Formation mechanism of Gongchangling high-grade magnetite deposit hosted in Archean BIF, Anshan-Benxi area, Northeastern China

Spectral Alteration Zonation Based on Close Range HySpex-320 m Imaging Spectroscopy: A Case Study in the Gongchangling High-Grade Iron Ore Deposit, Liaoning Province, NE China

“…The combination of traditional and spectral alteration zones can better indicate the regular change of alteration rock during mineralization. In Gongchangling deposit, magnetite mineralization and wall rock alterations are consistent in both time and space, and each are relatively reductive environments, which was revealed by the HySpex spectrum data and results of traditional geological methods and is in consistent with the previous studies, including fluid inclusions, whole rock geochemistry analysis and rare earth trace elements analysis [27,29,36,40]. Hence, the alteration zonation results according to the HySpex spectrum are credible.…”

“…Previous studies have focused on the origins of high-grade iron ore, and the major opinion accepted by most scholars is that the magnetite quartzite is modified to form high-grade iron ore by a hydrothermal solution, accompanied by chlorite, garnet and other altered minerals [28][29][30][31]. At present, the source of hydrothermal fluid is argued as either hydrothermal from magma [32,33], or the metamorphic hydrothermal fluid in the regional metamorphism process [34][35][36][37]. Anyway, there are hydrothermal (gas) altered rocks around the high-grade iron ore.…”

In-situ LA-ICP-MS trace elemental analyses of magnetite: Cu-(Au, Fe) deposits in the Khetri copper belt in Rajasthan Province, NW India

“…Another explanation is that the original BIF-type magnetite grains have precipitated from extremely Al-Tirich water compared to those in Yilgarn and Labrador. There is a common consensus that the formation of most BIFs has involved submarine volcano-derived hydrothermal fluids (e.g., Lascelles, 2007;Wang et al, 2014), and thus the high Al, Ti and even Ni contents of the originally BIF-type magnetite in the Khetri belt may be related to hydrothermal fluids derived from relatively mafic submarine volcanic rocks (c.f., Carew, 2004). Such a conclusion is also supported by the association of the magnetite-quartzites with mafic volcanic layers (now amphibolite) in the Delhi Supergroup.…”

Types and geological characteristics of iron deposits in China

“…(6) Gongchangling-subtype: High-grade iron deposits developed from the hydrothermal replacement and alteration of older Anshan-subtype iron deposits. These are represented by the mining area II of the Gongchangling iron deposit in Liaoning Province (Li et al, 2012b;Yang et al, 2012;Wang et al, 2014;Sun et al, 2014a). …”