Identification of Recharge Areas Using Geochemical Factor Analysis

Abstract

Factor analysis is useful for interpreting commonly collected ground‐water quality data and relating those data to specific hydrogeologic processes. One hundred nine ground‐water quality samples from wells completed in the upper Floridan Aquifer near Live Oak, Florida were analyzed for major dissolved constituents. R‐mode factor analysis was used to separate those chemical variables that reflect areally‐significant recharge processes from those related strictly to the dissolution of aquifer materials. Areas impacted by direct, rapid, artificial recharge through drainage wells and sinkholes, as well as by slow, natural recharge into the Floridan Aquifer, were delineated. Four factors which represent different chemical processes were identified and their relative areal impact determined. These processes are: (1) regional dissolution of the aquifer limestone, (2) dissolution and ion exchange in the discontinuous, semipermeable layer that overlies portions of the aquifer, (3) and (4) recharge from local, urban and agricultural runoff.

Identification of groundwater chemistry origins in a regional aquifer system (Wielkopolska region, Poland)

“…One disadvantage of FA, however, is the difficulty of distinguishing the processes that cause similar variations in the groundwater chemistry (Olmez et al 1994). In addition, a priori knowledge of the hydrogeologic processes affecting the environment under investigation is required for an effective application of FA (Lawrence and Upchurch 1983).…”

Use of Factor Analysis to Identify Sources Controlling Groundwater Chemistry in The Shallow Coastal Plain Aquifer, Western Saudi Arabia

“…This may contribute to the releasing of Fe 2+ and SO 4 2-into the groundwater. The moderate negative loading of NH + 4 in this factor may indicate less oxygenated pathway owing to oxidation of pyrite (Lawrence and Upchurch 1982). .…”

“…Over the past 30 years, Factor analysis (FA) has been successfully used to sort out the hydrochemical processes and relationships of collected groundwater data (Morin et al, 1979, Lawrence andUpchurch, 1982;Saad and Turgeon, 1988;and Deverel 1989). The goal of FA is to simplify the quantitative description of a system by determining the minimum number of new variables necessary to reproduce various attributes of the data.…”

“…In the presence of substantially large amount of base information concerning the groundwater chemistry, and the limitation associated with the classical graphical approaches, which often allow using a finite number of variables (Ashley and Lloyd, 1978;Dalton and Upchurch, 1978;and Lawrence and Upchurch, 1982), multivariate techniques may be useful and come into consideration as an essential tool because the relative importance combinations of chemical and non-chemical variables can be evaluated.…”

Evaluation of major factors influencing the geochemistry of groundwater using graphical and multivariate statistical methods in Yenagoa city, Southern Nigeria

“…Ashley and Lloyd (1978) used factor analysis to evaluate the hydrogeochemical process in the Santiago basin of Chile and the Derbyshire Dome of England. Lawrence and Upchurch (1982) also used the technique to delineate the zones of natural recharge to groundwater in the Florida aquifer. Ruiz et al (1990) suggested that the basic purpose of such an analysis was to study the hydrogeochemistry of aquifers by simplifying the numerous and complex groundwater data into a set of factors, few in number which can explain a large amount of the variance of the analytical data and also indicate the source of origin of various ions present in water.…”