DACIAN BASIN - GeoEcoMar

The large and continuous rock exposures on an approximately 1000 m distance
in the Jilţ South Quarry revealed a sand body with lateral accretion sedimentation
surfaces (as defined by Thomas et al, 1987) representing a point bar unit.
The Jilţ South Quarry is located in the village Mătăsari, circa 10 km ESE of Motru
town, in western Oltenia (Fig. 7.1). The Jilţ River, a tributary of the Jiu River, gives the
name of the quarry.
Since 1989, the study of the point bar in the Jilţ Quarry exerted an attraction for
sedimentologists from the Geological Institute of Romania. Thomas Ryer, who visited
the Jilţ Quarry in 1991 and pointed out the special development of the point
bar deposits, revitalized this interest. As a consequence, most of the mining front
where the point bar deposit cropped out was completely cleaned on 800 – 900 m
length and around 15 m height (Fig. 7.2). In this way an extensive photographic
documentation was made possible, together with a detailed mapping of the mining
front. As this was advancing, additional observations were made several years
after the main mapping stage.
The sedimentological description of the Jilţ point bar was first presented by
Jipa et al. (1992). The subject was approached by Jipa (1994) and recently by Jipa
et al. (2006).
7.1. THE gEOLOgY OF THE JILţ QUARRY AREA
The Jilţ Quarry is located in the area of Late Neogene deposits of the Dacian Basin,
on the eastern part of a large anticline. In the Jilţ mining area, the Late Neogene
deposits are dipping to the south a few degrees.
According to Stănescu et al. (1983; manuscript) 1 the sedimentary sequence in
the Jilţ Quarry area (Fig. 7.3) starts with a sandy horizon of 90-150 m thickness attributed
to the Getian. The coal strata III and IV are included in this sequence. The
1 Stănescu, T., Vlădescu Ang., Vlădescu, A., Slăvoacă, I., Arion, P. (1983) - Sinteza datelor obţinute prin
lucrările de prospecţiuni si explorări geologice efectuate pentru cărbuni în depresiunea getică, perimetrul
Jilţ-sud, Jud. Gorj. I.P.G.G., unpublished geological report (in Romanian), Fondul geologic, Bucureşti.
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Chapter 7
THE POINT BAR FACIES IN THE JILţ QUARRY
(ROMANIAN DEPOSITS): A MODEL
OF LATERAL FLUvIAL SEDIMENTATION