气候变化领域集成服务门户(CCPortal): The Campanian paleoenvironment: Inferences based on benthic foraminifera from northeastern Iran

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DOI	10.1016/j.palaeo.2020.109823
	The Campanian paleoenvironment: Inferences based on benthic foraminifera from northeastern Iran
	Jain S.; Niazi M.; Abdelhady A.A.; Vahidinia M.; Hossein M.G.M.
发表日期	2020
ISSN	0031-0182
卷号	554
英文摘要	The benthic foraminifera from the Campanian rocks (Globotruncanita elevata to Globotruncana aegyptiaca zones) exposed in the Kopeh-Dagh Basin (northeast Iran) are studied quantitatively to reconstruct the Campanian paleoenvironment. Based on unconstrained heriarchial clustering, Nonmetric Multidimensional Scaling (NMDS), and analysis of similarity (ANOSIM), three statistically significant benthic foraminiferal assemblages are noted, Paralabamina lunata (lower and upper), Haplophragmoides spp., and Gyroidinoides nitida. Based on benthic foraminiferal marker species, the following paleodepths are assigned - lower P. lunata: upper bathyal; upper P. lunata: upper-middle bathyal boundary; Haplophragmoides spp. and G. nitida: outer neritic. The P. lunata Assemblage can be further subdivided into a lower Coryphostoma incrassata-dominated interval, whereas the upper interval is P. lunata-dominated, and reflects a change in the quality of food; the upper experienced higher input of fresh phytodetritus. The overall P. lunata Assemblage reflects a stable bottom water environment. The Haplophragmoides spp. Assemblage is characterized by reduced paleoproductivity and environmental instability, whereas the G. nitida Assemblage is marked by increasing oligotrophy within a well-oxygenated bottom water and ventilated basinal conditions. The Partial Least Squares regression yielded significant correlations with % Planktic (positive; proxy for sea level) and % agglutinated species (negative; proxy for shallow depths and low organic-flux); the Reduced Major Axis regression models also yielded significant negative correlations with % agglutinated and % infaunal species (nutrient availability), suggesting that these factors were responsible for the inferred benthic foraminiferal distribution patterns. Two globally comparable shallowing trends are also noted - one in the middle of the R. calcarata Zone (= Haplophragmoides spp. Assemblage) and the other in the G. aegyptiaca Zone (= Gyroidinoides nitida Assemblage) that coincide with KCa6 and KCa7 sequence boundaries and lowstands, respectively. For the KCa6 event, the occurrence of Spiroplectammina (= Haplophragmoides spp. Assemblage) represents a shallow-water outer neritic fauna invasion event within a deeper upper bathyal setting (= Paralabamina lunata Assemblage) and for the KCa7 event, a similar shallowing from upper-middle bathyal boundary to outer neritic depths is noted (= G. nitida Assemblage), and attributed to eustasy and basinal paleohighs and lows. © 2020 Elsevier B.V.
英文关键词	Eustasy; Foraminifera assemblage; Kopeh-Dagh Basin; Paleobathymetry; Paleoproductivity; Paleoxygenation
语种	英语
scopus关键词	benthic foraminifera; bottom water; Campanian; eustacy; food quality; nutrient availability; paleoenvironment; paleoproductivity; Iran; Foraminifera; Globotruncana aegyptiaca; Gyroidinoides; Haplophragmoides; Spiroplectammina
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/150425
作者单位	Department of Geology, School of Applied Natural Science, Adama Science and Technology University, Adama, Ethiopia; Department of Geology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran; Geology Department, Faculty of Science, Minia University, Minia, 61519, Egypt
推荐引用方式 GB/T 7714	Jain S.,Niazi M.,Abdelhady A.A.,et al. The Campanian paleoenvironment: Inferences based on benthic foraminifera from northeastern Iran[J],2020,554.
APA	Jain S.,Niazi M.,Abdelhady A.A.,Vahidinia M.,&Hossein M.G.M..(2020).The Campanian paleoenvironment: Inferences based on benthic foraminifera from northeastern Iran.Palaeogeography, Palaeoclimatology, Palaeoecology,554.
MLA	Jain S.,et al."The Campanian paleoenvironment: Inferences based on benthic foraminifera from northeastern Iran".Palaeogeography, Palaeoclimatology, Palaeoecology 554(2020).