From the Soil Micromorphology Slide Collection

Description of slide: Densely packed basic material with mammilated vughs and channels. Locally, there is segregation of iron oxides as indicated by the red patches.

Data for the horizon
Horizon sampled: Bs2
Depth sampled: 108-123 cm
Physical and chemical data available: pH = 6.3, OC. = 0.1 %, free Fe203 = 8.3% Particle size distribution (deferrated): sand = 1 %, silt = 32%, clay = 67%
Clay mineralogy: Gibbsite dominant, goethite present
Macromorphological description of horizon: 2.5YR 4/6 clay; weak coarse and medium parting to fine and very fine angular blocky and granular structure
Micromorphological description of horizon: The plasma has few organic pigments and is uniformly yellowish red due to iron oxides. The plasmic fabric, also within denser patches, is inundulic to insepic. Skeleton grains are rare, mostly fine sand-size and silt-size. Few root remains are still present. Related distribution pattern is porphyroskelic (Stoops and Jongerius, 1975: c/f 2 µm open porphyric).

Soil Classification
U.S.: Clayey, gibbsitic, isohyperthermic Typic Acrudox
F.A.0.: Acri-Orthic Ferralsol

Elevation: 390 m above mean sea level
Physiographic position: Karst depression floored with bauxite deposits surrounded by limestone hills
Topography and hill slope position: Nearly level to gently undulating
Parent material: Bauxite overlying limestone of the White Limestone Formation
Soil climatic data and/or soil water balance: Annual rainfall approximately 2000 mm Vegetation: Citrus orchard with grass undergrowth in a tropical rainforest climate

Data for 35-mm slide
Light mode: Crossed polarized
Scale: Bar on slide = 200 µm

Andriesse W. and J. J. Scholten. 1982. Acri-Orthic Ferralsol (Haplic Acrorthox) Jamaica. ISM Soil Monolith Paper 6. International Soil Museum, Wageningen, The Netherlands.

Slide MS4. Soil Science Society of America, 1993. A Reference Slide Collection for Soil Micromorphology. SSSA, Madison, WI.