DACIAN BASIN - GeoEcoMar

7.1. The geology of the Jilţ Quarry area
overlying Dacian deposits consist of clay and sand intercalated with the lignite
beds V, VI and VII.
The 70 - 90 m thick Romanian Jilţ sequence consists of clayey and sandy deposits
with fresh-water fauna. The lignite beds VIII – XII are intercalated in these
deposits. The overlying Early Pleistocene clay hosts the lignite beds XII and XIV. According
to Stănescu et al. (1983; manuscript) 1 , the Dacian/Romanian limit is located
in between the VII and VIII lignite strata. Pană et al. (1981) consider that the Early
Romanian (Siensian) starts above bed V and the sandy interval VII – VIII is in the
middle of the Siensian interval.
The Jilţ sand body that displays a coarser and thicker (up to 35 m) western part,
overlaid by large scale inclined stratification sand (Fig. 7.4), was investigated for its
point bar facies.
The point bar deposits are cropping out in the vertical walls of two mining
fronts (Fig. 7.5), in the southern part of the Jilţ mining area. The upper part of the
investigated sand body appears in the coal extraction front E13 and the basal part
of the studied deposits crop out in the immediately lower mining horizon (E 12).
The Jilţ point bar deposits are overlying a silty-clay level, which covers directly
the lignite bed VII. An association of fresh-water mollusks was collected from this
clay horizon. The basal clay horizon shows significant thickness variations (between
1.5 and 5 m) in the western part of the extraction front, generated by differential
erosion due to the fluvial currents that deposited the Jilţ sand.
1 Op. cit., p 140
FIGURE 7.1. Geographic location of Jilţ Quarry
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