Formation age

Type of rocks

Thickness (m)

Main hydraulic characteristics

General consideration

Neogene to recent

Basalts

Up to a few 100 m

Excellent aquifer

In Central north Jordan

Paleocene Eocene

Chalk marls

0 - 60 m

Medium aquifer

NW of Irbed City and in Azraq and Hammad areas

Maastrichtian Paleocene

Bituminous marl

200 - 300 m

Aquitard, confining layers

Campanian Maastrichtian

Silicified limestone overlain by beds of phosphatic chert

Around 70 m

Excellent aquifer

Main water aquifer

Turonian

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

Cenomanian

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

Around 300 m

Poorly developed aquifer. In many areas springs issue from the limestone and dolomite beds

In general, poorly developed aquifer with some good yields aquifer layers

Lower Cretaceous

Coarse, medium and coarse-grained sandstone

200 m

Good aquifer

Deep aquifer containing brackish water