Studies of Tectonic Motion from Helwan-Satellite Laser Ranging Station

Gamal F Attia

doi:10.4236/ijaa.2014.44055

Abstract

Satellite Laser Ranging (SLR) is a proven space geodetic technique with significant potential for important contributions to scientific studies of tectonic motion. Currently, SLR is the most accurate available technique to determine the geocentric position with a reported precision in the order of few millimeters. Data gathered through SLR together with “Short Arc” mathematical algorithm became a highly precise tool to detect, monitor and calculate recent crustal movements through repeated measurements of the baselines between some stations on different tectonic plates. In this paper, the Short Arc mathematical model introduced in a previous paper was used to calculate the length of the baseline between Helwan-SLR station and other four fixed SLR stations, placed on different plates. Application of this model with the data gathered through a 4 year time interval gave repeatable results with very high accuracy (in the order of 4 cm).

Highlights

Geodesy is the science of measurement of the size, shape, rotation, and gravitational field of the Earth
A computer program was implemented for baselines calculations using the short-arc method and observational data of LAGEOS-1 during the year of 2000 as measured by Helwan Satellite Laser Ranging (SLR) station and other SLR stations
The short arc method does not depend on the dynamical models so strongly

Summary

Introduction

Geodesy is the science of measurement of the size, shape, rotation, and gravitational field of the Earth. Tectonic motions are largely slow and smooth in nature, with the exception of regions where earthquake activity is high A brief description of Helwan SLR station and the generation technique of the normal points, produced from the analysis of the observed satellites that have a line of sight are discussed. In one of our previous publications, a mathematical algorithm for the baseline determinations called the shortarc method was introduced and used to calculate the normal point data of satellites Lageos-1, observed during the year 1996, by Helwan SLR [4]. The basic concepts of short-arc method is briefly discussed and used to reproduce the normal points of the same satellite as observed during the year 2000 as observed by Helwan SLR. The set of new results are very near to the oldest which proves the repeatability of the technique as a whole over a very long time span

Helwan SLR-Station

Satellite LAGEOS-1

Normal Points Computed Using Helwan-SLR Data

Baseline Determination Using the Short-Arc Method

Results and Discussions

Conclusion