الفهرس 
ch 1 : INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 191 |  |  |
| | | from | 191 | | |
Abstract
The main aim of this study is the comparison among all gravity reduction methods are used to reduce the gravity for determining the geoid in Eygpt. Which is considered the most important geodetie application. These methods are :
Free-air reduction, Bouguer reduction, Isostatic reduction and Helmert reduction. For doing this study, a computer programs were used for calculating the gravity anomalies for all gravity reduction techniques, and also for calculating the geoid for Egypt. Data used are gravity observations, digital terrain model for Egypt and constat density of 2.67 g/cm3.
The results show that, isostatic gravity reduction ( pratt – Hay ford Airy He is kanen ) is the best method for reduction where it gives gravity anomalies that are small, smooth and slightly osculating around zero but the indirect effect in partt Hay ford isostatic reduction on gravimetric quantities slightly large