Hydrogeologic Factors Influencing Well Yields in Folded and Faulted Carbonate Rocks in Central Pennsylvania

Abstract

Hydrogeologic factors influencing well yields in folded and faulted Cambro‐Ordovician carbonate rocks and shales were investigated in central Pennsylvania. Productivity values (in gallons per minute per foot of drawdown per foot of saturated thickness) were obtained from 80 wells, the geometric mean value being 19.00, and were grouped into various categories according to well location. Productivities for the various categories were ranked and plotted against the percentage of wells on logarithmic probability paper. Parametric and nonparametric statistical tests were applied; the results of the nonparametric tests are presented. Fracture trace wells were more productive than nonfracture trace wells. Accidentally located fracture trace wells were as productive as intentionally located fracture trace wells because the accidentally located wells were clustered in more productive rocks. The success ratio of accidentally locating a fracture trace well is 4:6. Wells in sandy dolomite and coarse‐grained dolomites were the best producers; wells in valley bottoms were more productive than those in valley walls and uplands; anticlinal wells were better producers than synclina wells; and wells in beds dipping at less than 15° had higher yields than others. The Upper Sandy dolomite member and the Nittany dolomite have similar aquifer characteristics, which are significantly different from those of Bellefonte dolomite, limestones, and shales.

Resistivity method contribution in determining of fault zone and hydro-geophysical characteristics of carbonate aquifer, eastern desert, Egypt

“…Parizek (1976) showed that wells on lineaments (faults) in Pennsylvanian limestone produce more water than wells that are located away from lineaments. Wells on lineaments (faults) are more likely to produce water than wells that are off lineaments (Lattman and Parizek 1964;Siddiqui and Parizek 1971). For more details about the effect of lineaments and their relation with groundwater occurrences in karstic area, see Kazemir et al 2009 andFrohlich et al 1996.…”

Factors related to the water-yielding potential of rocks in the Piedmont and Valley and Ridge provinces of Pennsylvania

“…The relation of topographic setting to specific capacity has been reported for a set of 80 wells in carbonate rocks in Nittany and Penns valleys in central Pennsylvania (Siddiqui and Parizek, 1971) and fractured crystalline rocks in the Piedmont and Blue Ridge provinces of North Carolina (Daniel, 1989). Boxplots of 8 topographic settings (Figure 5a) confirm the earlier results that wells located in valley flats and flat surfaces tend to have higher specific-capacity values than wells located on hillsides or hilltops.…”

“…For comparison among hydrogeologic units, others have recommended that specific capacity should be adjusted for saturated thickness (Walton, 1962;Siddiqui and Parizek, 1971). The term "saturated thickness" is used by these investigators to mean the depth interval over which the well is open to the saturated subsurface.…”

“…Topographic setting has been shown (Siddiqui and Parizek, 1971;Daniel, 1987) to relate to specific capacity. The variable of casing depth is hypothesized to indicate thickness of regolith-the unconsolidated material overlying an aquifer that may be partially saturated.…”

Integrated studies for characterization of lineaments used to locate groundwater potential zones in a hard rock region of Karnataka, India

“…Areas upgradient of dykes or any other geological intrusions within the host rock are also good water potential zones, where the dyke/intrusion behaves as a barrier to groundwater flow. Lineament has generally been used as an indicative tool for locating groundwater potential zones (Lattman and Parizek 1964;Siddiqui and Parizek 1971;Yin and Brook 1992;Mabee et al 1994;Gustafsson 1994;Mahmood 1996;Sander 1997;Sander et al 1997;Edet et al 1998;Magowe and Carr 1999;Mabee et al 2002), but with the present scenario of over-exploitation of the aquifer, characterization of the lineament becomes essential to ensure the possibility of locating groundwater potential zones and managing over-exploited aquifers in hard rock terrain.…”