Dolny dewon z otworu wiertniczego Andrychów 4

Abstract

LOWER DEVONIAN IN BORE HOLE ANDRYCHÓW 4SummaryBore hole Andrychów 4, completed in June 1967, made at Sułkowice near Andrychów (Fig. 1), pierced the overthrust flysch formations and autochthonous Miocene deposits at a depth at l625 m. The bore hole revealed the following section of the Palaeozoic substratum: 1625.0-1657.0 m - marginal beds of productive Carboniferous, 1657.0-1672.0 m - probably Visean (lack of drill core), 1672.0-1761.0 m - Famennian, 1761.0-1876.0 m - Frasnian, 1876.0-2035.0 m - Givetian, 2035.0-2229.0 m - Eifelian, 2229.0-2378.5 m - Lower Devonian (Emsian), 2378.5-2425.0 m – metamorphic formations. As proved by the bore hole considered, the Lower Devonian formations are developed as sandstone-siltstone series, 149.5 m in thickness, underlain with metamorphic formations (Fig. 2). Like in other bore holes of this region, the series are divided into three parts (K. Konior 1965, 1966). The upper part 31.1 m in thickness (depth 2229.0-2260.1 m) consists mainly of coarse-grained and conglomerate-like sandstones with intercalations of dark grey siltstones (Table I, Figs. 3 and 4, Table II, Figs. 5 and 6). One of these intercalations reveals, at a depth of 2247.2-2247.4 m psilophyte flora remains (Table V, Figs. 11, 12 and 13, Table VI, Fig. 14, Table VII, Fig. 15). Middle part, 80.7 metres in thickness (depth 2260.1-2340.8 m) is developed as fine-grained and middle-grained, mainly “sugar” sandstones (Table III, Figs. 7 and 8). At a depth of 2288.0-2317.5 m, they include sandstones with slightly marked worm tubes, which might be determined as pseudoscolithus sandstones (Table IX, Fig. 19). They are not related to the scolithus sandstones found in bore hole Andrychów 3 (depth 2223.8-2265,0) made at a distance of about 5.7 km from bore hole Andrychów 4.The lower part consists almost exclusively of coarse-grained and conglomerate-like sandstones (Table IV, Figs. 9 and 10). A considerable differentiation in thickness, amounting in the area Bielsko - Andrychów to 103 metres, points to a distinct configuration of the metamorphic-crystalline basement. Metamorphic formations pierced by bore holes made in the area Bielsko - Andrychów, and microscope examinations made by W. Heflik of optic properties of quartz show that the alimentation area, supplying quartz material to the Lower Devonian deposits in the area considered, was built up of both acid deep rocks and metamorphic rocks. The metamorphic rocks occurred in the vicinity of the region of sedimentation, whereas the deep rocks appeared at a greater distance. The sedimentation was of diversified character, frequently turbulent and chaotic. The formations of Lower Devonian age found in the region Bielsko – Andrychów may be of scientific and of practical importance mainly in search for oil and gas deposits.