Stratigraphy and depositional environments of the Woo Dale Limestones Formation (Dinantian), Derbyshire

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Abstract
SUMMARY: The Woo Dale Limestones Formation is the oldest of the exposed shelf limestone units on the Derbyshire Block. It occurs in four inliers: Peak Forest, Wye Valley, Hartington and Alstonfield. Three members are recognised; the lowest, the Vincent House Member, is present throughout the area and consists of packstones and grainstones with a diverse bioclast assemblage. It represents deposition in a shallow open shelf environment. The Topley Pike Member comprises principally mudstones and wackestones with a restricted fauna. Fenstrate fabrics, desiccation cracks and pseudoanticlines indicate deposition and early diagenesis in a tidal flat environment. The uppermost member, the Dam Dale Member consists of dark-coloured packstones and grainstones with a bioclast assemblage intermediate in diversity between the Topley Pike and Vincent House Members. It represents deposition in a partially restricted lagoon. Tidal flat deposits occur higher in the sequence to the south (Wye Valley, Hartington) than in the north (Peak Forest). This is thought to indicate that tidal flats migrated roughly southwards with time as a result of progradation. The contact of the Woo Dale Limestones with the overlying Bee Low Limestones appears conformable at Peak Forest but unconformable at Wye Valley and Hartington. The relationship at Alstonfield is uncertain.