Abstract

Small (less than 1 cm) elongate mud rip-up clasts within carbonate turbidite sequences were used as paleocurrent indicators in a Jurassic carbonate-slope environment. These slope deposits are exposed on Djebel Bou Kornine in northern Tunisia. The clast lineations were proved to be consistently parallel to flute-cast directions and consistent throughout the thickness of a turbidite bed. Growth faulting in this area during the Jurassic produced localized troughs between adjacent fault-blocks. Paleocurrent directions in these troughs were westerly, at right angles to the northerly slope of the continental margin. This type of lineated mud clast may be a useful paleocurrent indicator in oriented cores of certain turbidite sequences. 1) The long axes of small (less than 1 cm) mud rip-up clasts were found to be parallel to depositional paleocurrents and are, therefore, excellent indicators of ancient paleocurrent directions. 2) These paleocurrent indicators were used to confirm the existence of a trough between adjacent growth-fault blocks which trended parallel to the basin edge during the middle Jurassic in northern Tunisia. 3) Elongate muddy clast lineations can be valuable paleocurrent indicators to use alone or in conjunction with, for example, flute casts. They may be especially useful in oriented cores of turbidite sequences. Cores should be slabbed parallel to bedding and inspected for small muddy clasts whose axes are elongate and show some orientation.

First Page Preview

First page PDF preview
You do not currently have access to this article.