Glossary :: General Geology

Absolute age

An age of a rock or formation given in years determined by radiometric means. See also Relative age.

Aquifer

An aquifer is a layer of porous rock that contains water. See Artisan Well

Artisan Well

An artesian aquifer or well (also known as a confined aquifer) is an aquifer that is trapped between two impermeable layers. An unconfined aquifer is recharged rapidly from surface water. A confined aquifer takes much longer to recharge, but this also mea...More

Cambrian

The earliest defined geological period spanning 550-510Ma. Time before the Cambrian is referred to as the Pre-Cambrian, making the Cambrian the first period of the Paleozoic Era. All fossils are marine from this period and the beginning of this period saw...More

Carboniferous

The fifth period of the Palaeozoic. Spans 353-290Ma, Famous for the extensive coal beds found throughout the UK.Epochs:Stephanian 302-290MaWestphalian 313-302MaNamurian 323-313MaVis�an 341-323MaTournaisian 353-341Ma...More

Clint

A clint or flachkarren is a tabular block of limestone in limestone pavement. See also karst topography and grike....More

Cretaceous

The final period of the Mesozoic. Spans 142-64Ma.

Devonian

The fourth period of the Palaeozoic. Spans 409-353Ma. The rocks of this period are referred to as Old Red Sandstone (ORS) as they are often red coloured sandstone. The name originates from the county of Devon in South West England. The colonisation of lan...More

Eustatic sea level change

Sea level change on a global scale. Causes include the switching between ice age and interglacial periods and changes in the global ocean volume due to plate tectonic movement. Combined with the isostatic changes make a relative sea level change....More

Flachkarren

See clint.

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