R7: Petrology, Mineralogy and Economic geology (Joint Session with Society of Resource Geology)

[R7-04] Geology and iron mineralization in the Akatani skarn deposit, Shibata city, Niigata Prefecture.

*Kotaro Seno¹, Yasushi Watanabe¹, Takuya Echigo¹, Shogo Aoki¹ (1. Akita Univ.)

Keywords:Fe skarn deposit, hematite, magnetite, Ninoujidake Granite, magnetic susceptibility

The Akatani deposit is an iron skarn deposit, mainly composed of hematite. From the occurrence of the hematite ore bodies, this deposit has three epochs of formation; the Late Cretaceous Ninoujidake granite and Early Miocene dolerite and rhyolite. It is cleared that not only in each the theory proposed by preceding studies, but also in the new theory that secondary formation of magnetite after hematite formation. Therefore, it was concluded that this deposit formed a deposit rich in different types of hematite by redox reactions by multiple different mineralization.