What is special about kimberlite?
Kimberlites are the most important source of primary diamonds. Many kimberlite pipes also produce rich alluvial or eluvial diamond placer deposits.
What is a diatreme in geology?
Diatreme is a general term used to describe a volcanic vent or pipe that formed when magma was forced through flat-lying sedimentary rock.
How are kimberlites formed?
Kimberlite pipes are created as magma flows through deep fractures in the Earth. The magma inside the kimberlite pipes acts like an elevator, pushing the diamonds and other rocks and minerals through the mantle and crust in just a few hours.
Where do kimberlites form?
Kimberlite occurs in the Earth’s crust in vertical structures known as kimberlite pipes, as well as igneous dykes. Kimberlite also occurs as horizontal sills. Kimberlite pipes are the most important source of mined diamonds today. The consensus on kimberlites is that they are formed deep within the mantle.
What is a diatreme group of answer choices?
A diatreme, sometimes known as a maar-diatreme volcano, is a volcanic pipe formed by a gaseous explosion. Diatremes breach the surface and produce a steep, inverted cone shape.
Is ignimbrite an igneous?
Ignimbrite is a variety of hardened tuff. Ignimbrites are igneous rocks made up of crystal and rock fragments in a glass-shard groundmass, albeit the original texture of the groundmass might be obliterated due to high degrees of welding. The ash is composed of glass shards and crystal fragments.
Why are kimberlites extrusive?
Kimberlite, a form of peridotite is found in several locations in Riley County. Kimberlite is called intrusive igneous rocks because they were forced into other rocks below the surface of the Earth. It is a type of extrusive rock (forced out of extruded onto the Earth’s surface).
How are cratons and kimberlites related?
Generally speaking, kimberlites are found only in cratons, the oldest surviving areas of continental crust, which form the nuclei of continental landmasses and have remained virtually unchanged since their formation eons ago. This is why kimberlite pipes are the sites of most of the world’s diamond mines.
How do I identify a kimberlite rock?
kimberlite, also called blue ground, a dark-coloured, heavy, often altered and brecciated (fragmented), intrusive igneous rock that contains diamonds in its rock matrix. It has a porphyritic texture, with large, often rounded crystals (phenocrysts) surrounded by a fine-grained matrix (groundmass).
