太白山地域內 鑛床의 生成年齡

K-Ar ages of mineral deposits in the Taebaeg mountain district

K-Ar age determinations were carried out on muscovite and other gangue and wallrock alteration minerals from seventeen mineral deposits in the Taebaeg mountain district. Tin deposits give the ages of 1792 Ma and 158-127 Ma, whereas tungsten-molybdenum deposits give the ages of 1520-1480 Ma, 173-168 Ma and 84-81 Ma. Polymetallic mineral deposits, gold-silver deposits and sericite deposits yield the ages of 98-52 Ma, 93-75 Ma, and 202 Ma, respectively. Mineralization ages for each genetic type of deposits in this district can be summarized as follows ; pegmatite deposits, 1792 Ma ; pegmatite-hydrothermal deposits, 1526-1480 Ma ; greisen deposits, 157-127 Ma ; skarn deposits, 98-73 Ma and 52 Ma ; hydrothermal deposits, 202-168 Ma and 93-76 Ma. Present results together with data available in the literature reveal that five distinct mineralization ages can be recognized in this district ; (1) 1792 Ma, (2) 1526-1480 Ma, (3) 202-127 Ma, (4) 98-73 Ma, (5) 52 Ma. These age data are similar to the reported radiometric age data of igneous rocks in this district except for two ages such as 2154-2084 Ma and 880-738 Ma.