FastXcorr : FORTRAN Program for Fast Cross-over Error Correction of Marine Geophysical Survey Data

FastXcorr : 해양지구물리탐사 자료의 빠른 교차점오차 보정을 위한 프로그램 개발

  • Kim, Kyong-O (Petroleum and Marine Resources Research Division, Korea Institute of Geoscience & Mineral Resonances) ;
  • Kang, Moo-Hee (Petroleum and Marine Resources Research Division, Korea Institute of Geoscience & Mineral Resonances) ;
  • Gong, Gee-Soo (Petroleum and Marine Resources Research Division, Korea Institute of Geoscience & Mineral Resonances)
  • 김경오 (한국지질자원연구원 석유해저자원연구부) ;
  • 강무희 (한국지질자원연구원 석유해저자원연구부) ;
  • 공기수 (한국지질자원연구원 석유해저자원연구부)
  • Published : 2008.04.28

Abstract

Many cross-over errors due to position errors, meter errors, observation errors, sea conditions and so on occur when marine geophysical data collected by own and other agencies are merged, and these errors can create artificial anomalies which cause an improper interpretation. Many methods have been introduced to reduce cross-over errors. However, most methods are designed to compare each point or segment data to find cross-over points, and require a long processing time. Therefore, FORTRAN program (FastXcorr) is presented to fast determine cross-over points using an overlap-sector, and to adjust cross-over errors using a weighted linear interpolation algorithm.

해양에서 관측되는 해양지구물리 탐사자료에는 위치오차, 기기오차, 관측오차, 해상 상태 등 다양한 원인에 기인하는 오차가 포함되어 있다. 이에 의해 한 기관에서 해양지구물리 탐사 자료를 취득할 때나 여러 기관에서 취득된 해양지구물리 탐사자료를 취합할 때 많은 교차점오차가 발생하고, 이러한 교차점오차는 부적절한 해석을 야기하는 인위적인 이 상대를 만든다. 교차점오차를 줄이기 위한 다양한 방법들이 제시되었지만, 이들 대부분의 방법들은 교차점을 찾기 위해 각각의 점자료(point data) 혹은 선분자료(segment data)를 모두 비교함으로써, 불필요하게 많은 계산시간을 요구하게 된다. 따라서 본 연구에서는 중복구역나눔 방법을 도입하여 빠르게 교차점을 찾고, 가중치선형내삽 방법을 이용하여 교차점오차를 보정하는 포트란(FORTRAN) 프로그램 (FastXcorr)을 개발하였다.

Keywords

References

  1. Kang, M.H., Han, H.C., Kim, K.O., Sunwoo, D., Kim, J.H. and Gong, G.S. (2006) EZXover: C program to Reduce Cross-over Errors in Marine Geophysical Survey Data. Korea Society of Economic and Environmental Geology, v.39, p.229-234
  2. Catalao, J. and Sevilla, M.J. (2004) Inner and minimum constraint adjustment of marine gravity data. Computer & Geosciences, v.30, p.949-957 https://doi.org/10.1016/j.cageo.2004.06.004
  3. Foster, M.R., Jines, W.R. and Weg, K.V. D. (1970) Statistical estimation of systematic errors at intersections of lines of aeromagnetic survey data. Journal of Geophysical Research, v.75, p.1507-1511 https://doi.org/10.1029/JB075i008p01507
  4. Hsu, S.K. (1995) XCORR : A cross-over techniques to adjust track data. Computer & Geosciences, v.21, p. 259-271 https://doi.org/10.1016/0098-3004(94)00070-B
  5. Johnson, R.H. (1971) Reduction of discrepancies at crossing points in geophysical survey. Journal of Geophysical Research, v.76, p.4892-4896 https://doi.org/10.1029/JB076i020p04892
  6. Mittal, P.K. (1984) Algorithm for error adjustment of potential field data along a survey network. Geophysics, v.49, p.467-469 https://doi.org/10.1190/1.1441681
  7. Prince R.A. and Forsyth, D.W. (1984) A simple objective method for minimizing crossover errors in marine gravity data. Geophysics, v.49, p.1070-1083 https://doi.org/10.1190/1.1441722
  8. Sander, E.L. and Mrazek, C.P. (1982) Regression technique to remove temporal variation from geomagnetic data. Geophysics, v.47, p.1437-1443 https://doi.org/10.1190/1.1441292
  9. Wessel, P. and Watts, A.B. (1988) On the accuracy of marine gravity measurements. Journal of Geophysical Research, v.93, p.393-413
  10. Wessel, P. (1989) XOVER: a cross-over error detector for the track data. Computer & Geosciences, v.15, p.333- 346 https://doi.org/10.1016/0098-3004(89)90044-7
  11. Yanger, H.L., Robertson, R.R. and Wentland, R.L. (1978) Diurnal drift removal from aeromagnetic data. Geophysics, v.47, p.1148-1156