Dbk at 13:12, 26 September 2013

2013-09-26T13:12:27Z

← Older revision		Revision as of 14:12, 26 September 2013
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	'''Bio-markers''': In southern England, the lower part of the zone contains an acme of ''Hagenowia blackmorei'', ''Retispinopora lancingensis'', large ''Isocrania egnabergensis'' and distinctive morphotypes of ''Echinocorys'' (large and small forms of Gaster, 1924) (Mortimore, 1986; Young & Lake, 1988). Medium-sized, rounded ''Echinocorys'' occur at this level in Northern Ireland, and there is an acme of ''Belemnitella'', which is also very locally represented in southern England (Salisbury area) (Bailey ''et al''., 1983; Wilson & Manning, 1978). In the middle of the zone in southern England, bryozoans and the ''Conorca turbinella'' are locally abundant, and occur with ''Cretirhynchia limbata'' sensu Gaster (1924), ''Applinocrinus cretaceus'', ''Cidaris subvesiculosa'' (sensu Gaster, 1924) and ''Offaster pilula nana'' (Gaster, 1924; Young & Lake, 1988). ''A. cretaceus'' also occurs locally at this level in Northern Ireland, together with an acme of ''Orbirhynchia bella'' (Wilson & Manning, 1978). In the upper part of the zone in Northern Ireland there are acmes of ''Galeola papillosa'', depressed forms of ''Echinocorys'', and a further acme of ''Belemnitella'' which is similarly well developed in southern England, where ''Echinocorys'' ''brydonei'' also occurs (Bailey ''et al''., 1983; Wilson & Manning, 1978; Wood, 1995).		'''Bio-markers''': In southern England, the lower part of the zone contains an acme of ''Hagenowia blackmorei'', ''Retispinopora lancingensis'', large ''Isocrania egnabergensis'' and distinctive morphotypes of ''Echinocorys'' (large and small forms of Gaster, 1924) (Mortimore, 1986; Young & Lake, 1988). Medium-sized, rounded ''Echinocorys'' occur at this level in Northern Ireland, and there is an acme of ''Belemnitella'', which is also very locally represented in southern England (Salisbury area) (Bailey ''et al''., 1983; Wilson & Manning, 1978). In the middle of the zone in southern England, bryozoans and the ''Conorca turbinella'' are locally abundant, and occur with ''Cretirhynchia limbata'' sensu Gaster (1924), ''Applinocrinus cretaceus'', ''Cidaris subvesiculosa'' (sensu Gaster, 1924) and ''Offaster pilula nana'' (Gaster, 1924; Young & Lake, 1988). ''A. cretaceus'' also occurs locally at this level in Northern Ireland, together with an acme of ''Orbirhynchia bella'' (Wilson & Manning, 1978). In the upper part of the zone in Northern Ireland there are acmes of ''Galeola papillosa'', depressed forms of ''Echinocorys'', and a further acme of ''Belemnitella'' which is similarly well developed in southern England, where ''Echinocorys'' ''brydonei'' also occurs (Bailey ''et al''., 1983; Wilson & Manning, 1978; Wood, 1995).
	{\| class="~~wikitable" border="1"~~		{\| class="Wikitable
	\| '''Subzones''': \|\| ''Hagenowia ''Horizon		\| '''Subzones''': \|\| ''Hagenowia ''Horizon
	\|-		\|-

Dbk: Created page with "This zone should not be confused with the '''Gonioteuthis'' Zone' of East Anglia, which although similar in name, is conceptually different. In northern England, part of the z..."

2013-09-26T13:12:07Z

Created page with "This zone should not be confused with the '''Gonioteuthis'' Zone' of East Anglia, which although similar in name, is conceptually different. In northern England, part of the z..."

New page

This zone should not be confused with the '''Gonioteuthis'' Zone' of East Anglia, which although similar in name, is conceptually different. In northern England, part of the zone might be represented by the highest part of the exposed succession, but this forms part of the ''Sphenoceramus'' (''Inoceramus'') ''lingua'' Zone (Whitham, 1993).

'''Base''': In southern England, the base of the zone is placed at Telscombe Marl 4 (Mortimore, 1986; Young & Lake, 1988), and in Northern Ireland is coincident with the top of the Creggan Chalk.

'''Top''': In southern England, the top of the zone is placed at the Farlington Marls (Wood, 1995), and in Northern Ireland is coincident with the Whitehead Flint (Wilson & Manning, 1978).

'''Range of index species''': In southern England, the index ranges from within the lower part of the ''O. pilula'' Zone to the top of the nominate zone (Mortimore, 1986). In Northern Ireland, the index species does not appear to range below the base of the zone, and its highest occurrence is at the Whitehead Flint, marking the top of the zone (Wilson & Manning, 1978).

'''Key fauna''':
{| class="Wikitable"
| Porifera: || ''Retispinopora lancingensis''
|-
| Anthozoa: || ''Coelosmilia regularis''
|-
| Annelida: || ''Conorca turbinella''
|-
| Bryozoa: || locally abundant bryozoans
|-
| Brachiopoda: || ''Cretirhynchia intermedia''
|-
| ||'' C. limbata''
|-
| ||''Isocrania egnabergensis'' (large)
|-
| ||''Kingena blackmoorei''
|-
| ||''Orbirhynchia bella''
|-
| Bivalvia: || ''Inoceramus sarumensis''
|-
| ||'' I. subsarumensis''
|-
| Belemnoidea: ||''Belemnitella mucronata''
|-
| ||''Gonioteuthis quadrata''
|-
| Crinoidea: || ''Applinocrinus cretaceus''
|-
| Echinoidea: || ''Cidaris subvesiculosa'' sensu Gaster (1924)
|-
| ||''Echinocorys brydonei''
|-
| ||''E. marginata''
|-
| ||''E.'' sp. (large form of Gaster, 1924)
|-
| ||''E.'' sp. (small form of Gaster, 1924)
|-
| ||''E''. sp. (rounded forms)
|-
| ||''E''. sp. (depressed forms)*
|-
| ||''Galeola papillosa''
|-
| ||''Hagenowia blackmorei''
|-
| ||''Offaster pilula nana''
|}
(*: occurs in the zone in Northern Ireland)

'''Faunal abundance & preservation''': Although the zone has quite a diverse fauna, it is generally sparsely fossiliferous, except at particular horizons of faunal abundance, and many of the fossils are small. The extreme hardness of the Northern Ireland Chalk Group means that many fossils are difficult to collect, and some have been reworked at hardground surfaces.

'''Bio-markers''': In southern England, the lower part of the zone contains an acme of ''Hagenowia blackmorei'', ''Retispinopora lancingensis'', large ''Isocrania egnabergensis'' and distinctive morphotypes of ''Echinocorys'' (large and small forms of Gaster, 1924) (Mortimore, 1986; Young & Lake, 1988). Medium-sized, rounded ''Echinocorys'' occur at this level in Northern Ireland, and there is an acme of ''Belemnitella'', which is also very locally represented in southern England (Salisbury area) (Bailey ''et al''., 1983; Wilson & Manning, 1978). In the middle of the zone in southern England, bryozoans and the ''Conorca turbinella'' are locally abundant, and occur with ''Cretirhynchia limbata'' sensu Gaster (1924), ''Applinocrinus cretaceus'', ''Cidaris subvesiculosa'' (sensu Gaster, 1924) and ''Offaster pilula nana'' (Gaster, 1924; Young & Lake, 1988). ''A. cretaceus'' also occurs locally at this level in Northern Ireland, together with an acme of ''Orbirhynchia bella'' (Wilson & Manning, 1978). In the upper part of the zone in Northern Ireland there are acmes of ''Galeola papillosa'', depressed forms of ''Echinocorys'', and a further acme of ''Belemnitella'' which is similarly well developed in southern England, where ''Echinocorys'' ''brydonei'' also occurs (Bailey ''et al''., 1983; Wilson & Manning, 1978; Wood, 1995).
{| class="wikitable" border="1"
| '''Subzones''': || ''Hagenowia ''Horizon
|-
| ||''Applinocrinus cretaceus'' Subzone
|-
| ||'post ''A. cretaceus'' beds'
|}
'''Age''': Campanian

[[category:Standard zonation | 025]]

Gonioteuthis quadrata Zone - Revision history

Dbk at 13:12, 26 September 2013

Dbk: Created page with "This zone should not be confused with the '''Gonioteuthis'' Zone' of East Anglia, which although similar in name, is conceptually different. In northern England, part of the z..."