Figure 1-4. A: Sutured contact (red arrow) between two quartz grains in a quartz-cemented quartzose sandstone. Unmodified grain margins (black arrows) would extend to overlap (red dashed lines) at the contact. B: same area in cross-polarized light. At the center of the intergranular space. cements syntaxial on the two pressure dissolved grains meet with cement syntaxial to a third are a common point (black arrow). The difference in clarity between the grains and their cements further demonstrates that the suture (red arrow) is at an intergranular contact and not a compromise boundary between cements.

      Photomicrographs were taken in plane and cross-polarized light; field of view of each is 0.27 mm wide. Lower Silurian Red Mountain Formation, Interstate 75 Ringgold Gap roadcut, Georgia, U.S.A; Sample S-3-105; thin section S-3-105. Sample collected by L. Bruce Railsback.

   
  Image
   
   
  Back to the Table of Contents of the Atlas of Pressure Dissolution Features.