Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica
Distribution patterns, petrography, whole-rock and mineral chemistry, and shape and fabric data are described for the most representative basement lithologies occurring as clasts (granule to boulder grain-size class) from the 625 m deep CRP-2/2A drillcore. A major change in the distribution pattern...
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ftunivnebraskali:oai:digitalcommons.unl.edu:geosciencefacpub-1140 2023-11-12T04:04:38+01:00 Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica Talarico, F Sandroni, S Fielding, Christopher R. Atkins, C 2000-01-01T08:00:00Z application/pdf https://digitalcommons.unl.edu/geosciencefacpub/139 https://digitalcommons.unl.edu/context/geosciencefacpub/article/1140/viewcontent/Fielding_TA_2000_Variability_petrography.pdf unknown DigitalCommons@University of Nebraska - Lincoln https://digitalcommons.unl.edu/geosciencefacpub/139 https://digitalcommons.unl.edu/context/geosciencefacpub/article/1140/viewcontent/Fielding_TA_2000_Variability_petrography.pdf Papers in the Earth and Atmospheric Sciences Earth Sciences text 2000 ftunivnebraskali 2023-10-30T10:44:25Z Distribution patterns, petrography, whole-rock and mineral chemistry, and shape and fabric data are described for the most representative basement lithologies occurring as clasts (granule to boulder grain-size class) from the 625 m deep CRP-2/2A drillcore. A major change in the distribution pattern of the clast types occurs at c. 310 mbsf, with granitoid-dominated clasts above and mainly dolerite clasts below; moreover, compositional and modal data suggest a further division into seven main detrital assemblages or petrofacies. In spite of this variability, most granitoid pebbles consist of either pink or grey biotite±hornblende monzogranites. Other less common and ubiquitous lithologies include biotite syenogranite, biotite-hornblende granodiorite, tonalite, monzogranitic or monzonitic porphyries (very common below 310 mbsf), microgranite, and subordinately, monzogabbro, Ca-silicate rocks, biotite-clinozoisite schist and biotite orthogneiss (restricted to the pre-Pliocene strata). The ubiquitous occurrence of biotite±hornblende monzogranite pebbles in both the Quaternary-Pliocene and Miocene-Oligocene sections, apparently reflects the dominance of these lithologies in the onshore basement, and particularly in the Cambro-Ordovician Granite Harbour Igneous Complex which forms the most extensive outcrop in southern Victoria Land. The petrographical features of the other CRP-2/2A pebble lithologies are consistent with a supply dominantly from areas of the Transantarctic Mountains facing the CRP-2/2A site, and they thus provide further evidence of a local provenance for the supply of basement clasts to the CRP-2/2A sedimentary strata. Text Antarc* Antarctica Victoria Land University of Nebraska-Lincoln: DigitalCommons@UNL Victoria Land Transantarctic Mountains Granite Harbour ENVELOPE(162.733,162.733,-76.883,-76.883) |
institution |
Open Polar |
collection |
University of Nebraska-Lincoln: DigitalCommons@UNL |
op_collection_id |
ftunivnebraskali |
language |
unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Talarico, F Sandroni, S Fielding, Christopher R. Atkins, C Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
topic_facet |
Earth Sciences |
description |
Distribution patterns, petrography, whole-rock and mineral chemistry, and shape and fabric data are described for the most representative basement lithologies occurring as clasts (granule to boulder grain-size class) from the 625 m deep CRP-2/2A drillcore. A major change in the distribution pattern of the clast types occurs at c. 310 mbsf, with granitoid-dominated clasts above and mainly dolerite clasts below; moreover, compositional and modal data suggest a further division into seven main detrital assemblages or petrofacies. In spite of this variability, most granitoid pebbles consist of either pink or grey biotite±hornblende monzogranites. Other less common and ubiquitous lithologies include biotite syenogranite, biotite-hornblende granodiorite, tonalite, monzogranitic or monzonitic porphyries (very common below 310 mbsf), microgranite, and subordinately, monzogabbro, Ca-silicate rocks, biotite-clinozoisite schist and biotite orthogneiss (restricted to the pre-Pliocene strata). The ubiquitous occurrence of biotite±hornblende monzogranite pebbles in both the Quaternary-Pliocene and Miocene-Oligocene sections, apparently reflects the dominance of these lithologies in the onshore basement, and particularly in the Cambro-Ordovician Granite Harbour Igneous Complex which forms the most extensive outcrop in southern Victoria Land. The petrographical features of the other CRP-2/2A pebble lithologies are consistent with a supply dominantly from areas of the Transantarctic Mountains facing the CRP-2/2A site, and they thus provide further evidence of a local provenance for the supply of basement clasts to the CRP-2/2A sedimentary strata. |
format |
Text |
author |
Talarico, F Sandroni, S Fielding, Christopher R. Atkins, C |
author_facet |
Talarico, F Sandroni, S Fielding, Christopher R. Atkins, C |
author_sort |
Talarico, F |
title |
Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
title_short |
Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
title_full |
Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
title_fullStr |
Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
title_full_unstemmed |
Variability, Petrography and Provenance of Basement Clasts in Core from CRP-2/2A, Victoria Land Basin, Antarctica |
title_sort |
variability, petrography and provenance of basement clasts in core from crp-2/2a, victoria land basin, antarctica |
publisher |
DigitalCommons@University of Nebraska - Lincoln |
publishDate |
2000 |
url |
https://digitalcommons.unl.edu/geosciencefacpub/139 https://digitalcommons.unl.edu/context/geosciencefacpub/article/1140/viewcontent/Fielding_TA_2000_Variability_petrography.pdf |
long_lat |
ENVELOPE(162.733,162.733,-76.883,-76.883) |
geographic |
Victoria Land Transantarctic Mountains Granite Harbour |
geographic_facet |
Victoria Land Transantarctic Mountains Granite Harbour |
genre |
Antarc* Antarctica Victoria Land |
genre_facet |
Antarc* Antarctica Victoria Land |
op_source |
Papers in the Earth and Atmospheric Sciences |
op_relation |
https://digitalcommons.unl.edu/geosciencefacpub/139 https://digitalcommons.unl.edu/context/geosciencefacpub/article/1140/viewcontent/Fielding_TA_2000_Variability_petrography.pdf |
_version_ |
1782341711817605120 |