Hodderense Limestone Formation

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Hodderense Limestone Formation (BOH), Carboniferous, Northern England Province[edit]

Hodderense Limestone Formation is part of the Yoredale Group Since the Bowland Shale Formation extends into onshore southern Great Britain the definition that follows has been unified with that of Waters et al. (2009)[1].

Name[edit]

The formation was first recognised informally as the Beyrichoceras hodderense Bed (Parkinson, 1926[2]). Revision of the eponymous fauna to Bollandoceras hodderense led to a change in the informal name (Earp et al., 1961[3]), which was subsequently revised to the Hodderense Limestone Formation, formally defined by Riley (1990)[4].

Lithology[edit]

Grey sandstone occurs in the Cow Ark Anticline (Wadge et al., 1983[5]). Chert is common in the Isle of Man sections, where some beds are multistorey and display lag horizons composed of reworked micrite nodules, inadunate crinoids, bellerophontid gastropods, cephalopods, trilobites and sponges (Chadwick et al., 2001[6]). Also present is the trace fossil Helminthoides.

Genetic interpretation[edit]

The facies represents a deep-marine hemipelagic carbonate, deposited in a setting that was mainly starved of clastic supply and lay below storm wave base. Helminthoides is a deep-water trace fossil.

Stratotype[edit]

The type section is the east bank of the River Hodder, Great Falls (SD 7035 3999), near Stonyhurst, near Clitheroe, Lancashire. The base and top of the formation are seen in the section (Earp et al., 1961[7]). Reference sections include south of the old lime kilns at the Visitor Centre at Scarlett, Isle of Man (SC 2580 6620) where the base of the formation is seen, and a cliff section at Scarlett Point, Isle of Man (SC 2583 6633) where the top of the formation is seen.

Lower and upper boundaries[edit]

In the Craven Basin the base of the formation is drawn at the base of the first cream-coloured wackestone with dark blue micritic nodules of the Hodderense Limestone Formation, where it rests conformably on grey or dark grey mudstone and calcisiltite of the Hodder Mudstone Formation, Craven Group, of Chadian to Holkerian age.

In the south of the Isle of Man, at the Visitor Centre at Scarlett, south of the old lime kilns, the wackestones and packstones of the underlying Knockrushen Formation are overlain by the massive lime mudstones of the Hodderense Limestone Formation (Figure 8, Column 8). The base of the latter is taken at the lowest mottled horizon (Dickson et al., 1987[8]), and this mottling is a result of the presence of blue or grey micrite nodules up to 3 cm in size.

In the Craven Basin, the top of the formation is drawn at the conformable upward passage from the highest nodule bearing cream-coloured wackestone bed of the Hodderense Limestone Formation, to the first grey mudstone of the Pendleside Limestone Formation, Craven Group, of late Holkerian to Asbian age.

In the south of the Isle of Man, at Scarlett Point (SC 2583 6633), the upper boundary of the Hodderense Limestone Formation occurs below the lowest black claystone of the wackestones, lime-mudstones and interbedded claystones of the Scarlett Point Member, Bowland Shale Formation (Figure 8, Column 8).

Thickness[edit]

Up to 15.m in north-west England and 14 m in the Isle of Man.

Distribution

Craven Basin, north-west England, although removed beneath the unconformity in the Skipton area; south Isle of Man.

Age and biostratigraphical characterisation[edit]

Holkerian. The ammonoid assemblage, including Bollandoceras hodderense, is indicative of the upper part of the Bollandites–Bollandoceras (BB) Zone (Aitkenhead et al., 1992[9]). In the south Isle of Man, Scarlett Quarry (SC 258 662) is the type locality of the ammonoid Merocanites henslowi.

References[edit]

  1. Waters, C N, Waters, R A, Barclay, W J, and Davies, J R.2009.BGS Stratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore).British Geological Survey Research Report, RR/09/01.
  2. Parkinson, D.1926.The faunal succession in the CarboniferousLimestone and Bowland Shales at Clitheroe and Pendle Hill, Lancashire.Quarterly Journal of the Geological Society of London, Vol. 82, 188–249
  3. Earp, J R, Magraw, D, Poole, E G, Land, D H, and Whiteman,A J.1961.Geology of the country around Clitheroe and Nelson.Memoir of the Geological Survey of Great Britain, Sheet 68 (England and Wales)
  4. Riley, N J.1990.Stratigraphy of the Worston Shale Group (Dinantian), Craven Basin, North West England.Proceedings of the Yorkshire Geological Society, Vol. 48, 163–187
  5. Wadge, A J, Bateson, J H, and Evans, A D.1983.Mineral reconnaissance surveys in the Craven Basin.Institute of Geological Sciences Mineral Reconnaissance Programme Report, Vol. 66, 1–100.
  6. Chadwick, R A, Jackson, D I, Barnes, R P, Kimbell, G S, Johnson, H, Chiverrell, R C, Thomas, G S P, Jones, N S, Riley, N J, Pickett, E A, Young, B, Holliday, D W, Ball, D F, Molyneux, S G, Long, D, Power, G M, and Roberts, D H.2001.The geology of the Isle of Man and its offshore area.British Geological Survey Research Report, RR/01/06.
  7. Earp, J R, Magraw, D, Poole, E G, Land, D H, and Whiteman,A J.1961.Geology of the country around Clitheroe and Nelson.Memoir of the Geological Survey of Great Britain, Sheet 68 (England and Wales)
  8. Dickson, J A D, Ford, T D, and Swift, A.1987.The strati-graphy of the Carboniferous rocks around Castletown, Isle of Man.Proceedings of the Yorkshire Geological Society, Vol. 46, 203–229.
  9. Aitkenhead, N, Bridge, D M, Riley, N J, and Kimbell, S F.1992.Geology of the country around Garstang.Memoir of the British Geological Survey, Sheet 67 (England and Wales)