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Fig. 4. Micrographs (A, D, E) and SEM images (B, C, F, G, H) of select micromorphological features of protofragipan and fragipan horizons. (A) Glennie (E/B)x close-packing (close porphyric related distribution pattern and massive); (B) Feldhauser 2E/B closely packed fabric (sand grains are closely packed with relatively clean very fine sand, silt, and clay-sized particles; voids are primarily packing voids); (C) Glennie Ex, intergrain bridge (composed of silt [and some clay-sized particles] between sand grains; silt grains and clay platelets are oriented; bridge is  60 µm thick); (D) Munising (B/E)x void coating ([gray grainy] void coating; crescentic; limpid clay, impure clay; 50–125 µm; layered); (E) Glennie (E/B)x void infillings ([gray grainy] void infilling; dense incomplete; silty clay; 100–250 µm; compound); (F) Feldhauser 2E/B plan view of a void coating (smooth-surfaced void coating of surficially amorphous, clay-sized material; linear features in image may be root or fungal hyphae traces); (G) Feldhauser 2E/B plan view of degraded void coatings (remnants of void coating composed of silt grains and clay-sized particles; void groundmass predominantly consists of very fine sand and silt; void is channel-like in morphology; at a larger scale, surficially amorphous, clay-sized material appears to discontinuously coat silt grains and clay-sized particles of the degraded coating and groundmass; mechanism for coating degradation cannot be determined based solely on this image); (H) Glennie (E/B)x surficially amorphous material (mostly silt grains, and clay-sized particles or clay minerals [or both] with a discontinuous, bead-like coating of a surficially amorphous, clay-sized material <1 µm in diameter).
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