Simms, M.J., Chidlaw, N., Morton, N. & Page, K.N. 2004. British Lower Jurassic Stratigraphy. Geological Conservation Review Series, No. 30, Joint Nature Conservation Committee, Peterborough, ISBN 1 86 107 495 6.
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Tables
(Table 1.1) Brachiopod biozonal scheme for the Lower Jurassic Series of Great Britain. After Ager (1978, 1990).
Chronostratigraphy |
Brachiopod Biozones |
Ammonite zone equivalents |
Upper Toarcian |
none |
|
Lower Toarcian |
Stolmorhynchia (?) bouchardii Nannirhynchia pygmaea |
Serpentinum–Bifrons Tenuicostatum |
Pliensbachian |
Prionorhynchia serrata Homoeorhynchia acuta Gibbirhynchia curviceps |
Spinatum
Spinatum
Jamesoni–Margaritatus |
Sinemurian |
Cuneirhynchia oxynoti Piarorhynchia juvetzsis |
Semicostatum–Raricostatum Semicostatum |
Hettangian |
Cakirhynchia calcaria |
Planorbis–Bucklandi |
(Table 1.2) Terebratulid stratigraphical distribution in the Lower Jurassic Series of Great Britain. After Ager (1990).
Chronostratigraphy |
Terebratulid Biozones |
Upper Toarcian |
Lobothyris haresfieldensis Zeilleria lycetti |
Lower Toarcian |
Orthotoma globulina |
Upper Pliensbachian |
Zeilleria quadrifida Aulacothyris resupinata Lobothyris punctata |
Lower Pliensbachian |
Cincta numisynalis Zeilleria darwini |
Upper Sinemurian |
Cincta cor |
Lower Sinemurian |
Zeilleria vicinalls |
Hettangian |
Zeilleria perforata |
(Table 2.1) Table of approximate zone/subzone-pair thicknesses for the Hettangian and basal Sinemurian stages at six different locations. (* = figures estimated from total zone thickness.) Data from Cope et al. (1980a), Warrington and lvimey-Cook (1995) and Page (1992, unpublished Geological Society Correlation Guide).
Ammonite zones/ subzone pairs |
Somerset coast |
South Wales (offshore facies) |
Devon–Dorset coast |
Stowell Park Borehole |
Mochras Borehole |
Radstock shelf |
Bucklandi–Lyra |
90 |
? |
4 |
35 |
c. 90* |
0 |
Conybeari–Rotiforme |
47 |
c. 35* |
6 |
18 |
c. 70* |
0 |
Angulata |
40 |
30 |
5 |
17 |
60 |
0 |
Liasicus |
27 |
30 |
/
4 |
18 |
59 |
0.5 |
Planorbis |
8 |
9 |
4 |
11 |
18 |
2.5 |
References