This collection of 60 short papers on subjects in the fields of geology, hydrology, topography, and related sciences is the third of a series to be released during the year as chapters of Professional Paper 450. The papers in this chapter report on the scientific and economic results of current work by members of the Geologic, Water Resources, and Topographic Divisions of the United States Geologicai Survey. Some of the papers announce new discoveries or present observations on problems of limited scope; other papers draw conclusions from more extensive or continuing investigations that in large part will be discussed in greater detail in reports to be published in the future.

Chapter A of this series, to be published later in the year, will present a synopsis of results from a wide range of work done during the present fiscal year.