The book is a precise and comprehensive guide for the students and practitioners of organic and stable isotope geochemistry, and an interdisciplinary reference book for academia and Industry. It covers the fundamentals and applications of two important and interdisciplinary branches of earth science-organic geochemistry (the distribution and fate of organic matter) and stable isotope geochemistry (both traditional and non-traditional stable isotopes) used to study the conventional and unconventional energy resources and the ancient and modern earth environments and the changes therein. It includes illustrated and updated case studies on concepts and usage of geochemical proxies.