Formation age

Type of rocks

Thickness (m)

Main hydraulic characteristics

General consideration


Basalts, scoria, tuff

Up to 700 m

Excellent aquifer

Shallow aquifer connected with all underlying aquifers

Paleocene Eocene

Chalk marls

0 - 40 m

Medium aquifer

Only encountered in some places

Campanian Maastrichtian

Silicified limestone

Around 70 m

Excellent aquifer

Main water aquifer


Marl lenses

0 - 20 m

Lenses of an aquiclude

On very small scale of 100 m aquiclude

Turonian Santonian

Massive sandy limestone

60 m

Excellent aquifer

Excellent karst aquifer


Alternating beds of limestone, dolomite, marly limestone, sandstone, marl and some gypsum layers

Around 300 m

Poorly developed aquifer.

In general, poorly developed aquifer with some good yields layers

Lower Cretaceous

Coarse, medium and coarse-grained sandstone

210 m

Good aquifer

Good to excellent