Here's an exposure of a fault in limestone, with the acid bottle in leather holder for scale, the fault plane being entirely in shadow and facing or dipping to the left. This fault is way out in the hills, not one you can drive to without very good 4WD. (Poor, low-clearance 4WD might just get you high-centered trying to get there.)
It's an interesting fault, although I don't know much about the offset. It does have almost completely down-dip slicks, which can also be seen in the first photo. The apparent angle of the slickenlines in the second photo has something to do with the photo-taking procedure (or the photo person!).
The photo above is a long spliced-together image that will show more detail when enlarged (clicked on). The acid-bottle was sitting near the upper right side of the photo, where the dark shadow is the fault plane seen in the first and second photos, this time dipping straight towards us. You can follow the fault plane through the limestone from the right side of the photo to the left side, through the little green bush. The fault plane then kind of disappears in a mess of joints or fractures.
And this last photo shows a close-up of the area where the fault disappears or at least becomes more complicated. It may bend, or may be offset - I haven't quite figured that out! Sometimes in limestones, faults and fault planes get healed by post-faulting calcite recrystallization or surface weathering processes, and then they can become very hard to see.
Here's an exposure of a fault in limestone, with the acid bottle in leather holder for scale, the fault plane being entirely in shadow and facing or dipping to the left. This fault is way out in the hills, not one you can drive to without very good 4WD. (Poor, low-clearance 4WD might just get you high-centered trying to get there.)
It's an interesting fault, although I don't know much about the offset. It does have almost completely down-dip slicks, which can also be seen in the first photo. The apparent angle of the slickenlines in the second photo has something to do with the photo-taking procedure (or the photo person!).
The photo above is a long spliced-together image that will show more detail when enlarged (clicked on). The acid-bottle was sitting near the upper right side of the photo, where the dark shadow is the fault plane seen in the first and second photos, this time dipping straight towards us. You can follow the fault plane through the limestone from the right side of the photo to the left side, through the little green bush. The fault plane then kind of disappears in a mess of joints or fractures.
And this last photo shows a close-up of the area where the fault disappears or at least becomes more complicated. It may bend, or may be offset - I haven't quite figured that out! Sometimes in limestones, faults and fault planes get healed by post-faulting calcite recrystallization or surface weathering processes, and then they can become very hard to see.
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