A color image (237 Kb) showing the sort of fracture development that is typical of most parts of the sample. The orange-red luminescing grains, and the light-purplish red grains are quartz. The speckly orange grains are probably silicified volanic rock fragments. The dark blue grains could be either feldspar or carbonate, this has not yet been determined.

A grayscale image showing intensity of panchromatic CL (62 Kb). Close-up of a somewhat anastomosing macrofracture that cuts the sample. Fracture porosity is the labelled dark area. Left of center, euhedral quartz cement has filled the fracture. The cement appears to be predominantly post-kinematic, but one microfracture cuts the upper crystal near it's apex. A faint electronic interference pattern is present in the image, making a low-angle oblique diagonal sloping to the left.

Another grayscale image (113 Kb) showing the macrofracture that cuts the sample, subhorizontal just above the midpoint of the image. The elongate, streaky medium-gray area is fracture porosity. Several microfractures are present subparallel to the macrofracture. Several others are roughly perpendicular. Euhedral authigenic quartz cement grows into the

A close-up of the previous image (96 Kb) The concentricly-banded grain on the lower side of the fracture is probably a silicified volcanic (agate-like structure?). Note that the microfracture on the left side of the image that is perpendicular to the macrofracture cuts the euhedral quartz cement that is filling the fracture. The fractured grain on the top of the macrofracture is atypical of those seen along macrofractures. The grain crushing appears to have been synchronous with the growth of euhedral cement into the macrofracture. A faint electronic interference pattern is present in the image, making a low-angle oblique diagonal sloping to the left.

A color image (242 Kb) showing another portion of the macrofracture that cuts the sample. The fracture porosity is labelled and has a slightly bluish black in color. Note the pale blue grain that has been sliced into several pieces by repeated fracturing, and recementing (crack-seal texture).

A close-up of the previous image (183 Kb) showing the complex interplay of fracturing and cementation.

Grayscale image showing a spilt grain with complexly-zoned eudheral cement on either fracture face growing into the fracture porosity. (119 Kb) The quartz cement seems to be more abundant on fractured surfaces than on the exterior surfaces of grains that the fracture has anastomosed around.

Grayscale image of the macrofracture again (93 Kb). In this place there are more microfractures parallel to the macrofracture than elsewhere. Also the fracture filling cement shows a somewhat different pattern. A dark black unzoned cement present mostly on the upper edge, and in the large subsidiary fracture has been cut by a later fracture. Then euhedral, zoned, post-kinematic cement grows into the 2nd phase fracture porosity.

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