Spelling suggestions: "subject:"north central utan""
1 |
Hydrogeology and Hydrochemistry of Springs in Mantua Valley and Vicinity, North-Central UtahRice, Karen C. 01 May 1987 (has links)
Chemical and tritium analyses of groundwater, precipitation and discharge records, fracture orientations, lineaments, and structural, stratigraphic, and topographic relationships have been used to describe the groundwater systems of Mantua Valley, north-central Utah. Groundwater flows through fractured Paleozoic quartzites and carbonate rocks and discharges from eleven perennial springs in Mantua Valley. Permeability in quartzites is the result of intense faulting and jointing. Groundwater in carbonate aquifers flows through fractures and/or fractures modified by solution and discharges as relatively large springs (up to 227 liters per second). Neogene normal faulting, rather than extensive karst processes, has produced valleys which are closed or nearly closed to surface-water drainage. Groundwater in the area has relatively low total dissolved solids, is warmer than the mean annual air temperature, and is of the calcium-magnesium-bicarbonate type. Temperatures of the groundwater suggest circulation depths in excess of 10 to 185 meters. Intermittent turbidity and fluctuations in calcite and dolomite saturation indices and in groundwater temperatures suggest that springs may be supplied by mixtures of shallow and deeper groundwater flow. With the methods used here, a water budget analysis of the area indicates that recharge to the groundwater systems is approximately 49% of mean annual precipitation. Annual recharge and average discharge of the springs were used to calculate recharge areas, which range from 3.0 km2 to 18 km2. Tritium analyses of two of the springs suggest mean residence times of less than ten years.
|
2 |
Petrology of the Lower Middle Cambrian Langston Formation, North-central Utah and Southeastern IdahoButterbaugh, Gary Jay 01 May 1982 (has links)
The Lower Middle Cambrian Langson Formation was studied in the xi Bear River Range of north-central Utah and southeasternmost Idaho and the Wellsville Mountains of north-central Utah. The depositional textures and sedimentary structures preserved within the rocks were compared with characteristics of similar modern sediments and ancient rock to determine environments of deposition, paleogeography, diagenetic alteration and pattern of dolomitization.
The rocks of the Langston Formation were divided into eleven different rock types. These eleven rock types were formed within four recognizable lithofacies: 1) upper peritidal; 2) inner carbonate shelf; 3) inner clastic shelf; and 4) outer clastic shelf.
The general depositional environment is inferred to have been a shall ow subtidal to subaerial carbonate shoal complex. Clastic sediments from the east and north or northwest periodically prograded over the carbonate complex during times of relatively slow subsidence. The deposition of the Langston Formation mudrocks and carbonates occurred during the first Cambrian grand cycle.
Eogenetic diagenetic features include birdseye structures, relict evaporite structures, fibrous rim cement, compaction, and the begining of dolomitization. Mesogenetic diagenesis is characterized by dolomitization and pressure solution. Telogenetic diagenesis is limited to fracturing and calcite infilling.
Dolomitization is believed to have resulted mainly from downward reflux of hypersaline brines, as indicated by relict evaporite structures, zoned dolomite rhombs, and a general association of dolomite with upper peritidal facies. The hypersaline brines formed in the upper peritidal environment, and percolated downward through underlying porous sediments. The greater density of the hypersaline brines displaced less-dense interstitial fluids. These brines were periodically diluted by normal marine water or fresh water.
|
Page generated in 0.1171 seconds