Statistical estimation of the apex of a sediment distribution system from paleocurrent data |
| |
| Authors: | P E Jupp B D Spurr G J Nichols and J P P Hirst |
| |
| Institution: | (1) Department of Statistics, University of St. Andrews, KY16 9SS St. Andrews, Fife, Scotland;(2) Department of Geological Sciences, University of Liverpool, P.O. Box 147, L69 3BX Liverpool, England;(3) B.P. Petroleum Development Ltd., Kirklington Road, Eakring, Notts, England |
| |
| Abstract: | Precise statistical models are proposed for the distribution of paleocurrent directions in distributary systems. These models are based on a von Mises distribution for directions of paleocurrents in a system. The method of maximum likelihood is used to obtain an estimated position and confidence regions for the apex of the system. Both axial data (where only the trend of the paleocurrent is known) and directional data (where the direction of paleoflow is known) can be used. These models have been applied to two fluvial distributary systems in flat-lying Miocene deposits in the Ebro Basin, northern Spain. The estimate of the position of the apex of one of these systems is in good agreement with the position at the basin margin predicted from sedimentary facies information. The estimate of the position of the apex of the second system lies outside of the sedimentary basin; this result is considered to indicate that the distributary system had several feeder points along the basin margin, a situation which is predicted also from facies distributions. This statistical procedure can be used successfully on small data sets of around a hundred paleocurrent readings provided that they are scattered evenly across the area or lie in a wide arc. |
| |
| Keywords: | directional statistics distributary systems maximum likelihood paleocurrent von Mises distribution |
| 本文献已被 SpringerLink 等数据库收录！ |
|
