Antarctic Drilling Program


Date of this Version



Published in Terra Antartica, 2007, 14(3), 175-184. © Terra Antartica Publication 2007


Over 4300 natural and induced fractures were logged in AND-1B drill core. Induced fractures include steeply dipping, petal, petal-centreline, and core-edge induced fractures (n=421) which reach a maximum density of 5 fractures/metre. Subhorizontal induced extension fractures are also abundant. Natural fractures (n=1485) occur in Miocene to Pleistocene age strata and include faults, brecciated zones, veins and sedimentary intrusions. Kinematic indicators document dominant normal faulting, although reverse faults are also present. Vein types include slickenfiber veins along faults, opening-mode fibrous veins, pressure shadows on clast margins, and complex microvein webs within fault zones.