Comparisons in depositional style of “polar” and “temperate” glacial ice; Late Paleozoic Whiteout Conglomerate (West Antarctica) and late Proterozoic Mineral Fork Formation (Utah)

Glaciomarine sequence stratigraphy in the Mississippian Río Blanco Basin, Argentina, southwestern Gondwana. Basin analysis and palaeoclimatic implications for the Late Paleozoic Ice Age during the Tournaisian.

Journal of the Geological Society ◽

10.1144/jgs2019-214 ◽

2020 ◽

Vol 177 (6) ◽

pp. 1107-1128 ◽

Cited By ~ 2

Author(s):

Miguel Ezpeleta ◽

Juan José Rustán ◽

Diego Balseiro ◽

Federico Miguel Dávila ◽

Juan Andrés Dahlquist ◽

...

Keyword(s):

Compositional Analysis ◽

Ice Age ◽

Late Paleozoic ◽

Provenance Analysis ◽

Glacial Ice ◽

Content Type ◽

Late Paleozoic Ice Age ◽

Glacial Stage ◽

Supplementary Material ◽

Age Constraints

The Late Paleozoic Ice Age (LPIA) has been well recorded in the uppermost Mississippian–Pennsylvanian of Gondwana. Nevertheless, little is known about the temporal and geographic dynamics, particularly during the early Mississippian. We report on exceptional Tournaisian glaciomarine stratigraphic sections from central Argentina (Río Blanco Basin). Encompassing c. 1400 m, these successions contain conspicuous glacigenic strata with age constraints provided by palaeontological data and U/Pb detrital zircon age spectra. A variety of marine, glaciomarine and fan-deltaic environments indicate relative sea-level variations mainly associated with tectonism and repetitive cycles of glacial activity. Provenance analysis indicates a source from the Sierras Pampeanas basement located to the east. Fifteen sequences were grouped into three depositional models: (1) Transgressive Systems Tracts (TST) to Highstand Systems Tracts (HST) sequences unaffected by glacial ice; (2) Lowstand Systems Tracts (LST) to TST and then to HST with glacial inﬂuence; and (3) non-glacial Falling-Stage Systems Tracts (FSST) to TST and HST. The glacial evidence indicates that the oldest Mississippian glacial stage of the LPIA in southwestern Gondwana is constrained to the middle Tournaisian. In contrast with previous descriptions of Gondwanan coeval glacial records, our sequence analysis confirms complex hierarchical climate variability, rather than a single episode of ice advance and retreat.Supplementary material: Detailed stratigraphic sections, palaeocurrents and compositional analysis and U/Pb detrital Zr methodology and data are available at: https://doi.org/10.6084/m9.figshare.c.5011424

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U-Pb isotopic and geologic evidence for late Paleozoic anatexis, deformation, and accretion of the late Proterozoic Avalon Terrane, southcentral Connecticut

American Journal of Science ◽

10.2475/ajs.287.2.107 ◽

1987 ◽

Vol 287 (2) ◽

pp. 107-126 ◽

Cited By ~ 21

Author(s):

R. P. Wintsch ◽

J. N. Aleinikoff

Keyword(s):

Late Paleozoic ◽

Late Proterozoic

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Paleosols in the transantarctic mountains: indicators of environmental change

Solid Earth Discussions ◽

10.5194/sed-5-1007-2013 ◽

2013 ◽

Vol 5 (2) ◽

pp. 1007-1029 ◽

Cited By ~ 3

Author(s):

J. G. Bockheim

Keyword(s):

Volcanic Ash ◽

Late Quaternary ◽

Dry Valleys ◽

Buried Soils ◽

West Antarctica ◽

Glacial Ice ◽

Last Glaciation ◽

History Of ◽

Climatic History ◽

Transantarctic Mountains

Abstract. The Transantarctic Mountains (TAMs), a 3500 km long chain that subdivides East Antarctica from West Antarctica, are important for reconstructing the tectonic, glacial, and climatic history of Antarctica. With an ice-free area of 24 200 km2 (50% of the total in Antarctica), the TAMs contain an unusually high proportion of paleosols, including relict and buried soils. The unconsolidated paleosols range from late Quaternary to Miocene in age, the semi-consolidated paleosols are of early Miocene to Oligocene age, and the consolidated paleosols are of Paleozoic age. Paleosols on unconsolidated deposits are emphasized in this study. Examples are given from the McMurdo Dry Valleys (78° S) and two outlet glaciers in the central and southern TAMS, including the Hatherton-Darwin Glacier region (80° S) and the Beardmore Glacier region (85° 30' S). Relict soils constitute 73% of all of the soils examined; 10% of the soils featured burials. About 26% of the soils examined are from the last glaciation (< 117 ka) and have not undergone any apparent change in climate. As an example, paleosols comprise 65% of a mapped portion of central Wright Valley. Paleosols in the TAMs feature recycled ventifacts and buried glacial ice in excess of 8 Ma in age; and volcanic ash of Pliocene to Miocene age has buried some soils. Relict soils are more strongly developed than nearby modern soils and often are dry-frozen and feature sand-wedge casts when ice-cemented permafrost was present. The preservation of paleosols in the TAMs can be attributed to cold-based glaciers that are able to override landscapes while causing minimal disturbance.

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Paleosols in the Transantarctic Mountains: indicators of environmental change

Solid Earth ◽

10.5194/se-4-451-2013 ◽

2013 ◽

Vol 4 (2) ◽

pp. 451-459 ◽

Cited By ~ 5

Author(s):

J. G. Bockheim

Keyword(s):

Volcanic Ash ◽

Late Quaternary ◽

Dry Valleys ◽

Buried Soils ◽

West Antarctica ◽

Glacial Ice ◽

Last Glaciation ◽

History Of ◽

Climatic History ◽

Transantarctic Mountains

Abstract. The Transantarctic Mountains (TAMs), a 3500 km long chain that subdivides East Antarctica from West Antarctica, are important for reconstructing the tectonic, glacial, and climatic history of Antarctica. With an ice-free area of 24 200 km2 (50% of the total in Antarctica), the TAMs contain an unusually high proportion of paleosols, including relict and buried soils. The unconsolidated paleosols range from late Quaternary to Miocene in age, the semi-consolidated paleosols are of early Miocene to Oligocene age, and the consolidated paleosols are of Paleozoic age. Paleosols on unconsolidated deposits are emphasized in this study. Examples are given from the McMurdo Dry Valleys (78° S) and two outlet glaciers in the central and southern TAMS, including the Hatherton–Darwin Glacier region (80° S) and the Beardmore Glacier region (85°30' S). Relict soils constitute 73% of all of the soils examined; 10% of the soils featured burials. About 26% of the soils examined are from the last glaciation (< 117 ka) and have not undergone any apparent change in climate. As an example, paleosols comprise 65% of a mapped portion of central Wright Valley. Paleosols in the TAMs feature recycled ventifacts and buried glacial ice in excess of 8 Ma in age, and volcanic ash of Pliocene to Miocene age has buried some soils. Relict soils are more strongly developed than nearby modern soils and often are dry-frozen and feature sand-wedge casts when ice-cemented permafrost is present. The preservation of paleosols in the TAMs can be attributed to cold-based glaciers that are able to override landscapes while causing minimal disturbance.

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