DESCRIPTION OF COURSES

Close

SSAC 601 SOIL CLAYS AND CLAY MINERALOGY                                                                               (3L+1P) II

Objective
To impart the fundamentals of crystallography; structure, classification and identification of soil clays and clay minerals; their agricultural, industrial and environmental uses

Theory

UNIT I
Introduction and elements of crystallography; crystal morphology, constancy of interfacial angles, laws of rational indices, crystallographic axes, Miller indices, symmetry elements, point groups and space groups, crystal classes and systems.

UNIT II
Major geological formations of India; structure and identification of primary minerals; weathering of rocks and minerals, stability index.

UNIT III
Advanced structural features of clay minerals – stacking of 1:1 layers, tetrahedral rotation, thinning of octahedra, M1 and M2 sites, polytypes of mica, hydroxy interlayered minerals; transformation and synthesis of clay minerals and stability diagrams.

UNIT IV
Electrochemical properties of clay; infra-red analysis of clays and clay minerals; electron microscopic and XRD analysis of clay minerals; thermal analysis of clays; chemical and other methods of identification; computation of chemical formula.

UNIT V
Interaction of clay with humus, pesticides, heavy metals; characterization of clay-organic complexes; clay-water interaction.

UNIT VI
Non-crystalline clays in soil and their classification – old and modern; crystallinity of clays, paracrystalline and crystalline with defect; amorphous aluminosilicates, allophane, imogolite – synthesis and properties.

UNIT VI
Clay mineralogical composition of the Indian soils; role of clay minerals in plant nutrition.

Practicals
Separation of sand, silt and clay fraction from soil; identification and quantification of minerals in sand, silt and clay fraction; studies on acid clays; determination of specific surface area and CEC of clay; and estimation of smectite and vermiculite by CEC determination method.

Suggested Readings