Building on the Legacy of a Man With a Vision

By L.P. Gough and J.R. Keith

Hansford T. Shacklette.

A major new USGS research study is being built on work that was begun by a creative individual, Dr. Hansford T. Shacklette, 40 years ago. Over a period of several years, he developed what is now the most highly requested dataset in the USGS Mineral Resources Program, containing "background" trace-element chemistry for 1,323 soil samples from the conterminous United States.

The fact that the dataset is available is thanks to the scientific imagination and persistence of Shacklette. Hans, as everyone called him, was always thinking ahead of his time. During the 1960s, he conceived of a project to collect soils from the lower 48 states for chemical analysis. As there was no funding for such a large project, Hans accomplished collection of the samples by using volunteers from the USGS. When USGS scientists, families, and friends headed off to do field work or on vacation they were asked to collect samples. He developed a way to collect representative, composite soil samples, using a standardized yet uncomplicated procedure. He was able to gather samples from about 1300 locations, resulting in a sample density across the country of approximately one sample collected every 50 miles. This effort, labeled "the 50-mile study," required coordination of literally scores of scientists for about 15 years.

The samples were ultimately analyzed for a broad spectrum of 40 major and trace elements utilizing the most up-to-date methods of the day. Hans conceived and carried out this project because he foresaw that such a database would be useful for many kinds of applications. He believed that understanding the geochemical baseline for soils was fundamental to recognizing and understanding changes in natural systems from both natural and manmade processes. The availability of broad regional geochemical information makes it possible to recognize patterns in the landscape. For example, recognizing the pattern of potassium levels in soil can help agronomists identify soil fertility patterns. Hans also pioneered studies showing a possible link between geology and human and animal health using the data that had been collected. For example, he was one of the first to use these data to look at regional trends in the environmentally important elements selenium, fluorine, arsenic, lithium, and cadmium.

Today, the soils dataset conceived and coordinated by Hans allows us to produce geochemical maps for specific elements, such as arsenic, that are of concern to land management and regulatory agencies. Determining the geochemistry of the Earth's surface involves understanding how the underlying rocks are affected by natural processes (such as weathering and erosion), as well as human activity, including industrialization, urbanization, mining, waste disposal, and agriculture.

After a lengthy career of numerous significant contributions to geochemistry, recognized by DOI Meritorious and Distinguished Service Awards, Hans retired from the USGS in 1979 to spend more time on his Kentucky farm, work in the family greenhouse business, and pursue his hobbies of rebuilding old Ford cars and raising a few beloved horses. He passed away in 1998, but we owe a great deal to his vision for the future.

A new effort is now underway, in cooperation with other State and Federal agencies and colleagues in academia, to carry out a higher-density national geochemical survey that will help to resolve questions raised by land management and regulatory agencies and to expand on the question Hans asked years ago--what are the broad, regional geochemical landscape trends for the country and what do they mean? Shacklette had that rare ability to anticipate future needs for science information; he approached his scientific field with boldness, energy, and originality, and we are still reaping the benefits of his creative thinking today.