Breccia pipeとは 意味・読み方・使い方

A breccia pipe, also referred to as a chimney, is a mass of breccia, often in an irregular and cylindrical shape, that appears as an iron-stained knob, from several feet to several hundred feet in diameter. Breccia pipes may or may not be silicified. They usually consist of fragments of the host rock (the rock layer they are contained in) cemented together by silica. These formations are often used in mining, namely uranium. They are sensitive to oxidation, and due to their porous nature, may be oxidized to depths far below the ground surface. Breccia pipes that have never reached the Earth's surface are referred to as "blind".