气候变化领域集成服务门户(CCPortal): Unravelling calcrete environmental controls in volcanic islands; Gran Canaria Island; Spain

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DOI	10.1016/j.palaeo.2020.109797
	Unravelling calcrete environmental controls in volcanic islands; Gran Canaria Island; Spain
	Alonso-Zarza A.M.; Rodríguez-Berriguete Á.; Martín-Pérez A.; Martín-García R.; Menéndez I.; Mangas J.
发表日期	2020
ISSN	0031-0182
卷号	554
英文摘要	Volcanic islands are unique contexts to analyze the controls on calcrete development in settings with varied relief, climate and vegetation, and lacking carbonate host rocks. This paper discusses the formation of Quaternary calcrete profiles in Gran Canaria volcanic Island, under direct influence of the SAL (Saharian Air Layer). Calcrete profiles are multi-storey and composed of prismatic, massive, laminar, pisolithic, ooid-bearing, sandy mudstones with rhizoliths and brecciated horizons. Host rocks include basalts, siliceous mudstones, volcanic sands and gravels and bioclastic-rich sands. Carbonate is mostly calcite but some dolomite occurs in massive horizons. The main microfabrics include laminated micrite, fine crystalline dolomite, desiccated micrite, micrite-clay groundmass, oriented Mg-rich clays, peloids, spherulites and coated grains. δ13C varies from −3.26 to −9.18‰ VPDB and δ18O from +0.86 to −3.24‰ VPDB. The 87Sr/86Sr ratios are between 0.707504 and 0.708860, indicating that calcium was mostly supplied from the CaCO3-rich aeolian dust coming from the Sahara Desert. Calcrete profiles are mostly pedogenic with roots and microorganisms enabling carbonate precipitation within the soils. The correlation trend of δ13C and δ18O points to a climate control on precipitation, with the heavier isotope values in the horizons containing dolomite. Sedimentation rates interplayed with calcrete formation processes and erosion to outline the profiles/horizons. Amalgamated laminar horizons formed when the rate of calcrete formation was higher than sedimentation and erosion, whereas areas or periods with relatively higher sedimentation allowed the separation of calcrete horizons. The direction of the winds supplying aeolian dust, and the varied relief, vegetation and climate favored better development of calcretes in the relatively arid and lowland areas of the eastern side of the island. Our study shows that calcretes contain the record of the paleoenvironmental controls that operated in volcanic islands with no previous carbonate substrates. © 2020 Elsevier B.V.
英文关键词	Aeolian dust; Isotopes; Laminar horizons; Ooids; Pedogenic; Roots
语种	英语
scopus关键词	basalt; breccia; calcrete; carbon isotope; correlation; dolomite; host rock; magnesium; mudstone; oxygen isotope; precipitation (chemistry); sedimentation; soil profile; volcanic island; Canary Islands; Gran Canaria; Las Palmas; Sahara; Spain
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150443
作者单位	Departamento de Mineralogía y Petrología, Fac. CC. Geológicas, Instituto de Geociencias, CSIC. Universidad Complutense, C/ José Antonio Novais, 12, Madrid, 28040, Spain; Institute of Palaeontology Research Centre of the Slovenian Academy of Sciences and Arts, Novi trg 2, Ljubljana, 1000, Slovenia; Instituto de Oceanografía y Cambio Global, Facultad de Ciencias del Mar, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, 35017, Spain
推荐引用方式 GB/T 7714	Alonso-Zarza A.M.,Rodríguez-Berriguete Á.,Martín-Pérez A.,et al. Unravelling calcrete environmental controls in volcanic islands; Gran Canaria Island; Spain[J],2020,554.
APA	Alonso-Zarza A.M.,Rodríguez-Berriguete Á.,Martín-Pérez A.,Martín-García R.,Menéndez I.,&Mangas J..(2020).Unravelling calcrete environmental controls in volcanic islands; Gran Canaria Island; Spain.Palaeogeography, Palaeoclimatology, Palaeoecology,554.
MLA	Alonso-Zarza A.M.,et al."Unravelling calcrete environmental controls in volcanic islands; Gran Canaria Island; Spain".Palaeogeography, Palaeoclimatology, Palaeoecology 554(2020).