Pronounced and rapid exhumation of the Connecticut Valley Trough revealed through quartz in garnet Raman barometry and diffusion modelling of garnet dissolution–reprecipitation reactions
Pronounced and rapid exhumation of the Connecticut Valley Trough revealed through quartz in garnet Raman barometry and diffusion modelling of garnet dissolution–reprecipitation reactions
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通过石榴石拉曼气压测定中的石英和石榴石溶解再沉淀反应的扩散模型揭示了康涅狄格河谷的明显和快速折返
DOI：
10.1111/jmg.12601
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发表时间：
2021
影响因子：
3.4
通讯作者：
Harrison, T. Mark
中科院分区：
文献类型：
--
作者：
Wolfe, Oliver M.;Spear, Frank S.;Harrison, T. Mark
对来自康涅狄格谷海槽(CVT)、佛蒙特州和马萨诸塞州的变质岩进行了石英石(QUIG)和常规温压测量、热力学反应模拟、扩散模拟和40Ar/39Ar热年代学研究，以确定它们在阿卡迪亚变质作用和随后的折返过程中的p-T-t轨迹。在阿卡迪亚穹隆附近采集的大量样品中，含有石榴石斑岩，显示出多云区，其特征是大量的流体包裹体和与原始石榴石被biotite±muscovite±plagioclase±quartz±lowXgrs/enrichedXsps.取代有关的修改的石榴石成分。Quig和常规的温压测量将石榴石的成核条件和峰值P-T条件都限制在~0.85-1.05 Gpa，~550-600°C之间。最值得注意的是，Quig压力测量结合Gibbs法反应模型对这些反应区附近的包裹体进行了测量，揭示了这些溶解-再沉淀反应发生在从峰值P-T条件到~0.3 Gpa，550°C附近的近等温减压过程中。扩散模拟表明，在石榴石再吸收过程中产生的Mn分带剖面在不到10℃的时间内形成。3 Ma，构造折返速度为8-1000万mm/年。随后以100°C/Ma的速度迅速冷却到500℃，然后缓慢冷却，到中石炭世达到1.7°C/Ma。这是首次报道的揭示多阶段变质历史的Quig气压法实例，并突出了该方法在解开复杂变质地体方面的实用价值。
Metamorphic rocks from the Connecticut Valley Trough (CVT), Vermont, and Massachusetts, have been examined using quartz‐in‐garnet (QuiG) and conventional thermobarometry, thermodynamic reaction modelling, diffusion modelling, and40Ar/39Ar thermochronology to constrain theirP–T–tpaths during Acadian metamorphism and subsequent exhumation. Numerous samples, collected in the vicinity of the Acadian domes, contain garnet porphyroblasts that display cloudy zones characterized by numerous fluid inclusions and modified garnet compositions associated with the replacement of the original garnet by biotite±muscovite±plagioclase±quartz±lowXgrs/enrichedXsps. QuiG and conventional thermobarometry constrain both the conditions of garnet nucleation and peakP–Tconditions to have occurred at ~0.85–1.05 GPa, ~550–600°C. Most notably, QuiG barometry was performed on inclusions adjacent to these reaction zones in conjunction with Gibbs method reaction modelling to reveal that these dissolution–reprecipitation reactions occurred during nearly isothermal decompression from the peakP–Tconditions to around ~0.3 GPa, 550°C. Diffusion modelling reveals that the Mn zoning profiles created during garnet resorption that accompanied decompression formed in less thanc. 3 Ma, which constrains the tectonic exhumation to have occurred at 8–10 mm/year. Subsequent cooling to 500°C occurred rapidly at a rate of 100°C/Ma, followed by slower cooling reaching 1.7°C /Ma by the mid Carboniferous. This is the first reported example of QuiG barometry revealing a multi‐stage metamorphic history and highlights the utility of this method for unravelling complex metamorphic terranes.
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影响因子：
3.9
作者：
F. Spear
通讯作者：
F. Spear
泥质片岩中石榴石成斑细胞的部分平衡及其对前变质作用的控制，格伦罗伊，苏格兰
影响因子：
3.4
作者：
T. Dempster;M. I. Gilmour;P. Chung
通讯作者：
P. Chung
美国新英格兰古生代造山带
影响因子：
1
作者：
P. Robinson;R. Tucker;D. Bradley;Henry N Berry Iv;P. Osberg
通讯作者：
P. Osberg
苏格兰东部泥岩相系列及达尔拉德变质作用的温度和压力
DOI：
10.1144/gsl.sp.1979.008.01.36
发表时间：
1979
期刊：
Geological Society, London, Special Publications
影响因子：
--
作者：
B. Harte;N. Hudson
通讯作者：
N. Hudson
希腊锡弗诺斯岛蓝片岩单元的反应超越和峰值 P-T 条件的重新评估：对基克拉泽斯俯冲带的影响
影响因子：
2.6
作者：
Castro, Adrian E.;Spear, Frank S.
通讯作者：
Spear, Frank S.