Zonal boundary*
|
Event
|
CK95 GPTS
age (Ma) |
Chron
|
Reference
|
---|---|---|---|---|
P. doliolus/N. reinholdii | LO Nitzschia reinholdii | 0.62 | C1n | Shackleton et al., 1995 |
A/B of N. reinholdii | LO Rhizosolenia praebergonii v. robusta | 1.73 | C1r | Shackleton et al., 1995 |
N. reinholdii/N. marina | FO Fragilariopsis doliolus | 2.00 | C2r.1r | Shackleton et al., 1995 |
A/B of N. marina | LO Thalassiosira convexa s.l. | 2.41 | C2n | Shackleton et al., 1995 |
N. marina/N. jouseae | LO Nitzschia jouseae | 2.77 | C2An.1n | Shackleton et al., 1995 |
N. jouseae/T. convexa | FO Nitzschia jouseae | 5.12 | C3n.4n | Shackleton et al., 1995 |
B/C of T. convexa | LO Thalassiosira miocenica | 5.84 |
|
Shackleton et al., 1995 |
A/B of T. convexa | LO Thalassiosira praeconvexa | 6.18 | C3An.2n | Shackleton et al., 1995 |
T. convexa/N. miocenica | FO Thalassiosira convexa v. aspinosa | 6.57 | C3An.2n | Shackleton et al., 1995 |
A/B of N. miocenica | FO Thalassiosira praeconvexa | 6.71 | C3An.2n | Shackleton et al., 1995 |
N. miocenica/N. porteri | FO Nitzschia miocenica s.l. | 7.30 |
|
Shackleton et al., 1995 |
A/B of N. porteri | LO Thalassiosira burckliana | 7.85 | C4n.2n | Shackleton et al., 1995 |
N. porteri/T. yabei | LO Thalassiosira yabei | 8.23 | C4r.1n | Shackleton et al., 1995 |
A/B of T. yabei | FO Thalassiosira burckliana | 8.91 | C4An | Shackleton et al., 1995 |
T. yabei/A. moronensis | LO Actinocyclus moronensis | 9.76 |
|
Shackleton et al., 1995 |
A. moronensis/C. coscinodiscus | LO Craspedodiscus coscinodiscus | 11.44 |
|
Shackleton et al., 1995 |
C. coscinodiscus/C. gigas v. diorama | LO Actinocyclus ingens | 12.18 |
|
Shackleton et al., 1995 |
C. gigas v. diorama/C. lewisianus | LO Coscinodiscus lewisianus | 12.93 |
|
Shackleton et al., 1995 |
C. lewisianus/C. peplum | LO Cestodiscus peplum | 14.06 | C5ACn | Shackleton et al., 1995 |
A/B of C. peplum | LO Annellus californicus | 14.99 |
|
Shackleton et al., 1995 |
C. peplum/C. nicobarica | FO Cestodiscus peplum | 16.37 | C5Cn.1n | Shackleton et al., 1995 |
A/B of C. nicobarica | LO Thalassiosira burkryi | 16.74 | C5Cr | Barron,1985; Barron, 1992 |
C. nicobarica/T. pileus | FO Crucidenticula nicobarica s.l. | 17.77 |
|
Shackleton et al., 1995 |
T. pileus/C. elegans | LO Craspedodiscus elegans | 18.41 |
|
Barron,1985; Barron, 1992 |
C. elegans/R. paleacea | LO Bogorovia veniamini | 19.59 |
|
Barron,1985; Barron, 1992 |
B/C of R. paleacea | LO Azpeitia oligocenica | 20.27 |
|
Barron,1985; Barron, 1992 |
A/B of R. paleacea | LO Thalassiosira primalabiata | 21.31 |
|
Barron,1985; Barron, 1992 |
R. paleacea/R. gelida | FO Rossiella paleacea | 22.64 |
|
Barron,1985; Barron, 1992 |
R. gelida/B. veniamini | FO Rocella gelida | 24.26 |
|
Barron,1985 |
B. veniamini /R. vigilans | FO Bogorovia veniamini | 25.60 |
|
Barron,1985 |
A/B of R. vigilans | LO Cestodiscus mukhinae | 27.34 |
|
Barron,1985 |
R. vigilans/C. excavatus | LO Coscinodiscus excavatus | 31.91 |
|
Barron,1985 |
bottom of C. excavatus Zone | FO Coscinodiscus excavatus | 34.04 |
|
Barron,1985 |
Notes: * = zonal schemes are based on those of Barron (1985a, 1985b) with modification of Baldauf and Iwai (1995). Bold type = major zonal limits. FO= first occurrence, LO = last occurrence. One exception is the zonal boundary datum of Craspedodiscus coscinodiscus/Coscinodiscus gigas v. diorama zones. We substituted the last common occurrence of Actinocyclus ingens for the FO of Coscinodiscus temperei v. delicata because the species is rare and sporadic. Age values were updated from the literature (Barron, 1985a, 1992; Shackleton et al., 1995) and given in the geomagnetic polarity timescale (GPTS) of Cande and Kent (1995).