Multimedia Gallery - Carbonate nodule coated and partly impregnated with Mn oxide

From the Soil Micromorphology Slide Collection

Description of slide: Carbonate nodule (1.3 mm long) coated and partly impregnated with Mn oxide. The nodule has a porphyric related distribution pattern and crystic plasmic fabric. Neomangans coat the nodule and Mn oxide partly impregnates it. The horizon in which the nodule occurs has a porphyroskelic related distribution pattern. Its plasmic fabric is mo-skelsepic.

Data for the horizon
Horizon sampled: Bwk1
Depth sampled: 23-45 cm
Physical and chemical data available: 15% sand, 27.5% silt, 57.5% clay; also see reference
Data for thin section
Preparation of sample: Air dry
Thickness of section: 30 µm

Soil Classification
U.S.: Fine, montmorillonitic, isohyperthermic Entic Chromustert

Physiographic position: Terrace plain between the Blue and White Nile Rivers
Topography and hill slope position: Broad plain
Parent material: Pleistocene flood plain sediments
Soil climatic data and/or soil water balance: Ustic moisture regime

Data for 35-mm slide
Magnification: 10 X
Light mode: Plane polarized

Nettleton, W. D. and J. R. Sleeman. 1 985. Micromorphology of Vertisols. p. 165-196. In L. A. Douglas and M. L. Thompson (eds.). SSSA Special Pub. 15, Soil micromorphology and soil classification. Soil Sci. Soc. Am., Madison WI
Soil Management Support Services. 1 982. Fifth international soil classification workshop, Sudan, 2-1 1 Nov., 1 982. USDA-SCS, Washington, D. C. and Soil Survey Administration, Democratic Republic of Sudan.
Source - W. D. Nettleton

Slide CT34. Soil Science Society of America, 1993. A Reference Slide Collection for Soil Micromorphology. SSSA, Madison, WI.