The branch of earth science which is concerned with the study of materials that the Earth is made of is known as geology. It attempts to describe the structure of the Earth and the processes which helped in shaping its structure. The subject of geology can be classified into petrology, structural geology, planetary geology, economic geology and engineering geology. One of the important aspects of this discipline is to determine the age of rocks. This is achieved by employing the principles of intrusive relationships, cross-cutting relationships, superposition, faunal succession and original horizontality. The dating systems studied under geology include radiocarbon dating, uranium-lead dating and argon-argon dating. Optically stimulated luminescence and cosmogenic radionuclide are some of the recent techniques used for dating surfaces and erosion rates. This book is a compilation of chapters that discuss the most vital concepts in the field of geology. The topics included herein on geology are of utmost significance and bound to provide incredible insights to readers. This book will serve as a reference to a broad spectrum of readers.