Lower Cretaceous nannofossils of ODP Holes 113-682B and 113-693A, supplement to: Mutterlose, Jörg; Wise, Sherwood W (1990): Lower Cretaceous nannofossil biostratigraphy of ODP Leg 113 Holes 692B and 693A, continental slope off East Antarctica, 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, 325-351

Organic-rich, moderately to sparsely nannofossiliferous Lower Cretaceous claystones ("black shales") were cored at two Ocean Drilling Program Leg 113 sites on the continental slope of East Antarctica off Dronning Maud Land. A 39 m section at Site 692 yielded a Neocomian assemblage of limit...

Full description

Bibliographic Details
Main Authors: Mutterlose, Jörg, Wise, Sherwood W
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA - Data Publisher for Earth & Environmental Science 1990
Subjects:
Drilling/drill rig
Leg113
Joides Resolution
Ocean Drilling Program ODP
Dronning Maud Land
East Antarctica
Falkland Plateau
Kennett
Weddell
Weddell Sea
Antarc*
Antarctica
Online Access:https://dx.doi.org/10.1594/pangaea.746421
https://doi.pangaea.de/10.1594/PANGAEA.746421
Description
Summary:Organic-rich, moderately to sparsely nannofossiliferous Lower Cretaceous claystones ("black shales") were cored at two Ocean Drilling Program Leg 113 sites on the continental slope of East Antarctica off Dronning Maud Land. A 39 m section at Site 692 yielded a Neocomian assemblage of limited diversity with rare Cyclagelosphaera deflandrei, Diadorhombus rectus, and Cruciellipsis cuvillieri, and is probably Valanginian in age. A 70-m section at Site 693 is assigned to the Rhagodiscus angustus Zone (late Aptian-early Albian in age). The latter zone is represented at DSDP sites on the Falkland Plateau, but equivalents to the Neocomian section are absent there, probably due to a disconformity. Watznaueria barnesae is the dominant species at both ODP sites, but it shares dominance with Repagulum parvidentatum at Site 693, where they total 70%-90% of the assemblage; their dominance is attributed to a paleogeographic setting within a restricted basin rather than to postdepositional dissolution of other species. The evolutionary development of this restricted basin and its eventual ventilation in early Albian times is discussed in terms of the regional stratigraphy and the breakup and dispersal of southwestern Gondwanaland. One new species, Corollithion covingtonii, is described.

Similar Items