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increases as crystal size decreases), or of more soluble dolomite phases in the rocks, can result in the de-
velopment of vugs and intercrystalline pores. All such processes and resulting pore types can be repre-
Figure 3. Typical secondary dissolution pore types in carbonate rocks that are readily identifiable in cuttings and core samples.
A
interparticle pores in a grainstone (cuttings sample) and A' core showing interparticle porosity in a carbonate grainstone.
B
thin-section photomicrograph of intraparticle porosity (arrows) within a fusulinid and B' core showing intraparticle porosity
within a coral. C
Fenestral porosity in a tidal-flat dolomite. Tilted arrows point to planar (laminar) fenestral pores, and horizontal
arrows point to smaller "birdseye" pores. D
Cuttings samples with oomoldic pores (arrows) in an oolite grainstone. E Carbon-
ate grainstone with identifiable skeletal particles (circled) and larger vug (arrow) that formed from the initial dissolution of a parti-
cle and then further dissolution of the matrix around it (cuttings sample). F
Thin-section photomicrograph of interparticle poros-
ity in a carbonate sand wherein remnant cement (arrow) restricts pore throats and reduces permeability.
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