The general appearance of the Poiana Rusca Mountains is well-defined in the color of the valley and depressions. From geological point of view, they represent a mosaic in which are found petrography carbonate rocks (limestone Jurassic dolomite coal inf., Limestone conglomerates and a higher level of soft limestone with remains of foraminifera).
The limestone and crystalline structure of these mountains meet large plateaus in the east. On the entire surface of the mountain, the limestone formations do not represent more than 13%. If you take into account the thickness and hardness of large limestone deposits, you will understand that the flow capacity of underground water is wide and the karstification is reduced.
The limestone relief overlaps generally the broad, convex, peaks separated by deep valleys with steep slopes, uplifted by 250-300 m above the river bed. They have impressive gorges, sometimes canyon features: Cerna Valley between Hasdat and Cernii Meadow, Runcu Sohodol Valley, Nandru.
Limestone slopes downstream from Bos Left side of the valley upstream of the town Nandru
Limestone from Seria of Hunedoara
Due to low solubility of the rock, the exokarst is poorly represented by erosion:clints, sinkholes, erosion marmite (more
common in the area Cerbal-Teliuc-Bunila-Sohodol). The endokarst is less developed, but
it has not been made a completeinventory of the caves.Caves are generallysmall and few, a
fact given by the predominance of limestone dolomites. Concretionarycave is poor, being predominantly
the forms of erosion (the marmites upward and
on a side) and corrosion (hieroglyphics).
Hieroglyphics – Peştera Spurcată ( The Polluted Cave) form Nandru Marmite upward – Peştera Spurcată ( The Polluted Cave) form Nandru
The high density of hydrographic network with clear waters and the groundwater near
the surface are explained by thecompactness and impermeability
of the eastern limestones in Poiana Rusca Mountains.
Caves have a great importance historically and archaeologically. C.S.Nicolaescu Plopşor establishes thestratigraphic succession of cave sedimentpolluted from Nandru
in relation to szeletiene and Mousterian pieces. The Postpaleolitic levels inabout two caves fromNandru (Pestera Spurcata si Pestera
Curata) belong to Starcevo-Crisculture, Tiszapolgár, Coţofeni and to the medieval
period.
With the advent of speleological amateur movementof Hunedoara in the east of Poiana Rusca Mountains there were discovered over 50 caves and potholes.Other caves housing
living proof: Cave with water
from Dumbrava, Cave No. 1 from Cerişor, Cave Bulgarelu from Ciulpaz. TheCave of theCauce is representative of appropriate archaeological sediment postpaleolitic stratigraphied .
