The AAPG/Datapages Combined Publications Database
Journal of Sedimentary Research (SEPM)
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Journal of Sedimentary Research (SEPM); Year: 2021; Issue: No. 3. (March) DOI: 10.2110/jsr.2020.154
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Fig. 6. SEM images of dissolved calcite crystals for Series 5–8 representing different types of calcite reactants and degrees of fluid undersaturation with respect to calcite. Each horizontal row presents representative SEM images for one Series at 5%, 10%, and 30% dissolution. A) Series 5 (5% dissolution): crystals characterized by smooth edges and corners (white arrows) and etch pits (black arrows). B) Series 5 (10% dissolution): similar to Part A, crystals characterized by smooth edges and corners (white arrows) and etch pits (black arrows), but now some inter-crystal boundaries develop gulfs (black triangles) while other boundaries are characterized by sharp borders. Webs and strands of organic matter (OM with white arrows) are observed on and between crystals. C) Series 5 (30% dissolution): similar to Parts A and B, crystals characterized by smooth edges and corners (white arrows), inter-crystal gulfs (black triangles), and etch pits (black arrows), but crystals have a rougher appearance than in Parts A and B. D) Series 6 (5% dissolution): crystals characterized by sharp edges and corners, and sharp-sided, irregular pits (black arrows). Aggregates of equant and elongated nanocrystals are observed (gray arrows). E) Series 6 (10% dissolution): crystals characterized by irregular but parallel dissolution layers (white triangles), as well as a few dissolution pits (black arrows). Crystal edges and corners are slightly smoother than in Part E. F) Series 6 (30% dissolution): crystals characterized by smooth edges and corners (white arrows), and rough crystal surfaces. G) Series 7 (5% dissolution): crystals characterized by fine ledges (white triangles), and some smooth edges and corners, but they remain polyhedral. H) Series 7 (10% dissolution): crystals still characterized by polyhedral morphology, and wider and more visible ledges (white triangles) than in Part G. I) Series 7 (30% dissolution): crystals characterized by smoother and more curved edges and corners compared to Parts G and H, but they remain polyhedral. J) Series 8 (5% dissolution): crystals characterized by polyhedral morphology and distinct, deep, parallel ledges (white triangles). K) Series 8 (10% dissolution): similar to Part J, crystals characterized by polyhedral morphology, but the ledges (white triangles) become wider and more visible, and rare pits (black arrows) are observed. L) Series 8 (30% dissolution): similar to Parts J and K, crystals characterized by polyhedral morphology and ledges (white triangles), but the ledges are more separated and thus more visible. Crystal surfaces develop small, sharp-sided, irregular, and randomly oriented dissolution pits (black arrows).
Fig. 6. SEM images of dissolved calcite crystals for Series 5–8 representing different types of calcite reactants and degrees of fluid undersaturation with respect to calcite. Each horizontal row presents representative SEM images for one Series at 5%, 10%, and 30% dissolution. A) Series 5 (5% dissolution): crystals characterized by smooth edges and corners (white arrows) and etch pits (black arrows). B) Series 5 (10% dissolution): similar to Part A, crystals characterized by smooth edges and corners (white arrows) and etch pits (black arrows), but now some inter-crystal boundaries develop gulfs (black triangles) while other boundaries are characterized by sharp borders. Webs and strands of organic matter (OM with white arrows) are observed on and between crystals. C) Series 5 (30% dissolution): similar to Parts A and B, crystals characterized by smooth edges and corners (white arrows), inter-crystal gulfs (black triangles), and etch pits (black arrows), but crystals have a rougher appearance than in Parts A and B. D) Series 6 (5% dissolution): crystals characterized by sharp edges and corners, and sharp-sided, irregular pits (black arrows). Aggregates of equant and elongated nanocrystals are observed (gray arrows). E) Series 6 (10% dissolution): crystals characterized by irregular but parallel dissolution layers (white triangles), as well as a few dissolution pits (black arrows). Crystal edges and corners are slightly smoother than in Part E. F) Series 6 (30% dissolution): crystals characterized by smooth edges and corners (white arrows), and rough crystal surfaces. G) Series 7 (5% dissolution): crystals characterized by fine ledges (white triangles), and some smooth edges and corners, but they remain polyhedral. H) Series 7 (10% dissolution): crystals still characterized by polyhedral morphology, and wider and more visible ledges (white triangles) than in Part G. I) Series 7 (30% dissolution): crystals characterized by smoother and more curved edges and corners compared to Parts G and H, but they remain polyhedral. J) Series 8 (5% dissolution): crystals characterized by polyhedral morphology and distinct, deep, parallel ledges (white triangles). K) Series 8 (10% dissolution): similar to Part J, crystals characterized by polyhedral morphology, but the ledges (white triangles) become wider and more visible, and rare pits (black arrows) are observed. L) Series 8 (30% dissolution): similar to Parts J and K, crystals characterized by polyhedral morphology and ledges (white triangles), but the ledges are more separated and thus more visible. Crystal surfaces develop small, sharp-sided, irregular, and randomly oriented dissolution pits (black arrows).