LEAD ISOTOPIC COMPOSITIONS OF NATIVE SULFUR CHIMNEYS FROM NEARBY KUEISHANTAO ISLAND IN NORTHEAST OF TAIWAN AND ITS GEOLOGICAL IMPLICATIONS
台湾东北部龟山岛附近海域自然硫烟囱体的铅同位素组成及地质意义

For determining the origin of the hydrothermal native sulfur chimney nearby Kueishantao Island, off the northeast Taiwan, geochemistry of lead isotope of native sulfur in the chimneys was studied. The result indicates that the lead isotopic composition is very homogeneous, indicative of a small field of the origin. However, the source of lead is different from those in deeper hydrothermal deposits. Moreover, the lead isotopic scope does not match with the Northern Hemisphere lead isotopic reference line (NHRL). Although the native sulfur chimney was from seawater, the seawater did not contribute the lead isotopics to the chimney-bearing lead but the continental crust did. Therefore, the continental crust beneath the island must have played an important role in material transfer and exchange during the formation of the chimney in the past geological history, which bears implication for understanding the regional complex geological structure and tectonic evolution.