Труды геологического института. Выпуск 596. Paleozoic ichnology of St. Peterburg Region: Excursion Guidebook / Путеводитель палеозойской ихнологии окрестностей Санкт-Петербурга

The St.Petersburg region is located at the transition between the southern slope of the Baltic shield and the northern slope of the Moscow basin. Like northern Estonia, it belongs to the Baltic monocline where relatively undisturbed Vendian and Lower Palaeozoic strata are almost flat-lyingwitha slight dip (2.5–3.5 m per km) to the south. The thickness of the Lower Paleozoic sequence in the StPetersburg region ranges from 220 to 350 m (Cambrian: 120–150 m; Ordovician: 100–200 m).

Ordovician carbonate rocks in the vicinity of St. Petersburg occupy an elevated area called the “Ordovician (Silurian) plateau”. Theplateau, as can be seen on the geological map, consists of two parts (Fig. 1). The western part is called the “Izhorian plateau” and the eastern part the “Volkhovian plateau”. The Ordovician plateau is bounded in the north by a prominent naturale scarpment known as the Baltic-Ladoga Glint (Lamansky, 1905) or the Baltic Glint (Tammekann, 1940). The main natural outcrops of Middle Cambrian-Lower Ordovician rocks in the region follow the line of the Glint.