Pospichal, James J; Wise, Sherwood W (1990): Abundance of calcareous nannofossils across the K/T boundary at ODP Hole 113-690C (Table 1) [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.746448, Supplement to: Pospichal, JJ; Wise, SW (1990): Calcareous nannofossils across the K/T boundary, ODP Hole 690C, Maud Rise, Weddell Sea. In: Barker, PF, Kennett, JP; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 113, 515-532, https://doi.org/10.2973/odp.proc.sr.113.204.1990
Always quote citation above when using data! You can download the citation in several formats below.
Abstract:
A biostratigraphically continuous, but intensely bioturbated, Cretaceous/Tertiary boundary sequence was cored during Ocean Drilling Program (ODP) Leg 113 on Maud Rise (65°S) in the Weddell Sea off East Antarctica. This interval is the first recovered by ODP/DSDP in the South Atlantic sector of the Southern Ocean and offers a unique opportunity to study the nannofossil sequences leading up to and beyond the terminal Cretaceous event at a high southern latitude.
The K/T boundary lies just within Chron 29R and is placed at ODP Sample 113-690C-15X-4, 41.5 cm. An iridium anomaly was independently noted at about this level as well. Upper Maestrichtian-lower Paleocene sediments consist mostly of light-colored nannofossil chalks. Dark brown sediments at the base of the Danian (Zone CPla) are characterized by an increased clay content attributed to a drop in calcareous microplankton productivity following the terminal Cretaceous event.
Although delineation of the boundary is hampered by intense bioturbation, the sharp color contrast between overlying clay-rich, dark brown chalks of the Tertiary and light cream colored chalks of the Cretaceous aids in the selection of the K/T horizon. Several dark colored burrows sampled at intervals as far as 1.3 m below the boundary and within the light colored Cretaceous chalk were found to contain up to 17% Tertiary nannofossils.
Calcareous nannofossils from the boundary interval were divided into three groups for quantitative study. The three groups, "Cretaceous," "Tertiary," and "Survivor," exhibit a sequential change across the boundary with the Cretaceous forms giving way to a Survivor-dominated assemblage beginning at the boundary followed shortly thereafter by the appearance of the Tertiary taxa, Cruciplacolithus and Hornibrookina. The species, H. edwardsii, comprises nearly 50% of the assemblage just above the Zone CPla/CPlb boundary, an abundance not reported elsewhere at this level. Calculation of individual species abundances reveals several additional differences between this K/T boundary interval and those studied from middle and low latitude sections. The percentage of Thoracosphaera is much lower at the boundary in this section and a small form, Prediscosphaera stoveri, is extremely abundant in Cretaceous sediments just below the boundary.
Project(s):
Ocean Drilling Program (ODP)
Coverage:
Latitude: -65.160000 * Longitude: 1.204800
Date/Time Start: 1987-01-21T07:00:00 * Date/Time End: 1987-01-23T20:30:00
Minimum DEPTH, sediment/rock: 247.080 m * Maximum DEPTH, sediment/rock: 248.850 m
Event(s):
113-690C * Latitude: -65.160000 * Longitude: 1.204800 * Date/Time Start: 1987-01-21T07:00:00 * Date/Time End: 1987-01-23T20:30:00 * Elevation: -2925.0 m * Penetration: 321.2 m * Recovery: 177.19 m * Location: South Atlantic Ocean * Campaign: Leg113 * Basis: Joides Resolution * Method/Device: Drilling/drill rig (DRILL) * Comment: 23 cores; 200.6 m cored; 0 m drilled; 88.3 % recovery
Comment:
<1 = present, but not noted within count of 500 specimens.
Parameter(s):
| # | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
|---|---|---|---|---|---|---|
| 1 | Epoch | Epoch | Pospichal, James J | |||
| 2 | Nannofossil zone | Nannos zone | Pospichal, James J | #1 | ||
| 3 | Nannofossil zone | Nannos zone | Pospichal, James J | #1 | ||
| 4 | Sample code/label | Sample label | Pospichal, James J | DSDP/ODP/IODP sample designation | ||
| 5 | DEPTH, sediment/rock | Depth sed | m | Geocode | ||
| 6 | Biantholithus sparsus | B. sparsus | # | Pospichal, James J | Smear slide analysis | Tertiary |
| 7 | Cruciplacolithus primus | C. primus | # | Pospichal, James J | Smear slide analysis | C. primus/tenuis, Tertiary |
| 8 | Hornibrookina edwardsii | H. edwardsii | # | Pospichal, James J | Smear slide analysis | Tertiary |
| 9 | Biscutum castrorum | B. castrorum | # | Pospichal, James J | Smear slide analysis | Survivors |
| 10 | Cyclagelosphaera reinhardtii | C. reinhardtii | # | Pospichal, James J | Smear slide analysis | Survivors |
| 11 | Lapideacassis sp. | Lapideacassis sp. | # | Pospichal, James J | Smear slide analysis | Survivors |
| 12 | Markalius inversus | M. inversus | # | Pospichal, James J | Smear slide analysis | Survivors |
| 13 | Neocrepidolithus spp. | Neocrepidolithus spp. | # | Pospichal, James J | Smear slide analysis | Survivors |
| 14 | Thoracosphaera spp. | Thoracosphaera spp. | # | Pospichal, James J | Smear slide analysis | Survivors |
| 15 | Zygodiscus sigmoides | Z. sigmoides | # | Pospichal, James J | Smear slide analysis | Survivors |
| 16 | Acuturris scotus | A. scotus | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 17 | Ahmuellerella octoradiata | A. octoradiata | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 18 | Arkhangelskiella spp. | Arkhangelskiella spp. | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 19 | Chiastozygus sp. | Chiastozygus sp. | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 20 | Cretarhabdus conicus | C. conicus | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 21 | Cribrosphaerella daniae | C. daniae | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 22 | Cribrosphaerella ehrenbergii | C. ehrenbergii | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 23 | Eiffellithus turriseiffelii | E. turriseiffelii | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 24 | Gartnerago spp. | Gartnerago spp. | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 25 | Kamptnerius magnificus | K. magnificus | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 26 | Micula decussata | M. decussata | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 27 | Nephrolithus frequens | N. frequens | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 28 | Prediscosphaera cretacea | P. cretacea | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 29 | Prediscosphaera spinosa | P. spinosa | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 30 | Prediscosphaera stoveri | P. stoveri | # | Pospichal, James J | Smear slide analysis | Cretaceous |
| 31 | Nannofossils, tertiary | Nannos tertiary | # | Pospichal, James J | Smear slide analysis | |
| 32 | Nannofossils, survivor | Nannos survivor | # | Pospichal, James J | Smear slide analysis | |
| 33 | Nannofossils, cretaceous | Nannos cretaceous | # | Pospichal, James J | Smear slide analysis | |
| 34 | Nannofossils | Nannos | # | Pospichal, James J | Smear slide analysis |
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
1221 data points