Category:Foraminiferal zonation: Difference between revisions
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In the following account Biomarkers in the offshore UK Chalk Group are systematically described from youngest (Biomarker 1) to oldest (Biomarker 15). Alternatively, for information about a particulat Biomarker, select it from the summary table (summary correlation of offshore foraminiferal biomarkers and BGS foraminiferal zones). | In the following account Biomarkers in the offshore UK Chalk Group are systematically described from youngest (Biomarker 1) to oldest (Biomarker 15). Alternatively, for information about a particulat Biomarker, select it from the summary table (summary correlation of offshore foraminiferal biomarkers and BGS foraminiferal zones). | ||
[[category:Biostratigraphy of the Chalk Group]] | [[category:Biostratigraphy of the Chalk Group | ]] |
Revision as of 15:41, 26 September 2013
STAGE | STANDARD ZONE | STANDARD SUBZONE | BGS foraminiferal biozone | |||
Northern England | East Anglia | Northern England | ||||
DANIAN | ||||||
MAASTRICHTIAN | B. casimirovensis | 27 | ||||
B. junior | 26 | |||||
B. occidentalis | ||||||
25 | ||||||
B. lanceolata s.l. | 24 | |||||
CAMPANIAN | B. mucronata s.l. | 23 | ||||
22 | ||||||
21 | ||||||
G. quadrata | I. lingua | Gonioteuthis Zone | Post A. cretaceus | 20 | ||
A. cretaceus | ||||||
Hagenowia horizon | ||||||
O. pilula | Abundant O. pilula ? ? | ?D. binodosus | 19 | |||
E. depressula | ||||||
U. anglicus | 18 | |||||
SANTONIAN | M. testudinarius | |||||
U. socialis | ||||||
M. coranguinum | Upper H. rostrata | 17 | ||||
16 | ||||||
CONIACIAN | Lower H. rostrata | |||||
15 | ||||||
14 | ||||||
M. cortestudinarium | 13 | |||||
TURONIAN | S. plana | 12 | ||||
T. lata | 11 | |||||
10 | ||||||
Mytiloides spp. | ||||||
9 | ||||||
CENOMANIAN | N. juddii | S. gracile | 8 | |||
M. geslinianum | ||||||
7 | ||||||
C. guerangeri | H. trecensis | 6 | ||||
A. jukesbrownei | H. subglobosus | 5 | ||||
4 | ||||||
A. rhotomagense | T. acutus | |||||
T. costatus | ||||||
C. inerme | ||||||
M. dixoni | 3 | |||||
2 | ||||||
M. mantelli | M. saxbii | 1 | ||||
S. schluteri | ||||||
N. carcitanense |
The foraminifera of the Chalk Group in the North Sea Basin were outlined by Wilkinson et al. (1993, 1994). The biomarkers were selected for borehole samples collected by open-hole methods and those chosen were well known, easily identified and based on those commonly used by industry. Definitions were based on the first down-hole occurrences (i.e. extinctions) and a pragmatic approach was taken; a refined or detailed biostratigraphical subdivision of the Chalk Group was not attempted. As the biomarkers offshore were based on 'tops', they do not fit exactly with the onshore biozonation outlined by Wilkinson (2000), which was based on inceptions, extinction and acmes (biomarkers or bioevents within the zones were also recognised). Nevertheless, the biomarkers of the North Sea succession can be related to the onshore biozones, and the purpose of this report is to relate the two schemes.
The biomarkers identified for offshore sequences were, by necessity, defined from the top down. Each biomarker represents a single event and no attempt was made to place them into a zonal scheme. The biomarkers of the Chalk Group in the North Sea Basin are placed, herein, within the context of the biozones recognised in southern and eastern England.
Descriptions of offshore foraminiferal biomarkers in the Chalk Group
The foraminifera biomarkers recognised in the Upper Cretaceous Shetland Group are not included in this synthesis. Being based on First Downhole Occurrences (FDOs), the highest possible stratigraphical positions for the Biomarkers are given here. However, in some cases, similar faunas may be found lower compared to the foraminiferal zones. Distributions are related to the species ranges of southern and eastern England.
In the following account Biomarkers in the offshore UK Chalk Group are systematically described from youngest (Biomarker 1) to oldest (Biomarker 15). Alternatively, for information about a particulat Biomarker, select it from the summary table (summary correlation of offshore foraminiferal biomarkers and BGS foraminiferal zones).
Subcategories
This category has only the following subcategory.
The number of included categories (C), pages (P) and files (F) is stated in brackets.
Pages in category "Foraminiferal zonation"
The following 27 pages are in this category, out of 27 total.
- BGS Zone 1 (=UKB1 and 2 of Hart et al., 1989)
- BGS Zone 2 (UKB3 of Hart et al., 1989)
- BGS Zone 3 (=UKB4 of Hart et al., 1989)
- BGS Zone 4 (=UKB 5 of Hart et al., 1989)
- BGS Zone 5 (=UKB6 of Hart et al., 1989)
- BGS Zone 6 (=modified UKB7 of Hart et al., 1989)
- BGS Zone 7 (=lower UKB 8 of Hart et al., 1989)
- BGS Zone 8 (=upper UKB8 and basal UKB9 of Hart et al., 1989)
- BGS Zone 9 (=modified UKB9 of Hart et al., 1989)
- BGS Zone 10 (=basal UKB10 of Hart et al., 1989)
- BGS Zone 11 (=lower and middle UKB10 of Hart et al., 1989)
- BGS Zone 12 (=upper UKB10 of Hart et al., 1989)
- BGS Zone 13 (=UKB11 of Hart et al., 1989)
- BGS Zone 14 (=lower and middle UKB12 of Hart et al., 1989)
- BGS Zone 15 (=upper UKB12 of Hart et al., 1989)
- BGS Zone 16 (=UKB13 of Hart et al., 1989)
- BGS Zone 17 (=lower and middle UKB14 of Hart et al., 1989)
- BGS Zone 18 (=uppermost UKB14 and lower UKB15 of Hart et al., 1989)
- BGS Zone 19 (=upper UKB15 of Hart et al., 1989)
- BGS Zone 20 (=UKB16 of Hart et al., 1989)
- BGS Zone 21 (=UKB17 and lower UKB 18 of Hart et al., 1989)
- BGS Zone 22 (=uppermost UKB18 of Hart et al., 1989)
- BGS Zone 23 (=UKB19 of Hart et al., 1989)
- BGS Zone 24 (=UKB20 of Hart et al., 1989)
- BGS Zone 25 (=UKB21 of Hart et al., 1989)
- BGS Zone 26(=UKB22 of Hart et al., 1989)
- BGS Zone 27