Thermo-Tectonic Implications of Zircon and Apatite FT Data of the Marlborough Region, South Island, New Zealand

紐西蘭南島馬博羅地區鋯石與磷灰石核飛跡資料其地質熱歷史與地體構造史之意義.

高銘鴻(Ming-Hung Kao)

《Terrestrial, Atmospheric and Oceanic Sciences》 13卷2期 (2002/06) Pp. 109-124

並列摘要

Zircon and apatite fission track (FT) reveal some of the thermo-tee- tonic features of the Marlborough Region, South Island, New Zealand. The very young FT ages (＜10 Ma) of zircon and apatite in the vicinity of the Alpine Fault bend and Seaward Kaikoura Range coincide with the recent rapid uplift/erosion. Four samples with reset zircon ages in the Alpine Fault bend reveal that the host rocks in this area cooled below the closure termperature of zircon (~240℃) in the late Miocene. Unlike these four zircon FT ages, most zircon FT ages are consistent with depositional ages. Annealed apatite and unannealed zircon FT ages show that the Marlborough did not experience exposure to the closure temperature of zone (PAZ) of apatite (~60-100℃). The host rocks in the north rather than those in the south passed through the lower part of apatite PAZ. In addition, most of the zircon samples with low P( X2) values (＜5 %) show that the samples have been slightly annealed, implying that the host rocks might have experienced the upper part of the partial annealing zone of zircon (~175℃) during the Mesozoic cooling.

並列關鍵字

FT analysis ； Tectonics ； Closure temperature