Where: Antarctica (64.0° S, 57.4° W: paleocoordinates 61.9° S, 68.1° W)
• coordinate estimated from map
• local area-level geographic resolution
When: Marambio Group, Late/Upper Campanian (83.5 - 70.6 Ma)
• Marambio Group sediments of Humps Island (Santa Marta and López de Bertodano formations)
• formation-level stratigraphic resolution
Environment/lithology: marine; lithified, massive, sandy sandstone and lithified, muddy mudstone
•
•Interval 1 (DJ.288.1-7) appears to represent nearshore conditions, the high proportion of spores and pollen (22-36% of total palynomorphs) supporting this suggestion.
•
•Interval 2 (DJ.288.9-13) represents shallow palaeoenvironments. The acanthomorph acritarch Michrystridium spp. increases to a peak abundance (26% of total palynomorphs) in sample DJ.288.11. This genus is indicative of relatively shallow conditions close to a palaeocoastline (Wall 1965). In the same sample, the proportions of Phelodinium exilicornutum and Senoniasphuera spp. (10% and 17% of total palynomorphs respectively) also increase to their maximum abundance.
•
•Interval 3 (DJ.288.14 & 15) represents a change to a more distal palaeoenvironment.
•of the section is predominantly mudstone (Facies C of Pirrie & Riding 1988). The boundary between the Herbert Sound Member and the Cape Lamb Member is seen at the top of the lower portion of mixed sandstone and mudstone, c. 35 m above the base of the section described by Pirrie & Riding (1988). The same lithological change exists 35-50 m above the base of the present section.
Size class: microfossils
• Other: Palynomorphs
Preservation: soft parts, original sporopollenin
Collection methods: bulk, chemical, hydrochloric, hydroflouric,
• University of Sheffield: Repository
Primary reference: P. J. D. Dolding. 1992. Palynology of the Marambio Group (Upper Cretaceous) of northern Humps Island. Antartic Science 4(3):311-326 [C. Jaramillo/P. Santamarina]more details
Purpose of describing collection: biostratigraphic analysis
PaleoDB collection 150182: authorized by Carlos Jaramillo, entered by Patricio Santamarina on 03.09.2013, edited by Bethany Allen
Creative Commons license: CC BY (attribution)
Taxonomic list