THE MEDITERRANEAN LOWER CRETACEOUS

Khrischev (Николов, Хрисчев, 1965b), etc. Data obtained more recently
will be presented here.
In the Salas syncline, as well as in Mihajlovgrad District near Blagovo village,
Pâstrinata hill, the villages Stubel and Pali Lula, in the Ciren, Ponor, Gorno Pestene
and Goljamo Pestene areas (Salas — Ciren zone) the Berriasian is represented
at its base by the light grey micritic limestones of the Glozene Formation, and higher
up by the clayey-calcareous sediments of the Salas Formation.
Pseudosubplanites cf. combesi Le H é g. was discovered in the upper part of
the Glozene Formation, in the valley of the Sugavica river (the southern slope of
Pâstrinata). This species is characteristic for the base of the Berriasian. This ammonite
find, as well as the identified Berriasian calpionellids from the upper part of the
Formation found in numerous boreholes (B a k a 1 о v a et al., 1976), indicate that
the upper part of the Glozene Formation is of Berriasian age (H и ко л о в, Сапунов,
1970).
In some places in the SalaS syncline the upper part of the Glozene Formation
is denuded and Hauterivian sediments overlie the Berriasian (Celjustnica, Beli
Mel and Prevala).
The following ammonite taxa, characteristic of the Malbosiceras paramimounum
Subzone of the Fauriella boissieri Zone: Malbosiceras paramimounum (M a z.),
Jabronella (Erdenella) erdenensis N i k., Fauriella boissieri (P i с t.), Berriasella
sp., Spiticeras spp., etc., are found on the northern slope of Pâstrinata hill, in the
eastern part of the Erden quarries (to the south of Bojcinovci), at a distance of
40-50 m from the base of the Salas Formation.
The presence of the Berriasian has also been proved in the sections to the west
of Krapcene village, Mihajlovgrad District, as well as to the southwest of Ljuti
Dol village and around the Ràzdavec and Djakovci neighbourhoods, Vraca
District. Leptoceras studeri (О о s t.), Berriasella sp. indet. and Bochianites sp.
indet. have been identified in the recent outcrops, indicating Late Berriasian
Berriasian microfauna (foraminifera and calpionellids) are found in a number
of boreholes in this region.
In the more southern zone (the villages of Zamfirovo — Glavaci — Beli Izvor—Kalen
— Veslec — Besovica—• Drasan — Reselec) the Berriasian is connected
mainly with the massive micritic, irregular recrystallized, allochemical or
biomorphic limestones of the Brestnica Formation, partially with the upper part
of the Glozene Formation (R-l Zamfirovo), or partially with the Sala§ Formation
as well (e. g. R-17 Beli Izvor), whereas to the north in the boreholes of the Vârbica
area — with the transitional sediments of the Brestnica-Salas Formation
(B a k a 1 о v a et al., 1976).
Interesting calpionellid successions occur in borehole R-l Reselec, where the
following zones and subzones were demonstrated at three levels: in the interval
2965—3038 m (Salas Formation) — T. carpathica Subzone of the Calpionella Zone;
at 3128-3130 m (Brestnica Formation) — C. alpina Subzone of the Calpionella
Zone; at 3132.40 m — Crassicollaria Zone. These findings show that the Jurassic-
Cretaceous boundary in this section passes through the lower part of the Brestnica
Formation. It should be noted for comparison that the thickness of the Brestnica
Formation at R-l Reselec is 140 m, being 502 m at R-17 Beli Izvor. Consequently,
the position of the Jurassic-Cretaceous boundary in the Brestnica Limestone Formation
does not depend on the thickness of the Formation, but it is influenced by the
position of the section with respect to the body of the Formation, as has been found
by S a p u n о v (in В a k a 1 о v a et al., 1976).
Generally speaking, the Berriasian in the Western Fore-Balkan is relatively
homogeneous, connected, on the one hand, with the pelagic facies of the Glozene
4 The Mediterranean Lower Cretaceous 49