Constraining the colouration mechanisms of Cretaceous Oceanic Red Beds;using diffuse reflectance spectroscopy

doi:10.1016/j.cretres.2013.09.009

CORC > 中国地质调查局 > 中国地质调查局

	Constraining the colouration mechanisms of Cretaceous Oceanic Red Beds;using diffuse reflectance spectroscopy
	Li, Xiang 1; Cai, Yuanfeng 1,2
刊名	CRETACEOUS RESEARCH
	2013
卷号	46 页码:257-266
关键词	Cretaceous Oceanic Red Beds Hematite Diffuse reflectance spectroscopy Colouration mechanisms
ISSN号	0195-6671;EI 1095-998X
DOI	10.1016/j.cretres.2013.09.009
英文摘要	We have used diffuse reflectance spectroscopy to investigate the colouration mechanisms of hematite in Cretaceous Oceanic Red Beds (CORBs). Data for samples of CORBs from the Chuangde section in Tibet, Vispi Quarry section in Italy, and Core 12X of Ocean Drilling Program Hole 1049C in the North Atlantic were compared with calibration datasets obtained for hematite in different crystalline forms (kidney and specular hematite) and calcite matrix. Spectra for hematite in either pure form or in calibration datasets show that the centre of the reflection peak shifts to a longer wavelength and depth (D) decreases as the crystallinity of the hematite increases. Compared with specular hematite, the presence of just 0.5% of kidney hematite can cause a much deeper absorption peak and greater redness value, which indicates that kidney hematite has a higher colouration capacity than specular hematite. However, both kidney and specular hematite exhibit a good correlation between the redness value for each calibration dataset and the absorption peak depth. In all three studied sections, hematite is the main iron oxide mineral responsible for colouration. Spectral features such as absorption peak depth and peak centre reveal that hematite crystallinity gradually decreases from red shale to limestone to marl. Based on a spectral comparison of red shale in the Chuangde section before and after citrate-bicarbonate-dithionite (CBD) treatment, we found that two forms of hematite are present: a fine-grained and dispersed form, and a detrital form. The former is relatively poorly crystalline hematite, which has a much stronger colouration capacity than the detrital form. In the Vispi Quarry section and Core 12X of ODP Hole 1049C, a good correlation between the absorption peak depth of hematite and redness value indicates that the red colouration is caused by hematite of similar crystallinity in each section. (C) 2013 Elsevier Ltd. All rights reserved.
学科主题	地层学与地史学
WOS关键词	NORTH-ATLANTIC DRIFTS ; VISPI QUARRY SECTION ; PALEOCEANOGRAPHIC ; SIGNIFICANCE ; MINERALOGICAL CHARACTERISTICS ; VISIBLE SPECTROSCOPY ; MARINE-SEDIMENTS ; SOUTHERN TIBET ; OXIDE MINERALS ; IRON-OXIDES ; SOIL ; COLOR
WOS研究方向	Geology ; Paleontology
语种	英语
出版者	ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
WOS记录号	WOS:000329553900020
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/39917]
专题	中国地质调查局
作者单位	1.China Geol Survey, Wuhan Inst Geol & Mineral Resources, Wuhan 430223, Peoples R China. 2.Nanjing Univ, Sch Earth Sci & Engn, Nanjing 210046, Jiangsu, Peoples R China. 3.Nanjing Univ, State Key Lab Mineral Deposits Res, Nanjing 210046, Jiangsu, Peoples R China.
推荐引用方式 GB/T 7714	Li, Xiang,Cai, Yuanfeng. Constraining the colouration mechanisms of Cretaceous Oceanic Red Beds;using diffuse reflectance spectroscopy[J]. CRETACEOUS RESEARCH,2013,46:257-266.
APA	Li, Xiang,&Cai, Yuanfeng.(2013).Constraining the colouration mechanisms of Cretaceous Oceanic Red Beds;using diffuse reflectance spectroscopy.CRETACEOUS RESEARCH,46,257-266.
MLA	Li, Xiang,et al."Constraining the colouration mechanisms of Cretaceous Oceanic Red Beds;using diffuse reflectance spectroscopy".CRETACEOUS RESEARCH 46(2013):257-266.