A OPEN PIT MINING AÇIK OCAK MADENCİLİĞİ

23 rd
Identification of Causal Relations of an Edge’s Sliding of an
Open Pit Mine
H. Hamdane
Department of Mining Engineering, Larbi Tebessi University, Tébessa, Algeria
M. Mellas,
Department of Civil and Hydraulic Engineering, University of Biskra, Algeria
ABSTRACT The slope movements represent a large diversified family; these movements
correspond to a major constraint for the mining works. The starting factors of the mechanical
processes in the beginning of instabilities must obviously be studied with precision. Indeed
they are represented in the upstream charts of events with sometimes dramatic consequences.
The objective of this paper is the identification of causal relations who allows judicious and
early interventions from the point of view of risk management.
The case of the landslide of Kef Essenoun, Who occurred in the phosphate’s open pit mine
of Djebel Onk (Algeria), presents the typical example of the negligence of geotechnical
studies which could prevent these risks. With this intention, traditional and numerical
methods will be applied for the determination of the probable causes of the landslide.
1 INTRODUCTION
The right design of open pit slope is an
important factor to insure the mine stability.
The planning of an open pit is a matter of
determining the most economic pit limit and
the most economical mining program for a
given mineralization (Steffen & al., 1970).
However, the stability aspects must have the
same importance that the economic aspects.
In many cases, it may be worthwhile to
conduct an optimization study (Coates,
1981), what was not made in the case of the
phosphate mine of Djebel Onk (sector: Kef
Essenoun); where the geotechnical aspect
did not take his true place at the time of the
opening of the mine; what led later to a
landslide. The study of the releases factors of
this slip it is proven valuable for the
comprehension of this phenomenon and the
prevention of this kind of catastrophe in the
future.
2 GEOLOGY OF THE SITE
The phosphate deposit of Kef Essenoun is
located on the southern side of the
Cretaceous anticline of Djebel Onk “Bir El
Ater, Tébessa, Algeria” (Figure 1).
Figure 1. Simplified geological map of
Djebel Onk
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