which is the molten rock material beneath the Earth's surface, rises and cools within the crust.
One defining characteristic of intrusive rocks is their coarse-grained texture. This occurs due to the slow cooling process that allows enough time for the mineral crystals to grow and develop. The individual mineral grains within intrusive rocks are visible to the naked eye, unlike the fine-grained texture of extrusive rocks that cool quickly on the Earth's surface.
Intrusive rocks form a variety of structures within the crust, such as dikes, sills, and batholiths. Dikes are tabular, sheet-like intrusions that cut across pre-existing rock layers, while sills lie parallel to the surrounding layers. Batholiths, on the other hand, are large masses of intrusive rocks that extend over several hundred square kilometers and can be exposed at the Earth's surface due to uplift and erosion.
In terms of composition, intrusive rocks can be classified into various types based on their mineral content. Some common examples include granite, composed mainly of quartz, feldspar, and mica, and gabbro, which consists largely of plagioclase feldspar and pyroxene. The composition of intrusive rocks provides insights into the geological processes and environments in which they were formed.
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In geol., applied to those igneous rocks which seem to have thrust themselves, while in a state of fusion, between the beds of the stratified formations.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
Common Misspellings for INTRUSIVE ROCKS
- intrusive rock3
- intrusive rockc
- intrusive rockq
- intrusive rockr
- inntrusiverocks
- i ntrusive rocks
- in trusive rocks
- int rusive rocks
- intr usive rocks
- intru sive rocks
- intrus ive rocks
- intrusi ve rocks
- intrusiv e rocks
- intrusive r ocks
- intrusive ro cks
- intrusive roc ks
- intrusive rock s
Etymology of INTRUSIVE ROCKS
The word "intrusive" comes from the Latin word "intrudere", which means "to thrust or insert". In geology, intrusive rocks are formed when molten magma solidifies below the Earth's surface, thus thrusting or inserting themselves into the existing rock formations. The term "intrusive rocks" emerged in the field of geology to describe these types of rock formations and their formation process.
