contact aureole
Quick Summary
A contact aureole, also known as a contact zone, is a region of rock surrounding an igneous intrusion that has been altered by heat or magmatic solutions and gases. This process, called contact metamorphism, occurs when hot magma invades the Earth's crust and heats the adjacent rocks.123
The thickness of a contact aureole can range from centimeters around small intrusions like dikes to kilometers around large ones. The rocks within the aureole often lack distinct layering or foliation. These altered zones are typically found as the outer boundaries of contact aureoles, where the heat from the intrusion gradually diminishes, transitioning into the surrounding regional metamorphic grade.2
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