Micromorphology and Mineralogy of Gullied Soils in Anambra State, Nigeria

Detailed studies on the micromorphology and mineralogy of two gullied soils in Anambra State of Nigeria were carried out. Thin sections were prepared and point counting technique used in investigating the pedological features. Micromorphological analysis indicates that the S-matrix of the soil have mainly sepie and inundulic with few asepic plasmic fabric. Distribution patterns are agglomeroplasmic to porphyroskelic and granular. Clay mineralogy was determined by x-ray diffractometry and the result reveals that the soils are mostly dominated by kaolinite and quartz. Macromorphologically, the soils are very deep, well drained and coarse to medium textured with granular and medium subangular structures. The occurrence of ferriargillans in the B-horizon is a strong indication of pedotranslocation. Other contemporary processes or regrouping phenomena are pedotranslocation, pedoturbation, pedocompaction and pedotransformation of minerals. The role of clay mineralogy type in soil erosion problems is discussed.