TY - GEN
T1 - Evaluation of limonite concretions by chemical and mineralogical composition, their formation model
AU - Kokins, Aigars
AU - Kostjukovs, Juris
AU - Meija, Raimonds
N1 - Funding Information:
This research was financially supported by the Latvian National Research Programme “ResProd” No. 2014.10-4/VPP-6/4.1 project “GEO”. The authors would like to thank the University of Latvia, the patron SIA “Mikrotīkls”, the University of Latvia Foundation and personally its Executive Director Laila Kundziņa-Zvejniece for their support.
Funding Information:
This research was financially supported by the Latvian National Research Programme “ResProd” No. 2014.10-4/VPP-6/4.1 project “GEO”.
Publisher Copyright:
© SGEM2018.
PY - 2018
Y1 - 2018
N2 - The formation conditions of limonite, often iron-oxide and hydroxide containing mineraloids can be related to the crystallisation process of iron oxides minerals in weathering crust sedimentation. Iron oxides (goethite, hematite) and their various admixtures form lithification compounds. The research involved the analysis of limonite concretions and their thin sections, composition analysis and interpreting the conditions of formation. Thin sections were examined by the difference in the formation of limonite ageing, colour, interpreting composition and colour range of tones depending on available chemical elements during their formation process, as well as granular composition. Two limonite formation models were interpreted – surface crust formation on top of other mineral aggregate (by evaporating mineral water solution), as well as the formation of limonite in the process of alluvial deposit. It was concluded, that the variation of the limonite tint depends on the degree of iron oxidation state, admixture of elements, fine grain practices and the environment of the formation, including the amount of water available. The mineral composition of limonite can be homogeneous or with polyphase structure, without noticeable change in colour, at the same time, the materials of relatively uniform mineral composition can be cardinally different in colour range.
AB - The formation conditions of limonite, often iron-oxide and hydroxide containing mineraloids can be related to the crystallisation process of iron oxides minerals in weathering crust sedimentation. Iron oxides (goethite, hematite) and their various admixtures form lithification compounds. The research involved the analysis of limonite concretions and their thin sections, composition analysis and interpreting the conditions of formation. Thin sections were examined by the difference in the formation of limonite ageing, colour, interpreting composition and colour range of tones depending on available chemical elements during their formation process, as well as granular composition. Two limonite formation models were interpreted – surface crust formation on top of other mineral aggregate (by evaporating mineral water solution), as well as the formation of limonite in the process of alluvial deposit. It was concluded, that the variation of the limonite tint depends on the degree of iron oxidation state, admixture of elements, fine grain practices and the environment of the formation, including the amount of water available. The mineral composition of limonite can be homogeneous or with polyphase structure, without noticeable change in colour, at the same time, the materials of relatively uniform mineral composition can be cardinally different in colour range.
KW - Earth colours
KW - Iron oxide/hydroxides
KW - Limonite
KW - Ochre
UR - http://www.scopus.com/inward/record.url?scp=85058816739&partnerID=8YFLogxK
U2 - 10.5593/sgem2018/1.1/S01.012
DO - 10.5593/sgem2018/1.1/S01.012
M3 - Conference contribution
AN - SCOPUS:85058816739
SN - 9786197408355
T3 - International Multidisciplinary Scientific Geoconference, SGEM
SP - 91
EP - 98
BT - 18th International Multidisciplinary Scientific GeoConference "Surveying Geology and Mining Ecology Management", SGEM 2018
T2 - 18th International Multidisciplinary Scientific Geoconference, SGEM 2018
Y2 - 2 July 2018 through 8 July 2018
ER -