Figure F2. Examples of induced structure types observed in Hole C0019E cores. White arrows = feature exemplified in image. A. Induced biscuit/disc fracture with characteristic arched bottom. All scales are in cm. B. Induced brecciation below white line, with characteristic angular, randomly oriented clasts exhibiting no slickenlines. C. Two low-angle triangular fracture sets in which the internal piece of rock bound by the fractures no longer remains. D. High-angle triangular fracture set in which internal piece of rock remains. E. Triangular fracture set in which the fracture with an apparent dip to the right of the photo has opened along a preexisting tectonic structure (denoted with dashed white line). F. Two approximately right angle fracture sets near bottom edge of an induced biscuit/disc. The fracture with an apparent steep dip to the right of the photo has opened along a preexisting tectonic structure (dashed white line). G. Radial fracture set (dashed white lines) propagating from an impact point likely at the location of the white arrow. H. Subvertical fractures in the pelagic clay at the base of Section 20R-2. I. Small saw-mark–parallel fractures that open in the same orientation as the horizontal saw-mark striations in the upper right portion of the photo. J. Induced fractures resulting from drilling mud injection. Drilling mud has a characteristic bright color that matches the fill in the fractures identified with white arrows. K. Open fracture crosscutting a zone of drilling mud injection. L. Zone of rubble, characteristically at the top of a core section with randomly oriented, mismatched fragments with no slickenlines.
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