Thermal properties of the hanging wall of the central Alpine Fault, New Zealand
Thermal properties of the hanging wall of the central Alpine Fault, New Zealand
复制标题
新西兰中部高山断层上盘的热特性
DOI：
10.1080/00288306.2020.1828939
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发表时间：
2020
影响因子：
2.2
通讯作者：
Lin Weiren
中科院分区：
文献类型：
--
作者：
Janku-Capova Lucie;Sutherland Rupert;Townend John;Lin Weiren
采用瞬态平面源测量了新西兰阿尔卑斯断层上盘的片岩、原糜棱岩、糜棱岩和超糜棱岩样品，得到室温下干燥状态下的平均体积热导率为2.04 ± 0.33 W m-1K-1，潮湿状态下的平均体积热导率为2.78 ± 0.51 W m-1K-1。相应的热扩散系数在干燥状态下为1.35 ± 0.32 × 10 - 6m2s-1，在湿润状态下为1.72 ± 0.27 × 10 - 6m2s-1。根据Whataroa Valley DFDP-2B钻孔岩屑的矿物组成和先前公布的矿物热性质计算的热导率和扩散率分别为3.26 ± 0.16 W m-1K-1和1.56 ± 0.08 × 10 - 6m2s-1。我们把热导率的显著差异归因于岩石样品与钻孔岩屑组成的区域矿物学变化。热性能的各向异性被推断存在于厘米尺度上，由于对齐的石英脉，矿物和微裂缝的竞争效应，但我们的测量并没有证实显着的各向异性。根据地球化学数据和DFDP-2B中的伽马测井数据计算的放射性生热率（1.8 - 2.1 μ W m-3）在先前报告的杂砂岩和片岩范围内。
Samples of schist, protomylonite, mylonite and ultramylonite from the hanging wall of New Zealand’s Alpine Fault were measured using a transient plane source, yielding mean bulk thermal conductivity of 2.04 ± 0.33 W m–1K–1in a dry state and 2.78 ± 0.51 W m–1K–1in a wet state at room temperature. Corresponding thermal diffusivity is 1.35 ± 0.32×10–6m2s–1in a dry state and 1.72 ± 0.27×10–6m2s–1in a wet state. Thermal conductivity and diffusivity calculated from the mineralogical composition of cuttings from the DFDP-2B borehole in Whataroa Valley and previously published thermal properties of minerals are 3.26 ± 0.16 W m–1K–1and 1.56 ± 0.08×10–6m2s–1, respectively. We attribute the significant difference in thermal conductivity to regional mineralogical variations in composition of rock samples versus borehole cuttings. Anisotropy of thermal properties is inferred to exist on a centimetre scale, due to competing effects of aligned quartz veins, minerals, and microfractures; but our measurements do not confirm significant anisotropy. Radiogenic heat productivity calculated from geochemical data and a gamma log in DFDP-2B (1.8–2.1 μW m–3) falls within the previously reported range for greywacke and schist.