Chalk Group
Lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England.
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Chiltern Hills
Chalk escarpment in England.
The Chiltern Hills are part of a system of chalk downlands throughout eastern and southern England, formed between 65 and 95 million years ago, comprising rocks of the Chalk Group; this also includes Salisbury Plain, Cranborne Chase, the Isle of Wight and the South Downs in the south.
White Cliffs of Dover
Region of English coastline facing the Strait of Dover and France.
British chalk deposits are considered stratigraphically to belong in the Chalk Group.
Chalk
Soft, white, porous, sedimentary carbonate rock.
The Chalk Group is a European stratigraphic unit deposited during the late Cretaceous Period.
Glauconite
Iron potassium phyllosilicate mineral of characteristic green color which is very friable and has very low weathering resistance.
The Glauconitic Marl formation is named after it, and there is a glauconitic sandstone formation in the Mannville Group of Western Canada.
Salisbury Plain
Chalk plateau in the south western part of central southern England covering 300 sqmi.
It is part of a system of chalk downlands throughout eastern and southern England formed by the rocks of the Chalk Group and largely lies within the county of Wiltshire, but stretches into Hampshire.
Alpine orogeny
Orogenic phase in the Late Mesozoic and the current Cenozoic that has formed the mountain ranges of the Alpide belt.
Its effects are particularly visible on the Isle of Wight, where the Chalk Group and overlying Eocene strata are folded to near-vertical, as seen in exposures at Alum Bay and Whitecliff Bay, and on the Dorset coast near Lulworth Cove.
North Downs
The North Downs are a ridge of chalk hills in south east England that stretch from Farnham in Surrey to the White Cliffs of Dover in Kent.
The Chalk Group, composed almost entirely of chalk, a soft, fine-grained limestone. These strata have their origins in the late Cretaceous (approximately 100 – 66 million years ago). For the entirety of this period, south east England was covered by a warm, shallow sea in which coccolithophores, single-celled algae with small calcite skeletons, thrived. As the phytoplankton died, their calcium-rich shells were deposited on the sea bed and, over time were compressed to form rock. The chalk of the North Downs is generally divided into three distinct stata: The Upper Chalk, which has many flints; the Middle Chalk, with fewer flints; and the Lower Chalk or Coombe Rock, greyish, with few flints. The chalk is most commonly exposed on slopes or as cliffs, where the overlying acidic strata have been quarried or washed away. The buried upper surface of the chalk beneath the acidic strata is often eroded into pipes, gulleys and pinnacles, sometimes visible in road cuttings and quarries.
Maastrichtian
The Maastrichtian is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem.
The Maastrichtian was introduced into scientific literature by Belgian geologist André Hubert Dumont in 1849, after studying rock strata of the Chalk Group close to the Dutch city of Maastricht.
Dorset Downs
Area of chalk downland in the centre of the county Dorset in south west England.
The downs are the most western part of a larger chalk formation which also includes (from west to east) Cranborne Chase, Salisbury Plain, Hampshire Downs, Chiltern Hills, North Downs and South Downs.