Carbonate aquifers: Distinctions between conduit flow or diffuse flow should be abandoned in their classification and design of monitoring systems

Conference · Wed Jan 01 00:00:00 EST 1992 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5806476

Davies, G J ^[1]; Quinlan, J F ^[2]; Worthington, S R.H. ^[3]

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1. Ozark Underground Lab., Protem, MO (United States)
2. Quinlan and Associates, Nashville, TN (United States)
3. McMaster Univ., Hamilton, Ontario (Canada)

For more than 20 years most karst hydrogeologists have thought that karst aquifers could be classified within a continuum characterized by two end-members, conduit-flow and diffuse-flow, and that these aquifer types could be reliably identified by interpretation of long-term measurement of variations in water hardness (or specific conductance) and temperature. From the work of Newson (1971), Worthington (1991) and the senior author's 16-month study of 11 springs in the Knox Dolomite in Tennessee, it is clear that variations in specific conductance are an indicator of percentage of spring discharge that is point-recharge via swallets and other open sinkholes (rather than dispersed recharge as infiltration through soil). Variations in water temperatures indicate changes in the relative proportions of quick-flow and slow-flow components. Neither of these parameters is an indicator of proportions of conduit flow or diffuse flow. Also, the meaning of these latter terms has evolved and become too ambiguous. Observation of many cave streams leads to the conclusion that conduit flow and diffuse flow exist at the local scale (100 m); at any larger scales, mixed flow always occurs. In the light of recent knowledge any ground-water monitoring strategy based upon the presumed presence of diffuse flow versus conduit flow in any karst aquifer and that attempts distinction between them is unreliable.

• OSTI ID: 5806476
• Report Number(s): CONF-921058-; CODEN: GAAPBC
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 24:7; Conference: 1992 annual meeting of the Geological Society of America (GSA), Cincinnati, OH (United States), 26-29 Oct 1992; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
54 ENVIRONMENTAL SCIENCES
AQUIFERS
HYDROLOGY
GROUND WATER
MONITORING
TENNESSEE
CARBONATE ROCKS
CLASSIFICATION
ERRORS
FLOW RATE
FLUID FLOW
DEVELOPED COUNTRIES
HYDROGEN COMPOUNDS
NORTH AMERICA
OXYGEN COMPOUNDS
ROCKS
SEDIMENTARY ROCKS
USA
WATER
580000* - Geosciences
540210 - Environment
Terrestrial- Basic Studies- (1990-)