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在亚利桑那州南部Picaho变质核杂岩内的第三纪地壳滑脱断层的构造剖面上,展示了三个构造层.自下而上分为未遭受变形的花岗岩基底、糜稜岩化层和角砾状、热液蚀变层.底部滑脱断层构成了下层的顶面,并伴有糜稜岩和绿泥石角砾岩;其上为蚀变程度不均的碎裂花岗岩中层,中层的顶部为上滑脱断层,其面上叠加了中新世外来的强烈氧化及钾化的火山岩.在这个过程中,δ~(18)O增加了10‰.,温度下降了400℃.下层未变形的Oracle花岗岩(δ~(18)O≈7.8)保留了似岩浆岩的矿物分馏特征,但在环境温度约为520℃,δ~(18)O_(H2O)≈4‰的水与岩石低比率占主导的情况下,这种分馏在温度下降300℃,以及在水与岩石高比率的条件下,δ~(18)O_(H2O)=3‰±1‰的流体渗入时,绿泥石化角砾岩记录了全岩变化值为+8‰.在强烈氧化和钾交代的上层火山岩温度下降到150℃时,上滑脱断层为一明显的同位素不连续面.下部的两个层和上层的蚀变作用分别与两个不同的流体层有关.在构造剖面上自下而上地记录了温度从高到低、水与岩石的比率从低到高、并以塑性蠕变到脆性破裂的变化规律,以及展示了深部“交换”流体与浅部表层氧化含水层之间的界面.
Three tectonic strata are shown on the tectonic section of the Tertiary crustal slip faults within the Picaho metamorphic core complex in southern Arizona, dividing into bottom-up granite basement, mylonitized rock and brecciated and hot Hydrothermal alteration layer.The bottom detachment fault forms the top surface of the lower layer, accompanied by mylonites and chlorite breccias; the middle of which is the middle layer of fractured granite with uneven alteration, In the process, strong oxidation and potassic volcanic rocks were superimposed on the surface, and the δ 18 O increased by 10 ‰ and the temperature dropped by 400 ° C. The undeformed green granite (δ ~ 18) O≈7.8) retained the mineral fractionation characteristics of magmatic rocks. However, under the condition that the water temperature is about 520 ℃ and the ratio of δ 18 O 2 H2O ≈ 4 ‰ is dominated by the low ratio of water to rock, Fractionation During the temperature drop of 300 ℃ and the infiltration of δ 18 O 2 H2O = 3 ‰ ± 1 ‰ under the condition of high ratio of water to rock, the chlorite breccia records the changes of the whole rock The value is +8 ‰. In the upper volcanic rocks strongly oxidized and potassium met the temperature dropped to 150 ℃, the up-slip fault is a significant isotope Discontinuities. The lower two layers and the upper alteration are related to two different fluid layers, respectively, from top to bottom in the tectonic profile, from high to low and water to rock ratios from low to high High and varies from plastic creep to brittle fracture and shows the interface between the deep “exchange ” fluid and the shallow surface aquifer.