Thermoelectric Characteristics of Pyrite from the Fengning Ag Polymetallic Deposit, Hebei Province and Its Implications

doi:10.19657/j.geoscience.1000-8527.2022.063

Abstract

Abstract:

The Fengning Ag polymetallic deposit is one of the most important Ag polymetallic deposits located in northern Hebei metallogenic area, north margin of North China Craton. In order to better explore the genesis of the deposit and make predictions for deep and peripheral mineralization of the mining area, the thermoelectric typomorphism of pyrite in different mineralization stages of the Niujuan Ag (Au) mining area of the Fengning Ag polymetallic deposit was studied. The results show that the pyrite thermoelectric coefficient ranges from 26-367 μV·℃^-1, mainly in the range of 200-330 μV·℃^-1. The pyrite thermoelectric conductivity type is all P type, and the average value of thermoelectric coefficient is 267 μV·℃^-1. The gradient of thermoelectric coefficient is 0.74 μV·℃^-1·m^-1 in the vertical space of about 80 m from 1,190 m depth to 1,110 m depth. In summary, only the shallow ore body has been disclosed in the Niujuan silver (gold) mining area, and the deep ore body has not been disclosed, and the erosion of the ore body is shallow, so there is a great prospect for deep ore prospecting. In addition, the pyrite formation temperature ranges from 147 ℃ to 281 ℃, mainly concentrated in 180 ℃ to 280 ℃, which is basically consistent with the variation range of fluid inclusion homogenization temperature measurement results, indicating that this deposit is a medium-low temperature deposit.

Key words: Fengning, Hebei Province, Ag polymetallic deposit, pyrite, thermoelectric, ore-forming temperature

CLC Number:

LI Yujie, LI Shengrong, YUAN Maowen. Thermoelectric Characteristics of Pyrite from the Fengning Ag Polymetallic Deposit, Hebei Province and Its Implications[J]. Geoscience, 2023, 37(02): 463-474.

Figures/Tables 13

Fig.1 Sketch map of the North China Craton showing the distribution of silver-polymetallic deposits((a), modified after Santosh et al. [10] and Li et al. [11]) and regional geological map of the North Hebei showing the distribution of silver-polymetallic deposits ((b), modified after Yang [12])

Fig.2 Regional geological map of the Fengning Ag polymetallic deposit ((a), modified after Li et al. [7]) and geological map of the Ag polymetallic deposit ((b), modified from Shen et al. [13])

Fig.3 Profile map of No.79 prospecting line in the Niujuan Ag (Au) mining area (modified from Shen et al. [15])

Fig.4 Structures of ores from the Niujuan Ag (Au) mining area

Fig.5 Ore texture of the Niujuan Ag (Au) mining area

Fig.6 Photographs showing the characteristics of the mineralizing stages at the Niujuan Ag (Au) mining area

Table 1 Thermoelectric coefficients of pyrites from the Niujuan Ag (Au) mining area

样号	成矿阶段	标高(m)	P型热电系数α (μV·℃^-1)			P型出现率(%)	N型热电系数α (μV·℃^-1)			N型出现率(%)
样号	成矿阶段	标高(m)	最大值	最小值	平均值	P型出现率(%)	最大值	最小值	平均值	N型出现率(%)
9-71-5	黄铁矿-石英阶段	1190	343	183	291	100	-	-	-	-
9-73-5	黄铁矿-石英阶段	1190	344	210	297	100	-	-	-	-
9-76-6	多金属硫化物阶段	1190	347	182	294	100	-	-	-	-
9-77-6	多金属硫化物阶段	1190	336	152	282	100	-	-	-	-
5-71-4	多金属硫化物阶段	1150	322	175	255	100	-	-	-	-
5-73-4	多金属硫化物阶段	1150	327	137	249	100	-	-	-	-
5-76-4	黄铁矿-石英阶段	1150	339	147	261	100	-	-	-	-
5-77-2	黄铁矿-石英阶段	1150	324	165	245	100	-	-	-	-
1-71-2	多金属硫化物阶段	1110	325	155	235	100	-	-	-	-
1-73-3	硅质岩阶段	1110	297	140	221	100	-	-	-	-
1-76-4	多金属硫化物阶段	1110	324	124	240	100	-	-	-	-
1-77-3	硅质岩阶段	1110	311	134	229	100	-	-	-	-
ZK76-9-10	黄铁矿-石英阶段	76-9号钻孔532 m	323	47	222	88	-12	-98	-47	12
ZK78-9-41	硅质岩阶段	78-9号钻孔651 m	320	37	175	88	-20	-179	-98	12
ZK76-9-23	多金属硫化物阶段	76-9号钻孔586 m	367	107	278	100	-	-	-	-
ZK74-6-13	硅质岩阶段	74-6号钻孔685 m	324	257	290	100	-	-	-	-
ZK74-6-7-2	黄铁矿-石英阶段	74-6号钻孔774 m	334	27	258	98	-94	-94	-94	2
ZK78-11-5	多金属硫化物阶段	78-11号钻孔944 m	342	200	276	100	-	-	-	-

Fig.7 Frequency histograms of thermoelectric coefficients of pyrites from different stages in the Niujuan Ag (Au) mining area

Fig.8 Frequency histograms of thermoelectric coefficients of pyrites from different levels in the Niujuan Ag (Au) mining area

Fig.9 Diagrammatic profile of vertical zoning of thermoelectric coefficients of pyrite in the Niujuan Ag (Au) mining area

Fig.10 Frequency histograms of the formation temperature of pyrites from different stages in the Niujuan Ag (Au) mining area

Table 2 Formation temperature of pyrites from different stages in the Niujuan Ag (Au) mining area

成矿阶段	形成温度(℃)
硅质岩阶段	153~260
黄铁矿-石英阶段	161~279
多金属硫化物阶段	147~281

Fig.11 Vertical longitudinal projection of thermoelectric coefficients of pyrites from the Niujuan Ag (Au) mining area

References 20

[1]	陈光远, 邵伟, 孙岱生. 胶东金矿成因矿物学与找矿[M]. 重庆: 重庆出版社, 1989:324-336.
[2]	李成禄, 李胜荣, 曲晖, 等. 山西繁峙义兴寨金矿黄铁矿成因矿物学特征及稳定同位素研究[J]. 矿物岩石, 2013, 33(1):1-7.
[3]	申俊峰, 李胜荣, 马广刚, 等. 玲珑金矿黄铁矿标型特征及其大纵深变化规律与找矿意义[J]. 地学前缘, 2013, 20(3):55-75.
[4]	李胜荣, 陈光远, 邵伟, 等. 胶东乳山金矿黄铁矿形态研究[J]. 地质找矿论丛, 1994, 1(9):79-86.
[5]	李胜荣, 陈光远, 邵伟, 等. 胶东乳山金矿田成因矿物学[M]. 北京: 地质出版社, 1996:1-95.
[6]	李青, 李胜荣, 张秀宝, 等. 河北省灵寿县西石门金矿黄铁矿热电性标型及其找矿意义[J]. 地质学报, 2013, 87(4):542-553.
[7]	李久明, 巩恩普, 姚玉增, 等. 冀北丰宁银(金)矿床地质、地球化学特征及成因[J]. 地质找矿论丛, 2006, 21(4):241-247.
[8]	翟明国. 华北克拉通2.1-1.7Ga地质事件群的分解和构造意义探讨[J]. 岩石学报, 2004, 20(6):42-53.
[9]	李江海, 钱祥麟, 黄雄南, 等. 华北陆块基底构造格局及早期大陆克拉通化过程[J]. 岩石学报, 2000, 16(1):1-10.
[10]	SANTOSH M, ZHAO D P, KUSKY T M. Mantle dynamics of the Paleoproterozoic North China Craton: A perspective based on seismic tomography[J]. Journal of Geodynamics, 2010, 49(1): 39-53. DOI URL
[11]	LI S R, SANTOSH M, ZHANG H F. Inhomogeneous lithospheric thinning in the central North China Craton: Zircon U-Pb and S-He-Ar isotopic record from magmatism and metallogeny in the Taihang Mountains[J]. Gondwana Research, 2013, 23(1): 141-160. DOI URL
[12]	杨仕道. 冀北银矿成矿地质特征及找矿预测[D]. 长沙: 中南大学, 2000.
[13]	沈利霞, 李文圣, 王自力, 等. 冀北牛圈银金矿及营房银铅锌矿深部成矿预测[J]. 地质找矿论丛, 2012, 27(4):450-457.
[14]	邵伟, 陈光远, 孙岱生. 黄铁矿热电性研究方法及其在胶东金矿的应用[J] .现代地质, 1990, 4(1):46-57.
[15]	HILL P A, GREEN R. Ther moelectricity and resistivity of pyrite from Renison Bell and MTB ischoff[J]. Tasmania Economic Geology, 1962, 57: 579-586.
[16]	卿敏, 韩先菊. 金矿床主要矿物标型特征研究综述[J]. 黄金地质, 2003, 9(4):39-45.
[17]	李红兵, 曾凡治. 金矿中的黄铁矿标型特征[J]. 地质找矿论丛, 2005, 20(3):199-203.
[18]	孟繁聪, 孙岱生. 山东烟台南张家金矿黄铁矿的标型特征[J]. 现代地质, 2001, 15(2):231-236.
[19]	邵洁涟. 伟晶岩矿床的找矿矿物学标志[J]. 地质地球化学, 1988, 1(1):1-3.
[20]	АНДРЕЕВ Б С. Пирит золоторудных месторождений[M]. Москва:И зд Наука, 1992:51-63.