Established by Congress in 1879, the USGS was charged to describe the natural resources of the nation’s western public lands. By the early twentieth century the Survey had become one of the nation’s prominent natural science research agencies. Although geography’s role at the Survey diminished shortly after the turn of the century, USGS researchers at that time were conducting other basic theoretical research and applied problem solving that was at the cutting edge of geology, geophysics, geochemistry, hydrology, geomorphology, cartography, and (later) remote sensing.
By the 1990s, however, critics in Congress considered the USGS obsolete and proposed its abolition. A thorough public debate about the Survey and its role resulted in a dramatic revision of those proposals. USGS clients stepped forward to convince their congressional representatives that the Survey continued to serve the public. As a result, Congress decided not to eliminate the Survey but instead to broaden its purview with additional responsibilities. These additional responsibilities came with the integration of the National Biological Service and parts of the U.S. Bureau of Mines into the USGS.
SIDEBAR 1–1 The Critical Zone: Earth’s Surface and Near-Surface Environment
The surface and near-surface environment sustains nearly all terrestrial life. The rapidly expanding needs of society give special urgency to understanding the processes that operate within this Critical Zone (see figure below). Population growth and industrialization are putting pressure on the development and sustainability of natural resources such as soil, water, and energy. Human activities are increasing the inventory of toxins in the air, water, and land, and are driving changes in climate and the associated water cycle. An increasing portion of the population is at risk from landslides, flooding, coastal erosion, and other natural hazards.
The Critical Zone is a dynamic interface between the solid Earth and its fluid envelopes, governed by complex linkages and feedbacks among a vast range of physical, chemical, and biological processes. These processes can be organized into four main categories: (1) tectonics driven by energy in the mantle, which modifies the surface by magmatism, faulting, uplift, and subsidence; (2) weathering driven by the dynamics of the atmosphere and hydrosphere, which controls soil development, erosion, and the chemical mobilization of near-surface rocks; (3) fluid transport driven by pressure gradients, which shapes landscapes and redistributes materials; and (4) biological activity