IDENTIFICATION AND COMPILATION OF LAVA TUBE RESOURCES AT CRATERS OF THE MOON NM: AIDING RESOURCE MANAGEMENT AND GEOLOGIC STUDY OF BASALTIC VOLCANISM

Craters of the Moon National Monument and Preserve on Idaho’s Eastern Snake River Plain encompasses several cinder cones and basaltic lava flows, some as young as 2,000 years old, that are the result of weakening of the crust along the Great Rift. The monument contains hundreds of lava tube caves and additional volcanic features, such as spatter cones, hornitos, pressure ridges, natural bridges, and lava trees. In recent years, more effort has been put toward the mapping, studying, and inventorying of these features. One objective of the Federal Cave Resources Protection Act of 1988 is to foster the exchange of information regarding cave resources between public service authorities, resource management offices, and scientific researchers. In accordance with this objective, an in-depth cave database has been developed using Microsoft Access and Geographic Information Systems, including ArcMap. Over 300 caves have been thoroughly mapped and catalogued, and the design of the database allows for efficient entry of new cave locations.

Database entries include the precise location, the number of levels, entrances, types of hazards, and mapping details of each cave. The geologic, biological, hydrologic, cultural/archaeological, and recreational value of each cave is also recorded, citing specific resources. This database provides valuable information pertaining to the populations of several species, including threatened bats. Compilation of biological resources aids in the protection of vulnerable animal populations and archaeological sites.

The locations, types, and features of lava tubes all impart valuable insight into mechanisms of basaltic lava flows. Mapping multiple cave locations reveals longer tube systems that can be correlated to specific flows. In addition, features within the lava tubes include lava stalactites, remelt features with a submetallic appearance, mineral deposits, flow terraces marking lava levels, floor squeeze-ups, bifurcating and merging channels, and skylights. The development of the cave database allows quick identification of caves with characteristics of geologic interest, fostering research into basaltic volcanism.