In addition to the coccoliths, the fossil debris includes a variable, but minor, percentage of the fragments of foraminifera, ostracods and mollusks.

The Chalk Group usually shows few signs of bedding, other than lines of flint nodules which become common in the upper part.

Well-known outcrops include the White Cliffs of Dover, Beachy Head, the southern coastal cliffs of the Isle of Wight, Flamborough Head East Yorkshire, the quarries and motorway cuttings at Blue Bell Hill, Kent, (which has been classified as a Site of Special Scientific Interest) and at the Stokenchurch Gap on the Oxfordshire/Buckinghamshire border where the M40 motorway cuts through the Aston Rowant National Nature Reserve.

In the central Chilterns the two parts are separated by the hard Totternhoe Stone, which forms a prominent scarp in some places.

Fossils may be abundant and include the bivalve Spondylus, the brachiopods Terebratulina and Gibbithyris, the echinoids Sternotaxis, Micraster, Echinocorys, and Tylocidaris, the crinoid Marsupites, and the small sponge Porosphaera.

The Chalk outcrops across large parts of southern and eastern England and forms a significant number of the major physiographical features.

Whilst it has been postulated that a chalk cover was laid down across just about all of England and Wales during Cretaceous times, subsequent uplift and erosion has resulted in it remaining only southeast of a line drawn roughly between The Wash and Lyme Bay in Dorset and eastwards from the scarps of the Lincolnshire and Yorkshire Wolds.

For similar reasons, the Chalk is largely absent from the rather smaller area to the south of the Purbeck-Wight Monocline, save for the downs immediately north of Ventnor on the Isle of Wight.

It comprises largely sandstones and mudstones though the Santonian age Gribun Chalk Formation of Mull and nearby Morvern is recognised.

North of the line of the Mid-North Sea - Ringkobing - Fyn structural high, the Chalk Group is still recognisable in drilled samples, but becomes increasingly muddy northwards.

With the exception of some thin sandy units in the inner Moray Firth, this sequence has neither source potential nor reservoir capacity and is not generally considered a drilling target.

However, when these hydrocarbons are produced, diagenesis and compaction can restart which has led to several metres of subsidence at seabed, the collapse of a number of wells, and some extremely expensive remedial work to lift the platforms and re-position them.

[8] Mosasaur remains referred to "Mosasaurus" gracillis from the Turonian aged Chalk Group deposits actually are more closely allied to the Russellosaurina.

[9] A single partial maxillar tooth from Cenomanian aged Chalk Group described as "Iguanodon hilli" belongs to a non-Hadrosaurid Hadrosauroid.