Econ. Environ. Geol. 2021; 54(6): 767-785
Published online December 28, 2021
https://doi.org/10.9719/EEG.2021.54.6.767
© THE KOREAN SOCIETY OF ECONOMIC AND ENVIRONMENTAL GEOLOGY
Correspondence to : *shin@kongju.ac.kr
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided original work is properly cited.
World-class magnesite deposits are developed in the Dashiqiao mineralized district of the Jiao-Liao-Ji Belt in China. This belt extends to the northern side of the Korean Peninsula and hosts major magnesite deposits in the Dancheon region of North Korea. Magnesite ores from the Pailou deposits in the Dashiqiao district is classified into pure magnetite, chlorite-magnetite, chlorite-talc-magnetite, and dolomite groups depending on the constituent minerals. According to the result of petrographic study, magnesite was formed by the alteration of dolomite, and, talc, chlorite, and apatite were produced as late-stage alteration minerals that replaced the magnesite. Fluid inclusions observed in magnesite are a liquid-type inclusion, with a homogenization temperature of 121-250 °C and a salinity of 1.7-22.4 wt% NaCl equiv. The chlorite geothermometer, indicating the temperature of hydrothermal alteration, is 137~293 °C, slightly higher than the homogenization temperature of fluid inclusions, and the pressure is calculated to be less than 3.2 kb. For magnesite mineralization in the study area, the initially formed-dolomite was subjected to replacement by Mg-rich fluid to form a magnesite ore body, and then it was enriched through regional metamorphism and hydrothermal alteration. It seems that altered minerals such as talc were crystallized by Si and Al-rich late-stage hydrothermal fluids. These results are similar to the genetic environments of the Daeheung deposit, a representative magnesite deposit in North Korea, and it is believed that the two deposits went through a similar geological and ore genetic process of magnesite mineralization.
Keywords Pailou deposit, magnesite, fluid inclusion, chlorite geothermometer, Daeheung deposit
임헌경1 · 신동복1,2,* · 유봉철3
1공주대학교 지질환경과학과
2황해지질환경연구소
3한국지질자원연구원 자원탐사개발연구센터
중국 쟈오랴오지(Jiao-Liao-Ji) 벨트에 속한 다스챠오(Dashiqiao) 광화대에는 세계적 규모의 마그네사이트 광상들이 발달하며, 한반도 북측으로 연장되어 북한 단천지역 주요 마그네사이트 광상도 이에 속한다. 중국 다스챠오 광화대 팰로우(Pailou) 광상의 마그네사이트 광석은 구성광물에 따라 순수한 마그네사이트, 녹니석-마그네사이트, 녹니석-활석-마그네사이트, 그리고 돌로마이트 그룹으로 구분된다. 암석기재 연구결과 마그네사이트는 돌로마이트가 변질작용을 받아 형성되었음을 보여주며, 이를 다시 교대하는 후기 변질광물로 활석, 녹니석, 인회석 등이 산출된다. 마그네사이트내에 관찰되는 유체포유물은 액상포유물로서 균일화온도는 121~250 ℃, 염농도는 1.7~22.4 wt% NaCl equiv.의 범위를 보여준다. 열수변질작용의 온도를 지시하는 녹니석 지온계는 137~293 ℃로서 유체포유물의 균일화온도에 비해 약간 높으며, 이들의 생성압력은 3.2 kb 이하로 나타난다. 연구지역 마그네사이트 광화작용은 초기 형성된 돌로마이트가 Mg가 부화된 유체에 의한 교대작용을 받아 마그네사이트 광체를 형성하고, 이후 광역변성작용과 열수변질작용을 거치며 부화되였으며, Si 및 Al이 부화된 후기 열수에 의해 활석 등의 변질광물이 정출된 것으로 보인다. 이러한 결과는 북한의 대표적인 대흥 마그네사이트 광상의 정출환경과 유사하며 두 광상이 상호 유사한 지질광상학적 생성과정을 거치며 광화작용이 진행된 것으로 여겨진다.
주요어 중국 팰로우광상, 마그네사이트, 유체포유물, 녹니석 지온계, 북한 대흥광상
Econ. Environ. Geol. 2021; 54(6): 767-785
Published online December 28, 2021 https://doi.org/10.9719/EEG.2021.54.6.767
Copyright © THE KOREAN SOCIETY OF ECONOMIC AND ENVIRONMENTAL GEOLOGY.
Heonkyung Im1, Dongbok Shin1,2,*, Bong-chul Yoo3
1Department of Geoenvironmental Sciences, Kongju National University, Gongju 32588, Republic of Korea
2Yellow Sea Institute of Geoenvironmental Sciences, Kongju National University, Gongju 32588, Republic of Korea
3Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, Republic of Korea
Correspondence to:*shin@kongju.ac.kr
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided original work is properly cited.
World-class magnesite deposits are developed in the Dashiqiao mineralized district of the Jiao-Liao-Ji Belt in China. This belt extends to the northern side of the Korean Peninsula and hosts major magnesite deposits in the Dancheon region of North Korea. Magnesite ores from the Pailou deposits in the Dashiqiao district is classified into pure magnetite, chlorite-magnetite, chlorite-talc-magnetite, and dolomite groups depending on the constituent minerals. According to the result of petrographic study, magnesite was formed by the alteration of dolomite, and, talc, chlorite, and apatite were produced as late-stage alteration minerals that replaced the magnesite. Fluid inclusions observed in magnesite are a liquid-type inclusion, with a homogenization temperature of 121-250 °C and a salinity of 1.7-22.4 wt% NaCl equiv. The chlorite geothermometer, indicating the temperature of hydrothermal alteration, is 137~293 °C, slightly higher than the homogenization temperature of fluid inclusions, and the pressure is calculated to be less than 3.2 kb. For magnesite mineralization in the study area, the initially formed-dolomite was subjected to replacement by Mg-rich fluid to form a magnesite ore body, and then it was enriched through regional metamorphism and hydrothermal alteration. It seems that altered minerals such as talc were crystallized by Si and Al-rich late-stage hydrothermal fluids. These results are similar to the genetic environments of the Daeheung deposit, a representative magnesite deposit in North Korea, and it is believed that the two deposits went through a similar geological and ore genetic process of magnesite mineralization.
Keywords Pailou deposit, magnesite, fluid inclusion, chlorite geothermometer, Daeheung deposit
임헌경1 · 신동복1,2,* · 유봉철3
1공주대학교 지질환경과학과
2황해지질환경연구소
3한국지질자원연구원 자원탐사개발연구센터
중국 쟈오랴오지(Jiao-Liao-Ji) 벨트에 속한 다스챠오(Dashiqiao) 광화대에는 세계적 규모의 마그네사이트 광상들이 발달하며, 한반도 북측으로 연장되어 북한 단천지역 주요 마그네사이트 광상도 이에 속한다. 중국 다스챠오 광화대 팰로우(Pailou) 광상의 마그네사이트 광석은 구성광물에 따라 순수한 마그네사이트, 녹니석-마그네사이트, 녹니석-활석-마그네사이트, 그리고 돌로마이트 그룹으로 구분된다. 암석기재 연구결과 마그네사이트는 돌로마이트가 변질작용을 받아 형성되었음을 보여주며, 이를 다시 교대하는 후기 변질광물로 활석, 녹니석, 인회석 등이 산출된다. 마그네사이트내에 관찰되는 유체포유물은 액상포유물로서 균일화온도는 121~250 ℃, 염농도는 1.7~22.4 wt% NaCl equiv.의 범위를 보여준다. 열수변질작용의 온도를 지시하는 녹니석 지온계는 137~293 ℃로서 유체포유물의 균일화온도에 비해 약간 높으며, 이들의 생성압력은 3.2 kb 이하로 나타난다. 연구지역 마그네사이트 광화작용은 초기 형성된 돌로마이트가 Mg가 부화된 유체에 의한 교대작용을 받아 마그네사이트 광체를 형성하고, 이후 광역변성작용과 열수변질작용을 거치며 부화되였으며, Si 및 Al이 부화된 후기 열수에 의해 활석 등의 변질광물이 정출된 것으로 보인다. 이러한 결과는 북한의 대표적인 대흥 마그네사이트 광상의 정출환경과 유사하며 두 광상이 상호 유사한 지질광상학적 생성과정을 거치며 광화작용이 진행된 것으로 여겨진다.
주요어 중국 팰로우광상, 마그네사이트, 유체포유물, 녹니석 지온계, 북한 대흥광상
Table 1 . Petrographic descriptions of magnesite ores and dolostones in the Pailou deposit.
Rock type | Group | Sample No. | Minerals | Lithology |
---|---|---|---|---|
Magnesite | Pure Mgs | 19PL-6 | Mgs±Qtz | White, coarse grained, Qtz vein |
19PL-6-2 | Mgs±Qtz±Dol±Apt | White and gray, coarse grained, Qtz+Apt vein | ||
19PL-7 | Mgs+Qtz±Dol | Pinkish white, coarse grained, Qtz vein | ||
19PL-10a | Mgs+Qtz±Tlc±Dol | Pinkish white, coarse grained, Qtz vein | ||
19PL-13 | Mgs±Cc | Pinkish, coarse grained, Cc vein | ||
19PL-13-1 | Mgs, Qtz | Pinkish white, coarse grained, Qtz vein | ||
19PL-13-3 | Mgs+Dol | Pinkish, coarse grained, Dol vein | ||
19PL-13-4 | Mgs±Dol | Pinkish, coarse grained, Dol vein | ||
Chl+Mgs | 19PL-6-1 | Mgs±Qtz±Chl±Apt | White and gray, coarse grained, Qtz+Chl+Apt vein | |
19PL-9 | Mgs±Chl±Dol | Pinkish white, coarse grained, Chl+Dol vein | ||
19PL-11 | Mgs±Chl±Tlc | White, coarse grained, Chl+Tlc vein | ||
19PL-13-2 | Mgs±Dol±Chl±Apt | Pinkish, coarse grained, Chl+Apt and Dol vein | ||
Chl+Tlc+Mgs | 19PL-2-1 | Mgs+Tlc+Chl±Apt | Gray, coarse to medium grained, Chl+Tlc+Apt vein | |
19PL-2-2 | Mgs+Tlc+Chl±Apt | Dark gray, coarse to medium grained, Chl+Tlc+Apt vein | ||
19PL-3-1 | Mgs+Tlc+Chl | White,coarsetomediumgrained, Chl+Tlc vein | ||
19PL-3-2 | Mgs+Tlc+Chl±Apt | White,coarsetomediumgrained, Chl+Tlc+Apt vein | ||
19PL-8a | Mgs+Tlc+Chl±Dol | Gray, coarse grained, Chl+Tlc vein | ||
19PL-10b | Mgs+Tlc+Chl±Apt | Pinkish white, coarse grained, Chl+Tlc+Apt vein | ||
Dolostone | Dol | 19PL-1 | Dol±Qtz | White, fine grained, Dol vein |
19PL-4 | Dol±Chl | Dark gray, fine grained, Dol vein | ||
19PL-5 | Dol+Qtz±Apt | White, coarse to medium grained, Qtz vein | ||
19PL-12 | Dol±Apt | Dark gray, fine grained, Qtz vein |
Table 2 . Electron microprobe analysis of dolomite in the Pailou deposit.
Sample No. | Type | SiO2 | Al2O3 | FeO | MnO | MgO | CaO | Total |
---|---|---|---|---|---|---|---|---|
19PL-1 | host | 0.30 | 0.01 | 21.75 | 29.41 | 51.46 | | |
19PL-1 | vein | 0.02 | 0.59 | 0.12 | 21.21 | 28.90 | 50.84 | |
19PL-1 | host | 0.31 | 0.05 | 21.13 | 29.57 | 51.06 | | |
19PL-3-1 | residue | 0.10 | 21.59 | 30.35 | 52.04 | | ||
19PL-3-1 | residue | 0.11 | 22.01 | 30.50 | 52.62 | | ||
19PL-3-1 | residue | 0.03 | 0.06 | 0.02 | 21.75 | 30.49 | 52.35 | |
19PL-4 | vein | 0.33 | 0.05 | 21.92 | 30.14 | 52.44 | | |
19PL-4 | host | 0.01 | 0.63 | 0.03 | 21.50 | 30.78 | 52.94 | |
19PL-4 | host | 0.10 | 0.04 | 22.02 | 30.66 | 52.82 | | |
19PL-4 | vein | 0.44 | 21.56 | 30.24 | 52.23 | | ||
19PL-5 | host | 0.04 | 0.01 | 21.83 | 30.48 | 52.37 | | |
19PL-5 | host | 0.00 | 0.08 | 0.03 | 21.85 | 30.35 | 52.32 | |
19PL-5 | host | 0.05 | 21.60 | 30.53 | 52.18 | | ||
19PL-5 | host | 0.03 | 0.02 | 22.05 | 30.39 | 52.49 | | |
19PL-5 | host | 0.04 | 0.01 | 22.13 | 30.70 | 52.88 | | |
19PL-5 | host | 0.02 | 0.04 | 21.93 | 30.64 | 52.62 | | |
19PL-5 | host | 0.03 | 0.07 | 22.04 | 30.48 | 52.61 | | |
19PL-6-2 | residue | 0.12 | 0.05 | 21.76 | 30.23 | 52.16 | | |
19PL-6-2 | residue | 0.03 | 0.08 | 0.01 | 21.67 | 30.94 | 52.73 | |
19PL-6-2 | residue | 0.07 | 0.02 | 21.85 | 29.95 | 51.89 | | |
19PL-7 | residue | 0.02 | 0.10 | 0.04 | 21.31 | 29.44 | 50.90 | |
19PL-7 | residue | 0.07 | 0.11 | 0.06 | 21.38 | 29.87 | 51.48 | |
19PL-7 | residue | 0.12 | 0.04 | 21.35 | 30.29 | 51.80 | | |
19PL-8a | residue | 0.07 | 22.05 | 30.74 | 52.86 | | ||
19PL-8a | residue | 0.01 | 0.12 | 0.01 | 21.94 | 30.59 | 52.66 | |
19PL-9 | vein | 0.02 | 0.07 | 21.85 | 29.85 | 51.78 | | |
19PL-9 | vein | 0.01 | 0.03 | 0.03 | 21.65 | 30.01 | 51.73 | |
19PL-10a | vein | 0.06 | 21.62 | 30.30 | 51.97 | | ||
19PL-12 | host | 0.01 | 0.46 | 0.04 | 21.86 | 30.86 | 53.23 | |
19PL-12 | host | 0.08 | 0.75 | 0.01 | 21.38 | 30.06 | 52.29 | |
19PL-13-2 | vein | 0.02 | 0.03 | 21.21 | 30.20 | 51.45 | | |
19PL-13-2 | vein | 0.01 | 0.09 | 22.13 | 29.96 | 52.20 | | |
19PL-13-3 | host | 0.02 | 0.12 | 0.05 | 21.82 | 30.40 | 52.41 | |
19PL-13-3 | host | 0.05 | 21.74 | 30.01 | 51.80 | | ||
19PL-13-3 | vein | 0.02 | 0.15 | 0.04 | 21.58 | 29.80 | 51.59 | |
19PL-13-3 | vein | 0.01 | 0.09 | 0.02 | 21.41 | 30.35 | 51.88 | |
19PL-13-4 | vein | 0.03 | 0.06 | 21.60 | 29.90 | 51.59 | | |
19PL-13-4 | vein | 0.08 | 21.34 | 29.68 | 51.09 | |
Table 3 . Electron microprobe analysis of magnesite in the Pailou deposit.
Group | Sample No. | SiO2 | Al2O3 | FeO | MnO | MgO | CaO | Total |
---|---|---|---|---|---|---|---|---|
Pure Mgs | 19PL-6 | 0.03 | 0.27 | 0.03 | 47.09 | 0.02 | 47.45 | |
19PL-6 | 0.02 | 0.28 | 0.02 | 46.96 | 0.66 | 47.93 | | |
19PL-6-2 | 0.02 | 0.03 | 0.35 | 0.07 | 45.77 | 0.67 | 46.89 | |
19PL-6-2 | 0.05 | 0.34 | 0.03 | 46.03 | 0.44 | 46.89 | | |
19PL-6-2 | 0.33 | 0.04 | 45.78 | 0.75 | 46.90 | | ||
19PL-7 | 0.49 | 0.02 | 45.65 | 0.85 | 47.02 | | ||
19PL-10a | 0.02 | 0.22 | 0.00 | 46.08 | 0.65 | 46.98 | | |
19PL-10a | 0.05 | 0.05 | 0.12 | 0.02 | 46.15 | 0.19 | 46.57 | |
19PL-10a | 0.02 | 0.22 | 0.06 | 46.16 | 0.12 | 46.57 | | |
19PL-10a | 0.19 | 46.89 | 0.19 | 47.27 | | |||
19PL-13 | 0.04 | 0.63 | 0.04 | 45.86 | 0.36 | 46.92 | | |
19PL-13 | 0.00 | 0.59 | 0.05 | 45.76 | 0.44 | 46.84 | | |
19PL-13-1 | 0.01 | 0.34 | 0.01 | 47.54 | 0.28 | 48.18 | | |
19PL-13-2 | 0.02 | 0.01 | 0.39 | 0.06 | 45.98 | 0.72 | 47.18 | |
19PL-13-2 | 0.03 | 0.38 | 0.02 | 45.80 | 0.68 | 46.91 | | |
19PL-13-3 | 0.03 | 0.01 | 0.38 | 0.01 | 45.98 | 0.01 | 46.42 | |
19PL-13-3 | 0.05 | 46.92 | 0.16 | 47.12 | | |||
19PL-13-3 | 0.00 | 0.19 | 0.02 | 46.81 | 0.17 | 47.20 | | |
19PL-13-3 | 0.02 | 0.21 | 0.01 | 46.41 | 0.78 | 47.44 | | |
19PL-13-4 | 0.01 | 0.27 | 0.04 | 46.33 | 0.12 | 46.77 | | |
19PL-13-4 | 0.00 | 0.41 | 0.01 | 46.17 | 0.53 | 47.12 | | |
Chl+Mgs | 19PL-6-1 | 0.03 | 0.21 | 0.04 | 46.40 | 0.63 | 47.32 | |
19PL-9 | 0.08 | 0.01 | 46.93 | 0.33 | 47.35 | | ||
19PL-11 | 0.01 | 0.24 | 0.07 | 46.49 | 0.97 | 47.78 | | |
19PL-11 | 0.23 | 0.06 | 47.19 | 0.33 | 47.80 | | ||
Chl+Tlc+Mgs | 19PL-2-1 | 0.33 | 46.12 | 0.68 | 47.13 | | ||
19PL-2-1 | 0.34 | 0.04 | 46.00 | 0.59 | 46.97 | | ||
19PL-2-1 | 0.04 | 0.34 | 0.03 | 46.37 | 0.06 | 46.83 | | |
19PL-2-1 | 0.37 | 0.02 | 45.92 | 0.71 | 47.03 | | ||
19PL-2-2 | 0.03 | 0.00 | 0.19 | 46.18 | 0.17 | 46.56 | | |
19PL-2-2 | 0.01 | 0.05 | 0.20 | 0.01 | 46.82 | 0.01 | 47.09 | |
19PL-3-1 | 0.01 | 0.27 | 47.32 | 0.31 | 47.91 | | ||
19PL-3-1 | 0.21 | 0.04 | 46.35 | 0.52 | 47.12 | | ||
19PL-3-2 | 0.01 | 0.20 | 0.05 | 46.61 | 0.66 | 47.53 | | |
19PL-3-2 | 0.03 | 0.22 | 0.05 | 45.95 | 0.42 | 46.67 | | |
19PL-8a | 0.03 | 0.49 | 0.05 | 47.64 | 0.03 | 48.23 | | |
19PL-10b | 0.26 | 47.29 | 0.04 | 47.60 | | |||
19PL-10b | 0.00 | 0.42 | 46.87 | 0.04 | 47.32 | | ||
19PL-10b | 0.21 | 0.06 | 46.96 | 0.20 | 47.43 | | ||
19PL-10b | 0.23 | 0.02 | 46.69 | 0.75 | 47.70 | | ||
19PL-10b | 0.03 | 0.00 | 0.17 | 0.00 | 46.57 | 0.90 | 47.68 |
Table 4 . Electron microprobe analysis of chlorite in the Pailou deposit.
Groups | Chl+Mgs | Chl+Tlc+Mgs | ||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sample No. | 19PL-6-1 | 19PL-9 | 19PL-11 | 19PL-13-2 | 19PL-2-1 | 19PL-2-2 | 19PL-3-1 | 19PL-3-2 | 19PL-8a | 19PL-10b | ||||||||||||||||||||||||||||||||||||
Analysis No. | 1 | 3 | 4 | 5 | 6 | 7 | 3 | 4 | 5 | 3 | 4 | 5 | 2 | 2 | 3 | 5 | 6 | 8 | 9 | 10 | 1 | 2 | 5 | 6 | 1 | 2 | 5 | 6 | 7 | 3 | 4 | 5 | 9 | 10 | 11 | 3 | 4 | 5 | 1 | 2 | 3 | 7 | 8 | 9 | 12 | 13 |
SiO2 | 42.56 | 33.86 | 34.61 | 33.93 | 34.93 | 38.12 | 39.05 | 36.86 | 37.34 | 33.46 | 33.24 | 32.69 | 42.61 | 33.17 | 35.72 | 32.81 | 32.22 | 31.62 | 35.74 | 33.28 | 30.92 | 32.30 | 31.17 | 32.39 | 32.77 | 32.74 | 32.76 | 35.18 | 32.20 | 31.82 | 32.42 | 34.79 | 31.78 | 32.57 | 31.40 | 33.65 | 34.84 | 33.25 | 32.14 | 31.84 | 31.48 | 32.76 | 36.18 | 32.64 | 32.36 | 32.02 |
TiO2 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | 0.03 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.02 | 0.00 | 0.00 | 0.00 | 0.03 | 0.00 | 0.00 | 0.01 | 0.02 | 0.00 | 0.00 | 0.01 | 0.02 | 0.01 | 0.01 | 0.01 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Al2O3 | 12.46 | 12.56 | 16.49 | 13.23 | 16.68 | 12.71 | 17.66 | 16.61 | 16.55 | 16.79 | 16.05 | 15.85 | 15.96 | 16.44 | 15.90 | 17.90 | 18.47 | 17.69 | 14.93 | 17.26 | 19.87 | 17.94 | 19.95 | 19.13 | 17.34 | 17.78 | 16.95 | 15.74 | 18.53 | 18.41 | 18.60 | 17.37 | 19.10 | 19.68 | 19.65 | 16.59 | 16.33 | 18.66 | 19.08 | 19.81 | 20.66 | 18.97 | 14.67 | 20.76 | 20.00 | 19.28 |
FeO | 0.13 | 0.17 | 0.09 | 0.16 | 0.11 | 0.21 | 0.24 | 0.15 | 0.16 | 0.16 | 0.14 | 0.14 | 0.32 | 0.15 | 0.18 | 0.11 | 0.19 | 0.23 | 0.15 | 0.18 | 0.16 | 0.13 | 0.16 | 0.24 | 0.11 | 0.14 | 0.13 | 0.12 | 0.13 | 0.27 | 0.23 | 0.17 | 0.37 | 0.34 | 0.30 | 0.17 | 0.20 | 0.23 | 0.16 | 0.13 | 0.14 | 0.17 | 0.18 | 0.17 | 0.16 | 0.20 |
MnO | 0.00 | 0.02 | 0.01 | 0.00 | 0.00 | 0.00 | 0.04 | 0.02 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.04 | 0.00 | 0.02 | 0.02 | 0.01 | 0.03 | 0.00 | 0.00 | 0.00 | 0.01 | 0.02 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.01 | 0.00 | 0.03 | 0.03 | 0.01 | 0.00 | 0.00 | 0.00 | 0.02 | 0.02 |
MgO | 23.86 | 32.19 | 34.40 | 33.04 | 25.14 | 29.32 | 27.14 | 25.74 | 26.72 | 35.52 | 35.50 | 35.86 | 29.15 | 35.03 | 33.74 | 34.15 | 34.32 | 34.23 | 34.16 | 33.85 | 33.90 | 34.60 | 33.63 | 33.43 | 34.93 | 34.62 | 35.19 | 34.19 | 34.37 | 34.95 | 34.07 | 34.26 | 33.79 | 32.45 | 33.82 | 35.40 | 35.06 | 34.85 | 33.34 | 32.44 | 32.06 | 33.39 | 34.78 | 32.24 | 33.13 | 33.36 |
CaO | 0.03 | 0.32 | 0.09 | 0.13 | 0.08 | 0.47 | 0.10 | 0.11 | 0.25 | 0.03 | 0.02 | 0.01 | 0.26 | 0.01 | 0.03 | 0.01 | 0.03 | 0.04 | 0.01 | 0.03 | 0.04 | 0.05 | 0.02 | 0.02 | 0.05 | 0.01 | 0.02 | 0.01 | 0.02 | 0.07 | 0.03 | 0.04 | 0.02 | 0.01 | 0.02 | 0.02 | 0.02 | 0.01 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.02 | 0.02 | 0.02 |
Na2O | 0.00 | 0.08 | 0.00 | 0.01 | 0.02 | 0.05 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.01 | 0.04 | 0.01 | 0.04 | 0.02 | 0.00 | 0.05 | 0.00 | 0.00 | 0.01 | 0.02 | 0.09 | 0.06 | 0.00 | 0.00 | 0.01 | 0.01 | 0.02 | 0.02 | 0.00 | 0.02 | 0.04 | 0.00 | 0.02 | 0.00 | 0.02 | 0.00 | 0.01 | 0.03 | 0.01 | 0.00 | 0.00 | 0.00 |
K2O | 0.01 | 0.03 | 0.00 | 0.01 | 0.00 | 0.05 | 0.13 | 0.02 | 0.01 | 0.00 | 0.01 | 0.00 | 0.09 | 0.01 | 0.01 | 0.01 | 0.00 | 0.02 | 0.02 | 0.02 | 0.00 | 0.00 | 0.00 | 0.03 | 0.07 | 0.02 | 0.00 | 0.01 | 0.01 | 0.01 | 0.00 | 0.02 | 0.02 | 0.04 | 0.00 | 0.02 | 0.00 | 0.03 | 0.01 | 0.01 | 0.01 | 0.03 | 0.02 | 0.01 | 0.02 | 0.00 |
Cr2O3 | 0.01 | 0.00 | 0.01 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.03 | 0.01 | 0.01 | 0.02 | 0.00 | 0.00 | 0.02 | 0.01 | 0.02 | 0.00 | 0.03 | 0.00 | 0.03 | 0.04 | 0.01 | 0.00 | 0.03 | 0.04 | 0.02 | 0.00 | 0.00 | 0.02 | 0.01 | 0.06 | 0.04 | 0.02 | 0.00 | 0.00 | 0.01 | 0.04 | 0.03 | 0.01 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 |
F | 0.53 | 0.45 | 0.10 | 0.20 | 0.26 | 0.82 | 0.79 | 0.43 | 0.69 | 0.16 | 0.07 | 0.00 | 1.78 | 0.16 | 0.03 | 0.00 | 0.16 | 0.10 | 0.00 | 0.19 | 0.51 | 0.35 | 0.32 | 0.42 | 0.00 | 0.48 | 0.23 | 0.16 | 0.19 | 0.23 | 0.19 | 0.52 | 0.16 | 0.23 | 0.39 | 0.35 | 0.19 | 0.48 | 0.00 | 0.00 | 0.13 | 0.00 | 0.07 | 0.00 | 0.16 | 0.00 |
Cl | 0.00 | 0.01 | 0.02 | 0.00 | 0.01 | 0.04 | 0.03 | 0.02 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.02 | 0.01 | 0.02 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.01 | 0.04 | 0.02 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.01 | 0.01 | 0.00 | 0.03 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.00 |
Total | 79.59 | 79.69 | 85.81 | 80.71 | 77.24 | 81.81 | 85.17 | 79.94 | 81.74 | 86.16 | 85.03 | 84.56 | 90.19 | 85.01 | 85.67 | 85.04 | 85.44 | 83.99 | 85.03 | 84.94 | 85.40 | 85.43 | 85.32 | 85.70 | 85.43 | 85.91 | 85.32 | 85.43 | 85.51 | 85.79 | 85.59 | 87.20 | 85.33 | 85.38 | 85.65 | 86.22 | 86.70 | 87.56 | 84.85 | 84.33 | 84.54 | 85.40 | 85.93 | 85.85 | 85.88 | 84.91 |
Cations based on 28 oxygen | ||||||||||||||||||||||||||||||||||||||||||||||
Si | 7.14 | 7.05 | 6.77 | 6.45 | 6.71 | 7.09 | 7.31 | 5.96 | 6.07 | 6.35 | 5.98 | 6.10 | 5.87 | 6.26 | 6.65 | 6.19 | 6.05 | 6.05 | 6.71 | 6.27 | 5.80 | 6.06 | 5.85 | 6.04 | 6.17 | 6.09 | 6.16 | 6.57 | 6.04 | 7.30 | 6.07 | 6.35 | 5.98 | 6.10 | 5.87 | 6.25 | 6.43 | 6.07 | 6.23 | 6.28 | 6.23 | 6.25 | 6.43 | 6.07 | 7.15 | 7.21 |
Al(IV) | 0.86 | 0.95 | 1.23 | 1.55 | 1.29 | 0.91 | 0.69 | 2.04 | 1.93 | 1.65 | 2.02 | 1.90 | 2.13 | 1.74 | 1.35 | 1.81 | 1.95 | 1.95 | 1.29 | 1.73 | 2.20 | 1.94 | 2.15 | 1.96 | 1.83 | 1.91 | 1.84 | 1.43 | 1.96 | 0.70 | 1.93 | 1.65 | 2.02 | 1.90 | 2.13 | 1.75 | 1.57 | 1.93 | 1.77 | 1.72 | 1.77 | 1.75 | 1.57 | 1.93 | 0.85 | 0.79 |
Al(VI) | 2.90 | 1.99 | 1.74 | 2.08 | 1.81 | 3.09 | 2.21 | 2.04 | 2.19 | 2.11 | 2.23 | 2.45 | 2.23 | 1.92 | 2.15 | 2.17 | 2.15 | 2.05 | 2.02 | 2.11 | 2.21 | 2.04 | 2.29 | 2.26 | 2.02 | 2.02 | 1.93 | 2.05 | 2.15 | 2.59 | 2.19 | 2.11 | 2.23 | 2.45 | 2.23 | 1.89 | 1.99 | 2.11 | 1.92 | 1.86 | 1.78 | 1.89 | 1.99 | 2.11 | 3.00 | 3.06 |
Ti | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Cr | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Fe3+ | 0.03 | 0.02 | 0.03 | 0.01 | 0.03 | 0.02 | 0.03 | 0.04 | 0.04 | 0.03 | 0.06 | 0.05 | 0.05 | 0.02 | 0.03 | 0.02 | 0.03 | 0.04 | 0.02 | 0.03 | 0.03 | 0.02 | 0.03 | 0.04 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.05 | 0.04 | 0.03 | 0.06 | 0.05 | 0.05 | 0.03 | 0.03 | 0.03 | 0.03 | 0.02 | 0.01 | 0.03 | 0.03 | 0.03 | 0.04 | 0.02 |
Fe2+ | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Mn | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 |
Mg | 7.61 | 9.28 | 9.59 | 9.56 | 9.75 | 7.61 | 8.38 | 9.76 | 9.51 | 9.33 | 9.48 | 9.05 | 9.43 | 9.85 | 9.37 | 9.60 | 9.60 | 9.77 | 9.57 | 9.51 | 9.47 | 9.67 | 9.42 | 9.29 | 9.80 | 9.61 | 9.87 | 9.52 | 9.61 | 7.45 | 9.51 | 9.33 | 9.48 | 9.05 | 9.43 | 9.80 | 9.64 | 9.48 | 9.86 | 10.00 | 10.18 | 9.80 | 9.64 | 9.48 | 7.41 | 7.50 |
Ca | 0.05 | 0.03 | 0.07 | 0.02 | 0.03 | 0.02 | 0.10 | 0.01 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.01 | 0.00 | 0.01 | 0.01 | 0.01 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.05 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.02 |
Na | 0.00 | 0.00 | 0.06 | 0.00 | 0.01 | 0.02 | 0.04 | 0.01 | 0.01 | 0.01 | 0.00 | 0.01 | 0.03 | 0.01 | 0.03 | 0.01 | 0.03 | 0.01 | 0.00 | 0.04 | 0.00 | 0.00 | 0.01 | 0.01 | 0.06 | 0.04 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.01 | 0.03 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 |
K | 0.00 | 0.00 | 0.02 | 0.00 | 0.01 | 0.00 | 0.03 | 0.01 | 0.00 | 0.01 | 0.01 | 0.02 | 0.00 | 0.01 | 0.01 | 0.01 | 0.00 | 0.01 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.03 | 0.01 | 0.00 | 0.01 | 0.00 | 0.04 | 0.00 | 0.01 | 0.01 | 0.02 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.01 | 0.06 | 0.01 |
F | 0.83 | 0.32 | 0.57 | 0.11 | 0.24 | 0.34 | 0.99 | 0.27 | 0.23 | 0.60 | 0.19 | 0.27 | 0.46 | 0.19 | 0.04 | 0.00 | 0.19 | 0.12 | 0.00 | 0.23 | 0.61 | 0.42 | 0.38 | 0.49 | 0.00 | 0.57 | 0.27 | 0.19 | 0.23 | 1.93 | 0.23 | 0.60 | 0.19 | 0.27 | 0.46 | 0.42 | 0.23 | 0.56 | 0.19 | 0.08 | 0.00 | 0.42 | 0.23 | 0.56 | 0.91 | 0.53 |
Cl | 0.01 | 0.01 | 0.01 | 0.01 | 0.00 | 0.00 | 0.03 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.02 | 0.01 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.01 | 0.00 | 0.01 | 0.01 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.02 | 0.02 | 0.01 |
Fe/(Fe+Mg) | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 |
T(°C)* | - | - | 136.8 | 187.5 | 145.1 | - | - | 266.5 | 248.6 | 203.2 | 263.5 | 244.7 | 280.5 | 218.6 | 154.7 | 229.4 | 252.1 | 251.8 | 145.1 | 216.7 | 292.9 | 250.7 | 283.4 | 253.9 | 233.3 | 245.1 | 234.1 | 168.0 | 253.7 | - | 248.6 | 203.2 | 263.5 | 244.7 | 280.5 | 220.3 | 191.4 | 248.7 | 222.8 | 215.0 | 223.8 | 220.3 | 191.4 | 248.7 | - | - |
* data calculated by Cathelineau and Nieva (1995).
Table 5 . Summary of microthermometric data of fluid inclusions from the Pailou deposit.
Groups | Sample No. | Inclusion type | Numberof analysis | Size(㎛) | Th(℃) | Tmice(℃) | Salinity (wt%NaCl) | P(bar) |
---|---|---|---|---|---|---|---|---|
Pure Mgs | 19PL-6 | Liquid-rich | 21 | < 8 | 145~239 | -12~-2 | 3.4~16.0 | 4.1~32.0 |
19PL-6-2 | Liquid-rich | 8 | < 8 | 140~243 | -9~-3 | 5.0~12.8 | 10.0~32.5 | |
19PL-10a | Liquid-rich | 8 | < 4 | 130~161 | -5~-2 | 3.4~7.9 | 2.6~3.3 | |
19PL-13 | Liquid-rich | 14 | < 4 | 134~213 | -20~-5 | 7.9~22.3 | 2.7~17.0 | |
19PL-13-1 | Liquid-rich | 7 | < 4 | 173~220 | -12~-9 | 12.8~16.0 | 7.5~13.6 | |
Chl+Mgs | 19PL-6-1 | Liquid-rich | 12 | < 8 | 150~220 | -18~-1 | 1.7~21.0 | 4.4~13.5 |
19PL-11 | Liquid-rich | 8 | < 6 | 143~171 | -6~-1 | 1.7~9.2 | 3.9~7.6 | |
Chl+Tlc+Mgs | 19PL-2-1, 2-2 | Liquid-rich | 9 | < 10 | 163~224 | -12~-4 | 6.4~16.0 | 11.0~23.6 |
19PL-8a | Liquid-rich | 32 | < 11 | 121~250 | -20~-2 | 3.4~22.4 | 2.0~10.6 |
Table 6 . Comparison of deposit characteristics between the Dashiqiao and Dancheon magnesite deposits.
Dashiqiao (China) | Dancheon (North Korea) | |
---|---|---|
Host rock | • dolostone | • dolostone |
Formation | • Dashiqiao Formation (Proterozoic) | • Bukdaecheon Series (Proterozoic) |
Orebody | • white, gray, pinkish color • sparry texture • residual dolomite • talc-chlorite vein • dolomite, calcite vein | • pinkish, white, gray color • sparry texture • residual dolomite • talc-chlorite vein |
Minerals | • major magnesite, talc • minor chlorite, apatite, quartz | • major magnesite • minor talc, chlorite, apatite, quartz, tremolite |
Chlorite composition | • clinochlore, penninite, talc-chlorite | • mostly clinochlore |
Homogenization temperature and salinity | • 121~250 ℃ (avg. 175 ℃) • 1.7~22.4 wt% NaCl (avg. 10.2 wt% NaCl) | • 112~272 ℃ (avg. 187 ℃) • 0.5~34.1 wt% NaCl (avg. 14.5 wt% NaCl) |
Chlorite geothermometer | • 137~293 ℃ (avg. 228 ℃) | • 159~307 ℃ (avg. 212 ℃) |
Pressure | • < 3.16 kb | • < 3.62 kb |
Oxygen-carbon isotope | • δ18O: magnesite (9.2~16.9 ‰), dolomite (16.4~19.5 ‰) • δ13C: magnesite (-1.3~0.9 ‰), dolomiticmarble (0.6~1.4 ‰) | • δ18O: magnesite (8.7~11.4 ‰), dolomite (19.0~23.0 ‰) • δ13C: magnesite (0.1~0.8 ‰), dolomite (-0.95~1.0 ‰) |
References | This study, Tang | Lee |
Sunjin Lee, Sang-Hoon Choi
Econ. Environ. Geol. 2021; 54(6): 753-765Sunjin Lee, Sang-Hoon Choi
Econ. Environ. Geol. 2021; 54(1): 49-60Sol Park, Jung Hun Seo, Chang Seong Kim, Yoon-Seok Yang, Jihye Oh and Jonguk Kim
Econ. Environ. Geol. 2020; 53(3): 221-234