Monitoring of Offshore Platform Subsidence Using Permanent GPS Stations

Halim Setan, Rusli Othman

Department of Geomatics Engineering, Faculty of Geoinformation Science and Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia.

DOI:                 

Abstract

Offshore platforms undergo subsidence, especially due to production activities. The monitoring of such subsidence requires specialised technique (i.e. GPS) as the platforms are situated at sea (i.e. hundreds of kms from mainland). Unfortunately standard GPS processing procedure is unable to achieve the required accuracy (several cm) over long baselines. The research focuses on the development of processing strategy (i.e. estimation and subsidence analysis) for monitoring of offshore platform subsidence using three permanent GPS stations of the Malaysia Active GPS system (MASS). The estimation of each epoch employs Bernese GPS software, followed by subsidence analysis using in-house software. Preliminary results are also shown.

Keywords

Offshore platforms, GPS, Bernese GPS Software, Subsidence Detection

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Ashkenazi V. & Ffoulkes-Jones G. (1990) Millimeters over Hundreds of Kilometers by GPS, GPS World. November/December 1990.
[2]	Caspary W.F. (1987) Concepts of Network and Deformation Analysis, 1st. ed., School of Surveying, The University of New South Wales, Monograph 11, Kensington, N.S.W., 183 pages.
[3]	Chen Y.Q. (1983) Analysis of Deformation Surveys – A Generalized Method, Department of Surveying Engineering, University of New Brunswick, Technical Report No. 94, New Brunswick.
[4]	Chen Y.Q., Chrzanowski A. and Secord J.M. (1990) A Strategy for the Analysis of the Stability of Reference Points in Deformation Surveys, CISM Journal ACSGC, Vol. 44, No. 2 Summer 1990.
[5]	Setan H. & Othman R. (1998) Procedure of Detecting the Stability of Reference Stations for Monitoring of Subsidence, The 7th JSPS-VCC Seminar on Integrated Engineering, Universiti Malaya, Kuala Lumpur, 7-8 December, 1998.
[6]	Setan H. & Singh R. (2001) Deformation Analysis of a Geodetic Monitoring Network, Geomatica. Vol. 55, No. 3, 2001, pp. 333-346.
[7]	Krijnen K. & Hues H.de. (1995) Application of GPS with subcentimeter Accuracy for Subsidence Monitoring, Proceedings of the 5th International Symposium on Land Subsidence, The Haque, Netherlands, 16-20 October 1995, A. A. Balkema, Rottherdam, Brookfield.
[8]	Kuang S.-L. (1991) Optimization and Design of Deformation Monitoring Schemes. Department of Surveying Engineering, Report No. 157, University of New Brunswick, Fredericton, New Brunswick, Canada.
[9]	Kuang S.-L. (1996) Geodetic Network Analysis and Optimal Design: Concepts and Applications. Ann Arbor Press, Inc.: Chelsea, Michigan.
[10]	Leick A. (1995) GPS Satellite Surveying. Second Edition, John Wiley & Sons, Canada.
[11]	Rothacher M. and Mervart L. (1996) Bernese GPS Software Version 4.0. Astronomical Institute, University of Berne.
[12]	Wolf P.R. & Ghilani C.D. (1997) Adjustment Computations: Statistics and Least Squares in Surveying and GIS, 3rd. ed., John Wiley & Sons, Inc., New York.