Stratigraphy of Kyiv: some pictures
Kyiv isn't rich in outcrops of Paleogene deposits. An abandoned quarry in Pyrogiv, though quickly degrading, is one of a few places, where they can be seen.
(~10 m...)
The upper brown layer on the top is Quaternary soil.
The white layer below, according to the literature, was deposited in Miocene epoch. It consists of thin layers of sands, which differ by grain size from invisibly fine to about 2 mm. Thickness of this layer varies greatly from place to place.
The dark brown layer (bottom of the first picture and top of the second) is also Miocenic in age and consists of lignite with carbonaceous clay and thin sand layers. It's thickness is also variable (several to dozen meters).
Greenish-gray sand layer is, seemingly, Oligocenic in age.
The blue clay is decorated with small shiny plates of mica.
When newly exposed, it is especially nice. But later it becomes light brownish-grayish due to oxidation of bivalent iron.
Boundaries: enlarged. Notice the dark hard concretions at the top of blue clays.
This clay is Eocenic in age, probably, Bartonian. It's lying at the top of group of strata which is known as Kyiv suite and was deposited in Lutetian – Bartonian. Deeper parts are more carbonate-rich (marls); the deepest layer consists of sands with phosphorite concretions. Kyiv suite reaches 20 – 30 m in thickness and seems to be the source of majority (or all?) the chondrichthyan teeth which can be found in Kyiv sands.
Uppermost layer of the blue clay contains numerous dark grey concretions and contains some shark teeth (1 piece of a tooth was found in 2 liters of clay), bony fish teeth and vertebrae. Lower layers contain less fossils.
Smaller content of the clay includes large foraminiferans Nodosaria, plenty of microscopic foraminiferans and numerous nannoliths.
Nannoliths from the blue clay – in particular, Discoaster (stars with 4–9 rays) and Chiasmolithus (rings with cross inside). Both these genera are extinct.
According to the usual interpretation, they are scales of unicellular algae from division Haptophyta.