Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon

Christopher Fuanya; Boniface Kankeu; Anthony Temidayo Bolarinwa; Rose Fouateu Yongue

doi:doi:10.11648/j.aas.20230801.13

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Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon

Christopher Fuanya, Boniface Kankeu, Anthony Temidayo Bolarinwa, Rose Fouateu Yongue

Published in Advances in Applied Sciences (Volume 8, Issue 1)

Received: 14 January 2023 Accepted: 31 January 2023 Published: 14 February 2023

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Abstract

The Ako’ozam–Njabilobe area, which is part of the Nyong group, is characterized mainly by highly deformed gneisses that host amphibolites, and metadolerites as enclaves. The gneisses within the Ako’ozam-Njabilobe area were investigated to constrain their geotectonic environment as well as understand their geodynamic evolution within the Nyong group. Three litho-types of gneisses outcrop within the Ako’ozam-Njabilobe area, consisting of horblende-biotite, quartzofeldspathic, and garnet gneisses. They are strongly peraluminous, with low Yb_N, Rb/Sr, K₂O/Na₂O, and enriched in large ion lithophile elements (LILE). The gneisses within the Ako’ozam-Njabilobe area have a trachy-andesite parentage. The negative anomalies in high field strength elements (HFSE) and enrichments in LILE and light rare earth elements (LREE) suggest a subduction setting for this magmatism. The geochemical signatures including, low K₂O/Na₂O ratio, silica content (67.18 to 73.65 wt%), Yb and Y contents less than 1 and 10 ppm respectively, and low heavy REE values of the studied gneisses are akin to chemical signatures of archean crustal rocks. The Nb/Th < 1 and Th/Yb >1 of the studied gneisses indicate that the magma that sourced their protolith is mantle-derived with some degree of crustal contamination. The similarity in whole rock data of the three lithotypes of gneisses within the Ako’ozam-Njabilobe area suggests a possible mechanical mixing during emplacement. The chemistry of the gneisses indicates a possible Archean inheritance during the emplacement of their protoliths, as such could provide insights into the petrogenetic processes controlling crustal growth and aid in understanding the Archean-Proterozoic transition within the Nyong group.

Published in	Advances in Applied Sciences (Volume 8, Issue 1)
DOI	10.11648/j.aas.20230801.13
Page(s)	15-27
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2023. Published by Science Publishing Group

Keywords

Gneiss, Ako’ozam, Njabilobe, Nyong Group, Paleoproterozoic

References

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Christopher Fuanya, Boniface Kankeu, Anthony Temidayo Bolarinwa, Rose Fouateu Yongue. (2023). Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Advances in Applied Sciences, 8(1), 15-27. https://doi.org/10.11648/j.aas.20230801.13

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Christopher Fuanya; Boniface Kankeu; Anthony Temidayo Bolarinwa; Rose Fouateu Yongue. Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Adv. Appl. Sci. 2023, 8(1), 15-27. doi: 10.11648/j.aas.20230801.13

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Christopher Fuanya, Boniface Kankeu, Anthony Temidayo Bolarinwa, Rose Fouateu Yongue. Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Adv Appl Sci. 2023;8(1):15-27. doi: 10.11648/j.aas.20230801.13

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@article{10.11648/j.aas.20230801.13,
  author = {Christopher Fuanya and Boniface Kankeu and Anthony Temidayo Bolarinwa and Rose Fouateu Yongue},
  title = {Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon},
  journal = {Advances in Applied Sciences},
  volume = {8},
  number = {1},
  pages = {15-27},
  doi = {10.11648/j.aas.20230801.13},
  url = {https://doi.org/10.11648/j.aas.20230801.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.aas.20230801.13},
  abstract = {The Ako’ozam–Njabilobe area, which is part of the Nyong group, is characterized mainly by highly deformed gneisses that host amphibolites, and metadolerites as enclaves. The gneisses within the Ako’ozam-Njabilobe area were investigated to constrain their geotectonic environment as well as understand their geodynamic evolution within the Nyong group. Three litho-types of gneisses outcrop within the Ako’ozam-Njabilobe area, consisting of horblende-biotite, quartzofeldspathic, and garnet gneisses. They are strongly peraluminous, with low YbN, Rb/Sr, K2O/Na2O, and enriched in large ion lithophile elements (LILE). The gneisses within the Ako’ozam-Njabilobe area have a trachy-andesite parentage. The negative anomalies in high field strength elements (HFSE) and enrichments in LILE and light rare earth elements (LREE) suggest a subduction setting for this magmatism. The geochemical signatures including, low K2O/Na2O ratio, silica content (67.18 to 73.65 wt%), Yb and Y contents less than 1 and 10 ppm respectively, and low heavy REE values of the studied gneisses are akin to chemical signatures of archean crustal rocks. The Nb/Th 1 of the studied gneisses indicate that the magma that sourced their protolith is mantle-derived with some degree of crustal contamination. The similarity in whole rock data of the three lithotypes of gneisses within the Ako’ozam-Njabilobe area suggests a possible mechanical mixing during emplacement. The chemistry of the gneisses indicates a possible Archean inheritance during the emplacement of their protoliths, as such could provide insights into the petrogenetic processes controlling crustal growth and aid in understanding the Archean-Proterozoic transition within the Nyong group.},
 year = {2023}
}

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TY  - JOUR
T1  - Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon
AU  - Christopher Fuanya
AU  - Boniface Kankeu
AU  - Anthony Temidayo Bolarinwa
AU  - Rose Fouateu Yongue
Y1  - 2023/02/14
PY  - 2023
N1  - https://doi.org/10.11648/j.aas.20230801.13
DO  - 10.11648/j.aas.20230801.13
T2  - Advances in Applied Sciences
JF  - Advances in Applied Sciences
JO  - Advances in Applied Sciences
SP  - 15
EP  - 27
PB  - Science Publishing Group
SN  - 2575-1514
UR  - https://doi.org/10.11648/j.aas.20230801.13
AB  - The Ako’ozam–Njabilobe area, which is part of the Nyong group, is characterized mainly by highly deformed gneisses that host amphibolites, and metadolerites as enclaves. The gneisses within the Ako’ozam-Njabilobe area were investigated to constrain their geotectonic environment as well as understand their geodynamic evolution within the Nyong group. Three litho-types of gneisses outcrop within the Ako’ozam-Njabilobe area, consisting of horblende-biotite, quartzofeldspathic, and garnet gneisses. They are strongly peraluminous, with low YbN, Rb/Sr, K2O/Na2O, and enriched in large ion lithophile elements (LILE). The gneisses within the Ako’ozam-Njabilobe area have a trachy-andesite parentage. The negative anomalies in high field strength elements (HFSE) and enrichments in LILE and light rare earth elements (LREE) suggest a subduction setting for this magmatism. The geochemical signatures including, low K2O/Na2O ratio, silica content (67.18 to 73.65 wt%), Yb and Y contents less than 1 and 10 ppm respectively, and low heavy REE values of the studied gneisses are akin to chemical signatures of archean crustal rocks. The Nb/Th 1 of the studied gneisses indicate that the magma that sourced their protolith is mantle-derived with some degree of crustal contamination. The similarity in whole rock data of the three lithotypes of gneisses within the Ako’ozam-Njabilobe area suggests a possible mechanical mixing during emplacement. The chemistry of the gneisses indicates a possible Archean inheritance during the emplacement of their protoliths, as such could provide insights into the petrogenetic processes controlling crustal growth and aid in understanding the Archean-Proterozoic transition within the Nyong group.
VL  - 8
IS  - 1
ER  -

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Author Information

Christopher Fuanya

Department of Geology, University of Buea, Buea, Cameroon
Boniface Kankeu

Institute for Geological and Mining Research (IRGM), Yaounde, Cameroon
Anthony Temidayo Bolarinwa

Department of Geology, Pan African University Life and Earth Science Institute (PAULESI), University of Ibadan, Ibadan, Nigeria
Rose Fouateu Yongue

Department of Earth Sciences, University of Yaounde I, Yaounde, Cameroon

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Christopher Fuanya, Boniface Kankeu, Anthony Temidayo Bolarinwa, Rose Fouateu Yongue. (2023). Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Advances in Applied Sciences, 8(1), 15-27. https://doi.org/10.11648/j.aas.20230801.13

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Christopher Fuanya; Boniface Kankeu; Anthony Temidayo Bolarinwa; Rose Fouateu Yongue. Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Adv. Appl. Sci. 2023, 8(1), 15-27. doi: 10.11648/j.aas.20230801.13

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Christopher Fuanya, Boniface Kankeu, Anthony Temidayo Bolarinwa, Rose Fouateu Yongue. Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon. Adv Appl Sci. 2023;8(1):15-27. doi: 10.11648/j.aas.20230801.13

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@article{10.11648/j.aas.20230801.13,
  author = {Christopher Fuanya and Boniface Kankeu and Anthony Temidayo Bolarinwa and Rose Fouateu Yongue},
  title = {Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon},
  journal = {Advances in Applied Sciences},
  volume = {8},
  number = {1},
  pages = {15-27},
  doi = {10.11648/j.aas.20230801.13},
  url = {https://doi.org/10.11648/j.aas.20230801.13},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.aas.20230801.13},
  abstract = {The Ako’ozam–Njabilobe area, which is part of the Nyong group, is characterized mainly by highly deformed gneisses that host amphibolites, and metadolerites as enclaves. The gneisses within the Ako’ozam-Njabilobe area were investigated to constrain their geotectonic environment as well as understand their geodynamic evolution within the Nyong group. Three litho-types of gneisses outcrop within the Ako’ozam-Njabilobe area, consisting of horblende-biotite, quartzofeldspathic, and garnet gneisses. They are strongly peraluminous, with low YbN, Rb/Sr, K2O/Na2O, and enriched in large ion lithophile elements (LILE). The gneisses within the Ako’ozam-Njabilobe area have a trachy-andesite parentage. The negative anomalies in high field strength elements (HFSE) and enrichments in LILE and light rare earth elements (LREE) suggest a subduction setting for this magmatism. The geochemical signatures including, low K2O/Na2O ratio, silica content (67.18 to 73.65 wt%), Yb and Y contents less than 1 and 10 ppm respectively, and low heavy REE values of the studied gneisses are akin to chemical signatures of archean crustal rocks. The Nb/Th 1 of the studied gneisses indicate that the magma that sourced their protolith is mantle-derived with some degree of crustal contamination. The similarity in whole rock data of the three lithotypes of gneisses within the Ako’ozam-Njabilobe area suggests a possible mechanical mixing during emplacement. The chemistry of the gneisses indicates a possible Archean inheritance during the emplacement of their protoliths, as such could provide insights into the petrogenetic processes controlling crustal growth and aid in understanding the Archean-Proterozoic transition within the Nyong group.},
 year = {2023}
}

Copy | Download

TY  - JOUR
T1  - Whole Rock Geochemistry and Geodynamic Evolution of Paleoproterozoic Gneisses, Ako’ozam-Njabilobe Area, Southwestern Cameroon
AU  - Christopher Fuanya
AU  - Boniface Kankeu
AU  - Anthony Temidayo Bolarinwa
AU  - Rose Fouateu Yongue
Y1  - 2023/02/14
PY  - 2023
N1  - https://doi.org/10.11648/j.aas.20230801.13
DO  - 10.11648/j.aas.20230801.13
T2  - Advances in Applied Sciences
JF  - Advances in Applied Sciences
JO  - Advances in Applied Sciences
SP  - 15
EP  - 27
PB  - Science Publishing Group
SN  - 2575-1514
UR  - https://doi.org/10.11648/j.aas.20230801.13
AB  - The Ako’ozam–Njabilobe area, which is part of the Nyong group, is characterized mainly by highly deformed gneisses that host amphibolites, and metadolerites as enclaves. The gneisses within the Ako’ozam-Njabilobe area were investigated to constrain their geotectonic environment as well as understand their geodynamic evolution within the Nyong group. Three litho-types of gneisses outcrop within the Ako’ozam-Njabilobe area, consisting of horblende-biotite, quartzofeldspathic, and garnet gneisses. They are strongly peraluminous, with low YbN, Rb/Sr, K2O/Na2O, and enriched in large ion lithophile elements (LILE). The gneisses within the Ako’ozam-Njabilobe area have a trachy-andesite parentage. The negative anomalies in high field strength elements (HFSE) and enrichments in LILE and light rare earth elements (LREE) suggest a subduction setting for this magmatism. The geochemical signatures including, low K2O/Na2O ratio, silica content (67.18 to 73.65 wt%), Yb and Y contents less than 1 and 10 ppm respectively, and low heavy REE values of the studied gneisses are akin to chemical signatures of archean crustal rocks. The Nb/Th 1 of the studied gneisses indicate that the magma that sourced their protolith is mantle-derived with some degree of crustal contamination. The similarity in whole rock data of the three lithotypes of gneisses within the Ako’ozam-Njabilobe area suggests a possible mechanical mixing during emplacement. The chemistry of the gneisses indicates a possible Archean inheritance during the emplacement of their protoliths, as such could provide insights into the petrogenetic processes controlling crustal growth and aid in understanding the Archean-Proterozoic transition within the Nyong group.
VL  - 8
IS  - 1
ER  -

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