Showing papers on "Sinkhole published in 1982"

Sinkhole Development Resulting from Ground-Water Withdrawal in the Tampa Area, Florida

Abstract: From introduction: The purpose of this study is to define causes of sinkhole development in an area north of Tampa (Florida) (fig. 1), particularly the relation of geology, hydrology, and hydrologic changes to the type and severity of subsidence or collapse.

Spatial analysis of a karst depression population: Clues to genesis

Abstract: A detailed analysis of depression spatial distribution on the parts of the Western Highland Rim and Pennyroyal Plain underlain by the St. Louis and Ste. Genevieve Limestones indicates the presence of a depression infrastructure. The major geomorphic elements of the infrastructure include depression density (no./km 2 ), doline swallet order, and interdoline spacing. A multigenerational diffusion and competition process model best explained: (1) the presence of two lognormally distibuted depression density subpopulations; (2) discrete, clustered depression sets containing second-order swallet dolines surrounded by first-order swallet depressions; (3) geomorphic competition between adjacent second-order swallet dolines for runoff and catchment area; and (4) a positive correlation between interdoline rim spacings of the small swallet order and the sum of their respective major axial lengths.

Evaporite dissolution and development of karst features on the rolling plains of the texas panhandle

Abstract: More than 400 dolines, consisting of collapse sinkholes and closed depressions, occur in Hall and Briscoe Counties, Texas. Of these, at least 36 sinkholes and two depressions formed between 1940 and 1972. Collapse sinks are typically circular and range up to 100 m in diameter and 15 m in depth. Closed depressions are irregularly-shaped, internally-drained depressions up to 2.4 km in length. Surface fractures up to 1.5 km in length are associated with certain closed depressions. Karst features are forming as a result of intrastratal dissolution of Upper Permian evaporites, primarily halite and secondarily gypsum. Salt dissolution and overburden collapse are evident from geophysical log cross-sections and occur at depths ranging from 195 to 275 m. Dissolution is progressing down dip and mean dissolution rates for salt beds in the Hall County area range from 0.29 to 7.73 cm/yr. The valley of the Prairie Dog Town Fork of the Red River is an area of ground-water discharge for flow systems moving eastward from topographically high areas of the Rolling Plains and from the eastern rim of the High Plains. Halite beds in contact with these waters undergo dissolution. Salt springs and brine seeps, some associated with sinkholes and depressions, occur in the discharge area and indicate that dissolution is an ongoing process.

Quaternary interglacial and associated deposits in southwest Newfoundland

Abstract: A coastal cliff section near Codroy, Newfoundland exposes five distinctive lithologic units, which are defined lithologically and structurally as colluvial, lacustrine, or glacial in origin. They have been preserved in a gypsum karst depression, but continuing karst evolution has disturbed their original attitudes.The two oldest units, 5 and 4, were formed by sidewall slumping of local bedrock and earlier glacial material from the failing rim of a newly formed sinkhole. Unit 3 represents tranquil sedimentation of thin sand and silt–clay laminae, first in a freshwater sinkhole pond, then in brackish marine waters that entered after breaching of its seaward wall, and finally again in fresh water as sea level fell below the sill of the small embayment. Units 2 and 1 are glacial deposits laid down over older units after a second major sinkhole collapse. Collapse has continued to the present day.Pollen and spores from unit 3 indicate that during its deposition regional vegetation changed from tundra (Zone A) t...

Groundwater pollution prevention in southeast Minnesota's karst region [Aquifers, sinkholes, includes agricultural waste and pesticides contamination]

Abstract: 19 pages; includes photographs and drawings. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu.