Cave Features: Information Concerning the Nature and Genesis of Soils
1970
Fanning, D. S.
Information about soils may be obtained from speleology, the study of caves. Some caves are shallow enough for roots of surface plants to be present in them. Cave maps and the distribution of stalactites on cave ceilings show that rock structure strongly controls the pattern of water movement through soil-rock columns. Relatively pure samples of some secondary minerals, formed at temperatures similar to those in the lower parts of overlying soils, may be obtained from caves. Dolomite seldom forms in caves, but calcite and aragonite are common. Impurities, including quartz, clay minerals, and iron oxides, are present in carbonate speleothems. Many speleothems have repeating growth increments (segments, rings). Some of these may be annual. When understood, they may give clues to, and dramatically portray, seasonal changes in the rate of flow and the composition of percolating waters. Studies of percolating waters from undisturbed soil-rock columns could be made using caves, but it would be difficult to tell what area and volume of soil and rock contributed to the percolate.
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