ABSTRACT

Three types of oolites, i.e., (1) spherical (2) hooked and (3) elliptical have been studied in the Bhander Limestone of the Maihar area, Madhya Pradesh, India. Spherical oolites are undeformed and the other two types are deformed. Hooked oolites (deformed) and undeformed oolites occur in the same thin section and have more or less similar lengths indicating that all the associated hooked oolites are derived from the collapse of spherical oolites due to agitation in water before deposition.

The intact internal structure of elliptical oolites shows that soft individual oolites did not suffer any collapse of their structure before deposition. The standard deviation of the length/breadth (L/B) ratios of the elliptical oolites is small, indicating uniformity of their shapes. From the similarity in their average size with the spherical oolites and uniformity of their L/B ratios, it may be suggested that elliptical oolites are probably also undeformed ones, their shapes being a result of a type of growth which took place faster in one direction (major axis) than in the other (minor axis).

A few elliptical oolites show book-like internal structure, i.e., new oolitic growth around collapsed oolites, a situation which proves that the deformation is definitely synsedimentary.