Ebook: Hydrogeophysics

and Hydrogeology 1 INTRODUCTION TO HYDROGEOPHYSICS 12 SUSAN S. HUBBARD and YORAM RUBIN 1 Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA 94720 USA. sshubbard@lbl. gov 2 Department of Civil and Environmental Engineering, UC Berkeley, Berkeley, CA 94720, USA In this chapter, we discuss the need for improved hydrogeological characterization and monitoring approaches, and how that need has provided an impetus for the development of an area of research called hydrogeophysics. We briefly describe how this research area has evolved in recent years in response to the need to better understand and manage hydrological systems, provide discussions and tables designed to facilitate navigation through this book, and discuss the current state of the emerging discipline of hydrogeophysics. 1. 1 Evolution of Hydrogeophysics The shallow subsurface of the earth is an extremely important geological zone, one that yields much of our water resources, supports our agriculture and ecosystems, and influences our climate. This zone also serves as the repository for most of our municipal, industrial, and governmental wastes and contaminants, intentional or otherwise. Safe and effective management of our natural resources is a major societal challenge.

This book is the first to cover the fundamentals of hydrogeophysics from both the hydrogeological and geophysical perspectives. Authored by leading experts and expert groups, the book starts out by explaining the fundamentals of hydrological characterization, with a focus on hydrological data acquisition, hydrological measurement analysis, and geostatistics. The fundamentals of geophysical characterization are then presented, with a focus on electrical resistivity, induced polarization, electromagnetic, GPR and seismic methods. The geophysical methods and petrophysical discussions presented here emphasize the theory, assumptions, approaches, and interpretations that are particularly important for hydrogeological applications. A series of case studies illustrate hydrogeophysical approaches for mapping hydrological units, estimation of hydrogeological parameters, and monitoring of hydrogeological processes in both the vadose and saturated zones. Finally, the book concludes with a discussion of hydrogeophysical frontiers, such as emerging technologies and stochastic hydrogeophysical inversion approaches.

Hydrogeophysics is intended to provide an introduction to students and to new researchers to the field, to be used as a resource for researchers already active in the field, and to serve as a springboard for advances in the field that are needed to improve our understanding and management of the earth’s shallow subsurface.