Using Geophysical Methods to Image Near-Surface Cylindrical Pipeline: A Case Study on Engineering Applications, Jordan

Abstract

Conventional and modern geophysical methods have become presently very popular and reliable tools to investigate the near- surface underground features for different applications, such as engineering, geotechnical, environmental and groundwater aquifer characterization. Geophysical prospecting techniques have gained great importance due to their non-invasive, cost- effective and fast field implementation. In this research, a geomagnetic survey and an electrical resistivity survey were used to investigate the magnetic and electrical resistivity anomaly responses and imaging of an underground Gas Pipeline (GPL). This GPL is in fact part of a major multinational project to transport gas from Egypt to Jordan and then to Syria, Lebanon and Turkey. Thus it crosses Jordan from Aqaba in the south to the Jordanian-Syrian borders in the north. The two geophysical methods were successful in locating and imaging the underground GPL down to depths of 1 to 4 meters within different soil materials. The geophysical response revealed the GPL in terms of its dimensions and extension. In addition, the geoelectrical study proved to be an effective tool in mapping the subsurface lithology variations and shallow structural features such of interest (e.g. fractures, crakes and joints). Thereby, this shows the advantages of geophysical techniques in identifying the optimum site for excavation in case of any encountered trouble that could occur in a similar sub-surface engineering construction, in terms of reducing the amount of excavation to be made.