||Figure 5-9. A: Vertical stylolite (large red arrows) that crosscuts a horizontal stylolite (small red arrows).
B: High-magnification view of intersection of stylolites.
The morphology of the horizontal stylolite is very different on opposite sides of the vertical stylolite.
On the right, it has a typical stylolite morphology with columns perpendicular to the stylolite.
On the left, it has a more unusual morphology in which columns are at a low angle to the stylolite.
One interpretation of these relationships would be that a "normal" horizontal sylolite formed
first in response to vertical compression, and then the rock was subjected to horizonal
compression that formed the vertical stylolite and that move the lower left block farther right
than the upper left block. That relative movement along the left side of the horizontal stylolite
would account for it remobilization to produce columns nearly parallel to the stylolite itself.
Image was scanned directly from sample. Lewisburg, West Virginia, U.S.A.; Sample WV3-3.
Sample collected by L. Bruce Railsback and Lynn M. Andrews.