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Full-Text Articles in Paleobiology
Fragilariopsis Tigris Sp. Nov., A New Late Pliocene Antarctic Continental Shelf Diatom With Biostratigraphic Promise, Christina R. Riesselman
Fragilariopsis Tigris Sp. Nov., A New Late Pliocene Antarctic Continental Shelf Diatom With Biostratigraphic Promise, Christina R. Riesselman
ANDRILL Research and Publications
Anew species within the genus Fragilariopsis, F. tigris, is described and illustrated using light microscopy and scanning electron microscopy. This species is restricted to a single 8-meter-thick diatom unit within the 585-meter-long section of alternating diatomites and diamictites recovered in the upper portion of the ANtarctic geological DRILLing (ANDRILL) McMurdo Ice Shelf Project (MIS) AND-1B marine sediment core. This new taxon from a diverse, well-preserved diatom assemblage is inferred to be the youngest member of the well-documented, biostratigraphically useful F. praeinterfrigidaria – F. interfrigidaria – F. weaveri lineage and may represent a near-shore corollary to the open-ocean species …
Diatom Evidence For The Onset Of Pliocene Cooling From And-1b, Mcmurdo Sound, Antarctica, Christina R. Riesselman, Robert B. Dunbar
Diatom Evidence For The Onset Of Pliocene Cooling From And-1b, Mcmurdo Sound, Antarctica, Christina R. Riesselman, Robert B. Dunbar
ANDRILL Research and Publications
The late Pliocene, ~3.3–3.0 Ma, is the most recent interval of sustained global warmth in the geologic past. This window is the focus of climate reconstruction efforts by the U.S. Geological Survey’s Pliocene Research, Interpretation, and Synoptic Mapping (PRISM) Data/Model Cooperative, and may provide a useful climate analog for the coming century. Reconstructions of past surface ocean conditions proximal to the Antarctic continent are essential to understanding the sensitivity of the cryosphere to this key interval in Earth’s climate evolution. An exceptional marine sediment core collected from the southwestern Ross Sea (78° S), Antarctica, during ANDRILL’s McMurdo Ice Shelf Project …
A Diatom Record Of Late Pliocene Cooling From The Ross Sea Continental Shelf, And-1b, Antarctica, Charlotte Sjunneskog, Diane Winter
A Diatom Record Of Late Pliocene Cooling From The Ross Sea Continental Shelf, And-1b, Antarctica, Charlotte Sjunneskog, Diane Winter
ANDRILL Research and Publications
A late Pliocene – early Pleistocene, 2.9–2.0Ma, diatom record from the Antarctic Geological Drilling Program (ANDRILL) MIS drillcore AND-1B is presented. This core, recovered from beneath the Ross Ice Shelf south of Ross Island, comprises multiple diatomaceous-sediment units deposited during interglacial periods with open water over the core site. These represent interglacial phases of orbitally paced climate cycles and are punctuated by glacial advances. Extant diatom assemblages have limited presence in the late Pliocene record, which makes environmental interpretation less straight forward. We employ modern ecological data in combination with late Pliocene to present variation in diatom assemblages across the …
Fragilariopsis Diatom Evolution In Pliocene And Pleistocene Antarctic Shelf Sediments, Charlotte Sjunneskog, Christina R. Riesselman, Diane Winter, Reed Scherer
Fragilariopsis Diatom Evolution In Pliocene And Pleistocene Antarctic Shelf Sediments, Charlotte Sjunneskog, Christina R. Riesselman, Diane Winter, Reed Scherer
ANDRILL Research and Publications
The late Pliocene – early Pleistocene sediment record in the AND-1B core from the McMurdo Sound, Ross Sea, Antarctica, displays a rich diversity and high abundance of diatoms, including several new morphologies within the genus Fragilariopsis. These new morphologies exhibit similarities to the extinct late Miocene/early Pliocene species Fragilariopsis aurica Gersonde and Fragilariopsis praecurta Gersonde, as well as to the modern sea ice-associated species Fragilariopsis ritscheri Hustedt and Fragilariopsis obliquecostata van Heurck. From the diverse morphologies present, we use light microscopy and scanning electron microscopy to identify and describe the characteristics of three new taxa, Fragilariopsis laqueata Riesselman, Fragilariopsis …