Hereby I am mentioning the list of colleges where you can apply . The list consist of colleges providing B.Sc in Geology in Tamil Nadu :

COLLLEGS IN TAMIL NADU

KUMARAGURU COLLEGE OF LIBERAL ARTS AND SCIENCE , COIMBATORE

THIRU A. GOVINDASAMY GOVERNMENT ARTS COLLEGE

PRESIDENCY COLLEGE

JAWAHAR SCIENCE COLLEGE

NATIONAL COLLEGE , TRICHY

A.D.M. COLLEGE FOR WOMEN

THIRUVALLUVAR UNIVERSITY

V.O. CHIDAMBARAM COLLEGE

GOVERNMENT ARTS COLLEGE , SALEM

GOVERNMENT ARTS COLLEGE , KARUR

Hope it helps!

All the best for your future!