Sections

Ecological Land Types within LTA 153.

ELT 153a

Elevation Range
Minimum: 
717 m
Minimum in ft: 
2353 ft
Maximum: 
827 m
Maximum in ft: 
2714 ft
Median: 
780 m
Median in ft: 
2559 ft
Soil Summary: 
very deep,gravelly sandy loam over gravelly sandy loam and gravelly sandy clay loam; limy at or within a foot or so of the surface; no or modest development (clay accumulation); recent drainage channels are very deep; very gravelly fine sand over extremely gravelly sand, limy throughout with no soil development; Pima County soil survey map units 54 (Palos Verdes-Jaynes complex 2 to 8 percent slopes) and 5 (Arizo-Riverwash complex, 0 to 3 percent slopes) dominate. They comprise 68% and 31% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with early to latest Pleistocene alluvium (Qi1, Qi2, Qi3) and Holocene piedmont alluvium, undivided (Qy, Qy1) which comprise 71% and 29% of the unit, respectively
Landforms: 
undissected to coarsely dissected, weakly incised fan and pediment surfaces

ELT 153b

Elevation Range
Minimum: 
780 m
Minimum in ft: 
2559 ft
Maximum: 
941 m
Maximum in ft: 
3086 ft
Median: 
820 m
Median in ft: 
2690 ft
Soil Summary: 
very deep, very gravelly sandy loam to sandy loam surfaces with very gravelly sandy clay loam to clay subsoils, lime is absent or deeper in the soil profile, well developed (subsoil clay accumulation); Pima County soil survey map units 73 (Sasabe-Caralampi complex, 1 to 15 percent slopes), 18 (Combate gravelly loamy coarse sand, 2 to 8 percent slopes), and 9 (Caralampi extremely gravelly sandy loam, 5 to 15 percent slopes). They comprise 66%, 16% and 16% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with middle to latest Pleistocene alluvium (Qi2, Qi3); Boulder Conglomerate of Oro Valley, late Miocene to Quaternary (QTsb); Holocene piedmont alluvium, undivided (Qy,Qyr) and sandstone, siltstone and conglomerate, undivided (QTs) which comprise 45%, 20%,18%, and 17% of the unit, respectively
Landforms: 
moderately to finely dissected, weakly to moderately incised fan and pediment surfaces

ELT 153c

Elevation Range
Minimum: 
784 m
Minimum in ft: 
2572 ft
Maximum: 
865 m
Maximum in ft: 
2838 ft
Median: 
816 m
Median in ft: 
2677 ft
Soil Summary: 
very deep, gravelly sandy loam or very gravelly fine sandy loam over gravelly sandy loam and gravelly sandy clay loam or fine sandy loam or loam; limy at or within a foot or so of the surface; no or modest development (clay accumulation or movement); nearly complete coverage of the unit indicates Pima County soil survey map units 55 (Palos Verdes-Sahuarita complex 2 to 8 percent slopes) and 54 (Palos Verdes-Jaynes complex 2 to 8 percent slopes) dominate. They comprise 91% and 9% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with early to latest Pleistocene alluvium (Qi1, Qi2, Qi3) which comprises 93% of the unit
Landforms: 
undissected to coarsely dissected, weakly incised fan and pediment surfaces

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