Geology Reports⌕ Search

Geology topics

T. E. Reilly

Publications and source records attributed to T. E. Reilly.

22 records · Page 2Linked to original sources
USGS1984

Definition of boundary and initial conditions in the analysis of saturated ground-water flow systems; an introduction

Accurate definition of boundary and initial conditions is an essential part of conceptualizing and modeling ground-water flow systems. This report explains the properties of the seven most common boundary conditions encountered in ground-water systems and discusses major aspects of their application. It also discusses the significance and specification of initial conditions and evaluates some common errors in applying this concept to ground-water system models. (USGS)

Open-File Report↗
USGS1984

The principle of superposition and its application in ground-water hydraulics

The principle of superposition, a powerful methematical technique for analyzing certain types of complex problems in many areas of science and technology, has important application in ground-water hydraulics and modeling of ground-water systems. The principle of superposition states that solutions to individual problems can be added together to obtain solutions to complex problems. This principle applies to linear systems governed by linear differential equations. This report introduces the principle of superposition as it applies to groundwater hydrology and provides background information, discussion, illustrative problems with solutions, and problems to be solved by the reader. (USGS)

Open-File Report↗
USGS1983

Effects of sanitary sewers on ground-water levels and streams in Nassau and Suffolk Counties, New York, part 1: Geohydrology, modeling strategy, and regional evaluation

A computer simulation of Long Island 's regional groundwater system has been used to evaluate the effects that new-installed sewers will have on ground-water levels. Results indicate maximum water-table decliners of as much as up to 18 feet in central Nassau County and about 9 feet in Suffolk County. Total stream base flows and freshwater outflow to the south shore bay system will decrease by 22%. The regional scale of the model does not permit detailed predictions for individual streams. To quantify the effects of lowered ground-water levels on individual streams, two fine-scale sub-regional models have been designed. This report, the first in a three-part series describing the simulated effects of sewers in southern Nassau and southwestern Suffolk Counties, presents the hydrogeologic setting, pertinent literature, modeling strategy, subregional model design, and the results obtained to date from the regional ground-water model. The regional model results described will be used in the later reports to generate flux boundary conditions for the subregional models.

New York↗