Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings
Grain size analysis, geochemistry, and petrography of sandstones of the Ilaro Formation exposed at the Ajegunle area were investigated to infer provenance, transportation history, tectonic setting, paleoenvironment, and degree of palaeoweathering of the sediments. Selected sandstones were analyzed,...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nigerian Society of Physical Sciences
2024-03-01
|
| Series: | Journal of Nigerian Society of Physical Sciences |
| Subjects: | |
| Online Access: | https://journal.nsps.org.ng/index.php/jnsps/article/view/1726 |
| _version_ | 1827318805677735936 |
|---|---|
| author | A. Y. Jimoh M. B. Saadu A. A. Adetoro J. Ajadi T. Issa U. Issa |
| author_facet | A. Y. Jimoh M. B. Saadu A. A. Adetoro J. Ajadi T. Issa U. Issa |
| author_sort | A. Y. Jimoh |
| collection | DOAJ |
| description |
Grain size analysis, geochemistry, and petrography of sandstones of the Ilaro Formation exposed at the Ajegunle area were investigated to infer provenance, transportation history, tectonic setting, paleoenvironment, and degree of palaeoweathering of the sediments. Selected sandstones were analyzed, and the major, trace, and rare earth elements were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results from the granulometric analysis showed that sandstones were deposited in fluvial conditions. The sandstones exhibit a coarse-grained texture, displaying poor sorting and being texturally immature. The petrographic analysis indicated that quartz was predominant, whereas opaque minerals, muscovite, and ferruginous ground mass were present in smaller quantities. The sandstones can be geochemically classified as arkose and subarenite. The sandstones have an average composition of SiO2 (82.87%) and Al2O3 (9.49%), while K2O, Na2O, MgO, CaO, and P2O5 have <1% each. The elevated Al2O3 content is associated with the lithic fragment composition, whereas the low concentrations of MgO (mean 0.03%), Na2O (mean 0.008%), and K2O (mean 0.04%) suggest chemical destruction in an oxidizing environment. The angularity of the grains indicated a short transportation history very close to the provenance. Bivariate and discriminant plots from major elements and trace elements suggest the sandstones were non-marine and sourced from intermediate rocks. The sandstones were deposited in an oxic-dyoxic condition under a humid climate and passive or active continental margins. The average values of the weathering indices indicate an intense degree of chemical weathering.
|
| first_indexed | 2024-03-07T14:09:43Z |
| format | Article |
| id | doaj.art-5ce7e1bdeacc4e08800b9e3aaad4cbcf |
| institution | Directory Open Access Journal |
| issn | 2714-2817 2714-4704 |
| language | English |
| last_indexed | 2024-04-25T00:09:01Z |
| publishDate | 2024-03-01 |
| publisher | Nigerian Society of Physical Sciences |
| record_format | Article |
| series | Journal of Nigerian Society of Physical Sciences |
| spelling | doaj.art-5ce7e1bdeacc4e08800b9e3aaad4cbcf2024-03-13T17:01:46ZengNigerian Society of Physical SciencesJournal of Nigerian Society of Physical Sciences2714-28172714-47042024-03-016110.46481/jnsps.2024.1726Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settingsA. Y. Jimoh0M. B. Saadu1 A. A. Adetoro2J. Ajadi3 T. Issa4U. Issa5Department of Geology and Mineral Science, Faculty of Pure and Applied Sciences, Kwara State UniversityDepartment of Geology and Mineral Science, Faculty of Pure and Applied Sciences, Kwara State UniversityFaculty of Science and Engineering, University of Hull, Hull, United KingdomDepartment of Geology and Mineral Science, Faculty of Pure and Applied Sciences, Kwara State UniversityDepartment of Geology and Mineral Science, Faculty of Pure and Applied Sciences, Kwara State UniversityDepartment of Geology and Mineral Science, Faculty of Pure and Applied Sciences, Kwara State University Grain size analysis, geochemistry, and petrography of sandstones of the Ilaro Formation exposed at the Ajegunle area were investigated to infer provenance, transportation history, tectonic setting, paleoenvironment, and degree of palaeoweathering of the sediments. Selected sandstones were analyzed, and the major, trace, and rare earth elements were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results from the granulometric analysis showed that sandstones were deposited in fluvial conditions. The sandstones exhibit a coarse-grained texture, displaying poor sorting and being texturally immature. The petrographic analysis indicated that quartz was predominant, whereas opaque minerals, muscovite, and ferruginous ground mass were present in smaller quantities. The sandstones can be geochemically classified as arkose and subarenite. The sandstones have an average composition of SiO2 (82.87%) and Al2O3 (9.49%), while K2O, Na2O, MgO, CaO, and P2O5 have <1% each. The elevated Al2O3 content is associated with the lithic fragment composition, whereas the low concentrations of MgO (mean 0.03%), Na2O (mean 0.008%), and K2O (mean 0.04%) suggest chemical destruction in an oxidizing environment. The angularity of the grains indicated a short transportation history very close to the provenance. Bivariate and discriminant plots from major elements and trace elements suggest the sandstones were non-marine and sourced from intermediate rocks. The sandstones were deposited in an oxic-dyoxic condition under a humid climate and passive or active continental margins. The average values of the weathering indices indicate an intense degree of chemical weathering. https://journal.nsps.org.ng/index.php/jnsps/article/view/1726sandstoneTrace elementsPetrographyGeochemical |
| spellingShingle | A. Y. Jimoh M. B. Saadu A. A. Adetoro J. Ajadi T. Issa U. Issa Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings Journal of Nigerian Society of Physical Sciences sandstone Trace elements Petrography Geochemical |
| title | Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings |
| title_full | Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings |
| title_fullStr | Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings |
| title_full_unstemmed | Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings |
| title_short | Sedimentological and geochemical evaluation of sandstones of the Ilaro formation, Dahomey Basin, Southwestern Nigeria : Insights into paleoenvironments, provenance, and tectonic settings |
| title_sort | sedimentological and geochemical evaluation of sandstones of the ilaro formation dahomey basin southwestern nigeria insights into paleoenvironments provenance and tectonic settings |
| topic | sandstone Trace elements Petrography Geochemical |
| url | https://journal.nsps.org.ng/index.php/jnsps/article/view/1726 |
| work_keys_str_mv | AT ayjimoh sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings AT mbsaadu sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings AT aaadetoro sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings AT jajadi sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings AT tissa sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings AT uissa sedimentologicalandgeochemicalevaluationofsandstonesoftheilaroformationdahomeybasinsouthwesternnigeriainsightsintopaleoenvironmentsprovenanceandtectonicsettings |