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哀牢山-红河断裂带范围内样品热史演化的系统构建工作偏少;部分学者往往将样品的冷却年龄简单地归因于断裂带的事件年龄,而没有考虑热扰动因素,致使以往研究结论仍然存在分歧及不合理之处.利用断裂带中高温测年资料,构建了Tt变化曲线,结合压力-温度-深度(P-T-D)变化趋势及地层恢复,对T-t变化的成因提出了较为合理的解释.中高温热史演化表明断裂带SE端(大象山段)与NW端(哀牢山段)皆经历2期冷却过程;在地层剥蚀或构造剥露作用诱导下,SE端、NW端于32~30Ma、32~22Ma分别经历第1期冷却过程,而其在26~24Ma、22~20Ma分别经历的第2期冷却过程中,由于断裂活动减弱这一因素,致使该期冷却速率明显增大(尤其是断裂带NW端).伴随着印支地块的顺时针旋转挤出,断裂带中南部左旋转换拉张构造活动向北迁移.在断裂带T-t演化的第1个阶段内,受断裂带转换拉张强度NW向减弱的影响,断裂带SE端正断活动所致的山体隆升效应明显强于NW端,致使SE端样品冷却过程较早,同时冷却速率明显偏大;而在第2个阶段,伴随着青藏高原进入中新世早期的隆升阶段,作为高原东南缘板块调节边界的哀牢山-红河断裂带其活动性由SE端开始减弱,使得冷却过程由SE端向NW端传递.
Systematic construction of the thermal history evolution of samples in the Ailaoshan-Honghe fault zone is few; some scholars tend to simply attribute the sample cooling age to the event age of the fault without considering the thermal disturbance factors, leading to the conclusion of previous research There are still some disagreements and unreasonable points.Using the high-temperature dating data of the fault zone, the Tt curve is constructed, and the reason of the Tt change is reasonably explained by the change of pressure-temperature-depth (PTD) and the recovery of the formation . The evolution of the mid-high temperature and thermal history shows that both SE (Elephant Mountain) and NW (Ailao Mountain) faults undergo two stages of cooling process. Under the denudation of strata or structural tearing, the SE and NW ends are at 32 ~ 30Ma, 32 ~ 22Ma, respectively, experienced the first cooling process, and its 26 ~ 24Ma, 22 ~ 20Ma respectively through the second cooling process, due to the weakening of the fracture activity of this factor, resulting in a significant increase in the cooling rate (Especially the NW end of the fault zone) .At the same time as the Indosinian block rotates clockwise, the left-lateral transitional pull-tectonic movement in the south part of the fault zone migrates northward.In the first stage of the Tt evolution of the fault zone, With the conversion tensile strength NW weakened , The uplift effect of the mountain due to the normal faulting of the SE in the fault zone is obviously stronger than that of the NW end, leading to the earlier cooling of the sample in the SE end while the cooling rate is obviously larger. In the second stage, along with the Qinghai- In the early Eocene uplift stage, the Ailao-Honghe fault zone, which is the adjustment boundary of the southeastern margin of the plateau, begins to weaken from the SE side so that the cooling process is transmitted from the SE side to the NW side.