Fault features Flashcards
What are slickensides?
surfaces are polished with linear grooves parallel to the direction of movement
how do slickensides form?
one surface of a rock moves over another under pressure
what is fault breccia?
large, angular fragment of rock formed during the faulting of hard, competent rocks
what are mylonites?
hard, crystalline, fine grained. metamorphic rock formed when shearing movement continues over long periods of time and individual crystals are fractures
where are mylonites found?
along major thrusts
how do mineral veins form?
hydrothermal fluids move up the fault planes and are deposited along the faults. The fluids fill the spaces and minerals crystallise along the fault planes
what are drag folds?
small subsidiary folds often found between competent and incompetent layers
where are drag folds found?
the sides of a major fold or adjacent to a fault
what are fault scarps?
they occur where ground rises steeply to the higher level of an upthrown block
how do fault controlled valleys form?
faults act as lines of weakness and are eroded to form fault controlled valleys
