It is composed by 225 meters of thick layers of sandy marlstones
and sandstones intercalations (with cross-bedding) and containing glauconite, which is the cause of the green colour of marlstones
2) dolomitic marlstones
(25% < IR < 50%)--29 samples;
On the basis of the identification of bentonites, we assume that the deep-sea marlstone
in the Ohesaare section correlates with the shallow-water Rumba Formation.
To the east of that region, the main part of the Oandu Stage consists of various marlstone
and argillaceous limestone comprising the Hirmuse Formation (Fig.
It starts with pelagic (above CCD) nannofossil limestones, marlstones
and siltstones, followed by turbiditic sand and siltstones slumped beds or debris flows (e.
A total of 30 samples, including 19 oil shale and 9 marlstone
samples and 2 samples of gastropod fossil remains present in the oil shale seams, were collected from the Changshe Mountain oil shale zone.
The Ninase Member contains fragments of brachiopods and crinoids, and also some tabulate corals (favositids) in the layers of marlstone
intercalating with grainstone.
The Dingqinghu Formation discussed herein mainly consists of dark mudstone, marlstone
, oil shale, siltstone and shale, and contains ostracods and green algae identified in exploration wells .
Ninety-two samples of dolostone and dolomitic marlstone
containing MgO > 10% (classified after Vingisaar et al.
The Pirgu Stage starts with 18 m thick red-coloured dolomitic marlstone
of the Jonstorp Formation.
Interbeds of dolomitic marlstone
, dolostone, and claystone occur in its topmost part.
Oil shale waste rock (limestone, marlstone
or dolostone) is produced during extraction as reject material from separation plant and material from crushing and sizing operations in aggregate production.