Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach
Marine and eolian carbonate deposits, grouped under the name “Tamala Limestone”, have been investigated along thousands of kilometers of coastal Western Australia (WA). Relative-age diagenetic features of carbonate sand dunes or “eolianites” indicate that coastal ridges decrease in age seaward, refl...
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| Format: | Journal Article |
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Elsevier BV
2008
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S1871101407000477 http://hdl.handle.net/20.500.11937/27920 |
| _version_ | 1848752397368688640 |
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| author | Hearty, P. O'Leary, Mick |
| author_facet | Hearty, P. O'Leary, Mick |
| author_sort | Hearty, P. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Marine and eolian carbonate deposits, grouped under the name “Tamala Limestone”, have been investigated along thousands of kilometers of coastal Western Australia (WA). Relative-age diagenetic features of carbonate sand dunes or “eolianites” indicate that coastal ridges decrease in age seaward, reflecting coastal accretion during successive sea-level stands. Yellow- to red-stained quartz sands are associated with eolianites as pits, lenses, extensive beds, and even 40-m-high dunes.A regional survey using whole-rock and land snail amino acid epimerization geochronology confirms the eolianite succession and provides a means of correlating widespread deposits along a steep climatic gradient and 16° of latitude. AMS 14C and uranium–thorium (U/Th) ages provide independent radiometric calibration of the amino acid ratios, and eolianite ages can be estimated using a parabolic kinetic model.Over 90% of the sampled eolianite deposits comprise Aminozones A, C, E (125 ka), F?, G, and H, and correlate with interglacials from <10 ka (Holocene) to ca. 500 ka. In contrast, at the type locality of the Tamala Limestone along the Zuytdorp Cliffs, the upper eolianite-paleosol units are characterized by advanced stages of cavernous weathering, pedogenesis, and recrystallization. In the same units, sediment and snail samples generally yield very low or non-detectable levels of amino acids. These factors along with the stratigraphic complexity of the deposits reflect an age much greater than a large majority of sites along the WA coastline. These findings encourage a revision of the existing classification and nomenclature of Quaternary carbonate deposits in WA, as well as a reexamination of the underlying mechanisms related to the formation and emplacement of both carbonate and quartz dunes. |
| first_indexed | 2025-11-14T08:07:58Z |
| format | Journal Article |
| id | curtin-20.500.11937-27920 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:07:58Z |
| publishDate | 2008 |
| publisher | Elsevier BV |
| recordtype | eprints |
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| spelling | curtin-20.500.11937-279202017-10-02T02:27:39Z Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach Hearty, P. O'Leary, Mick Quaternary sea-level cycles Eolianite Bothriembryon land snails Amino acid epimerization dating Western Australia Limestone diagenesis Whole-rock Tamala Limestone Marine and eolian carbonate deposits, grouped under the name “Tamala Limestone”, have been investigated along thousands of kilometers of coastal Western Australia (WA). Relative-age diagenetic features of carbonate sand dunes or “eolianites” indicate that coastal ridges decrease in age seaward, reflecting coastal accretion during successive sea-level stands. Yellow- to red-stained quartz sands are associated with eolianites as pits, lenses, extensive beds, and even 40-m-high dunes.A regional survey using whole-rock and land snail amino acid epimerization geochronology confirms the eolianite succession and provides a means of correlating widespread deposits along a steep climatic gradient and 16° of latitude. AMS 14C and uranium–thorium (U/Th) ages provide independent radiometric calibration of the amino acid ratios, and eolianite ages can be estimated using a parabolic kinetic model.Over 90% of the sampled eolianite deposits comprise Aminozones A, C, E (125 ka), F?, G, and H, and correlate with interglacials from <10 ka (Holocene) to ca. 500 ka. In contrast, at the type locality of the Tamala Limestone along the Zuytdorp Cliffs, the upper eolianite-paleosol units are characterized by advanced stages of cavernous weathering, pedogenesis, and recrystallization. In the same units, sediment and snail samples generally yield very low or non-detectable levels of amino acids. These factors along with the stratigraphic complexity of the deposits reflect an age much greater than a large majority of sites along the WA coastline. These findings encourage a revision of the existing classification and nomenclature of Quaternary carbonate deposits in WA, as well as a reexamination of the underlying mechanisms related to the formation and emplacement of both carbonate and quartz dunes. 2008 Journal Article http://hdl.handle.net/20.500.11937/27920 http://www.sciencedirect.com/science/article/pii/S1871101407000477 Elsevier BV restricted |
| spellingShingle | Quaternary sea-level cycles Eolianite Bothriembryon land snails Amino acid epimerization dating Western Australia Limestone diagenesis Whole-rock Tamala Limestone Hearty, P. O'Leary, Mick Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title | Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title_full | Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title_fullStr | Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title_full_unstemmed | Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title_short | Carbonate eolianites, quartz sands, and Quaternary sea-level cycles, Western Australia: A chronostratigraphic approach |
| title_sort | carbonate eolianites, quartz sands, and quaternary sea-level cycles, western australia: a chronostratigraphic approach |
| topic | Quaternary sea-level cycles Eolianite Bothriembryon land snails Amino acid epimerization dating Western Australia Limestone diagenesis Whole-rock Tamala Limestone |
| url | http://www.sciencedirect.com/science/article/pii/S1871101407000477 http://hdl.handle.net/20.500.11937/27920 |