Re-Visiting the Quantification of Hematite by Diffuse Reflectance Spectroscopy

Cao, Wei1; Jiang, Zhaoxia2,3,4; Gai, Congcong1; Barron, Vidal5; Torrent, Jose5; Zhong, Yi1; Liu, Qingsong1,6,7

2022-07-01

10.3390/min12070872

MINERALS   Impact Factor & Quartile

2075-163X

Hematite concentration is an important climatic proxy for environmental (climatic) studies of soils and sediments. However, the accurate quantification of naturally occurring hematite has always been a difficult question, especially for those areas with lower hematite concentrations. Diffuse reflectance spectroscopy (DRS) is an effective method for hematite identification and quantification with lower detection limits. In this study, we synthesized a set of samples with well-determined concentrations to explore the exact detectable range of hematite and propose the most effective transfer function between the DRS proxy and hematite concentration. In addition, natural sediments from Inland Asia and the Western Pacific Ocean were used to further test the feasibility of the new transfer function. Results show that the lowest DRS detection limit for hematite could reach similar to 0.00078%, but is affected by the natural matrix. We also find that the second derivative of the Kubelka-Munk (K-M) function is monotonically correlated with the hematite concentration (0.00078%-100%), but ambiguities exist for the first derivative. Therefore, the second derivative of the K-M function is highly suggested for the hematite quantification, especially when concentration exhibits a wide range of variations. This study provides important references for the application of hematite proxy and promotes the popularization and development of the DRS method.

environmental magnetism hematite diffuse reflectance spectroscopy detectable range detection limit Inland Asia Western Pacific Ocean

SCI

English

First ; Corresponding

National Natural Science Foundation of China["41922026","92158208","41874078","41806063"] ; National Key Research and Development Program of China[2016YFA061903] ; Shenzhen Science and Technology Program[KQTD20170810111725321] ; Shanghai Sheshan National Geophysical Observatory (Shanghai, China)[SSKP202101] ; China Postdoctoral Science Foundation[2021M701557]

Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing

Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing

WOS:000831429200001

MDPI

Web of Science

1.Southern Univ Sci & Technol, Ctr Marine Magnetism CM2, Dept Ocean Sci & Engn, Shenzhen 518055, Peoples R China
2.Ocean Univ China, Coll Marine Geosci, Frontiers Sci Ctr Deep Ocean Multispheres & Earth, Minist Educ,Key Lab Submarine Geosci & Prospectin, Qingdao 266100, Peoples R China
3.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Geol, Qingdao 266237, Peoples R China
4.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Mineral Resources, Qingdao 266237, Peoples R China
5.Univ Cordoba, Dept Agron, Edificio C4,Campus Rabanales, Cordoba 14071, Spain
6.Southern Marine Sci & Engn Guangdong Lab Guangzho, Guangzhou 511458, Peoples R China
7.Shanghai Sheshan Natl Geophys Observ, Shanghai 201602, Peoples R China

Cao, Wei,Jiang, Zhaoxia,Gai, Congcong,et al. Re-Visiting the Quantification of Hematite by Diffuse Reflectance Spectroscopy[J]. MINERALS,2022,12(7).

Cao, Wei.,Jiang, Zhaoxia.,Gai, Congcong.,Barron, Vidal.,Torrent, Jose.,...&Liu, Qingsong.(2022).Re-Visiting the Quantification of Hematite by Diffuse Reflectance Spectroscopy.MINERALS,12(7).

Cao, Wei,et al."Re-Visiting the Quantification of Hematite by Diffuse Reflectance Spectroscopy".MINERALS 12.7(2022).