The information on this page is a summary description. The full formal description is available here: Trivières Chalk Formation Abbreviation TRI Parent unit Chalk group Child units Lithological description A white to greyish marly chalk without flints. A conglomerate, from a few cm to one m thick, generally marks the base containing hardground fragments, phosphatised...
The information on this page is a summary description. The full formal description is available here: Obourg Chalk Formation Abbreviation OBG Parent unit Chalk group Child units Lithological description A fine-grained white chalk, slightly greyer than the overlying Nouvelles Formation. In the northern part of the basin it contains a few dark black flints (used...
The information on this page is a summary description. The full formal description is available here: Nouvelles Chalk Formation Abbreviation NOU Parent unit Chalk group Child units Lithological description A pure, massive, soft, very fine-grained white chalk, without flints, except for two to three bands of small flint nodules at the top. There is a...
The information on this page is a summary description. The full formal description is available here: Spiennes Chalk Formation Abbreviation SPI Parent unit Chalk group Child units Lithological description A white to whitish-grey, rather coarse-grained chalk, which becomes calcarenitic towards the top. It contains many large black to grey-brown cherts and some black chert bands,...
The information on this page is a summary description. The full formal description is available here: Ciply-Malogne Phosphatic Chalk Formation Abbreviation CIP Parent unit Chalk group Child units Lithological description Cohesive or crumbly calcarenite, invariably intensely bioturbated, consisting of phosphate granules within a chalky matrix. The granules are brown at the surface, but grey in...
The information on this page is a summary description. The full formal description is available here: Saint-Symphorien Calcarenite Formation Abbreviation SSY Parent unit Chalk group Child units Lithological description Crumbly, porous, poorly cemented, grey when fresh, yellow to brownish at the altered surface, often bioturbated, calcarenites or calcirudites. Locally the calcarenites may contain grey, green...
The information on this page is a summary description. The full formal description is available here: Aachen Formation Abbreviation AAC Parent unit Chalk group Child units Hergenrath Member, Aachen Member, Hauset Member Lithological description A complex unit, in the type area primarily sands with intercalations of clayey and silty sands and sandy and silty clays...
The information on this page is a summary description. The full formal description is available here: Hergenrath Member Abbreviation Parent unit Aachen Formation Child units Lithological description Alternation of light to dark grey, sandy and silty clays with silty and clayey, light grey fine to coarse-grained sands, with subordinate fine-grained gravel, silts, minor red clays...
The information on this page is a summary description. The full formal description is available here: Aachen Member Abbreviation Parent unit Aachen Formation Child units Lithological description Well-sorted, yellow-white to clean white, limonite-stained fine sands, locally with irregular gravelly sandstone beds and concretions, with small- and large-scale cross-bedding. Flaser cross-bedding occurs commonly; bioturbation of varying...
The information on this page is a summary description. The full formal description is available here: Maisières Chalk Formation Abbreviation MAI Parent unit Chalk group Child units Lithological description Glauconitic, granular, calcarenitic green “chalk”, with erosion surfaces and/or perforated hardgrounds at the base. Becomes more chalky towards the west and is the equivalent of lithological...
