Abstract The Upper Yangtze Craton (UYC) has stayed in a long-term stabilization state. Its thermal history can be portioned into two parts: secular evolutionary trend and short-lived thermal perturbations. The former is simulated by a two-dimensional forward transient thermal model, and the latter is discussed by reviewing previous studies. The numerical modeling indicates the UYC tended to be cooling as it adjusted to the asynchronous rates of change in the internal radiogenic heat production and in the convecting mantle temperature below the cratonic root. The average cooling rate of the UYC has been ~58 °C/Ga since the end of Archean, faster than that of the convecting mantle. The surface heat flow presents a decreasing trend from ~82 mW/m2 at 2.5 Ga to ~53 mW/m2 at present-day, which constructs the long-term evolutionary path. The thermal perturbations derived from the occasional tectono-thermal events, such as mantle plume activity and regional lithosphere extension, serves as paroxysmal factors. The thermal effects of the Emeishan mantle plume were very strong, yielding to the maximum heat flow anomaly of ~100 mW/m2 at the Late Permian. In contrast, the influences of regional lithosphere extension during both the early Paleozoic period and the Early Permian-Middle Triassic period were rather weak, resulting in a surface heat flow increase of

中文翻译：

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上扬子克拉通的热演化：长期冷却和短暂的热扰动

摘要 上扬子克拉通（UYC）长期处于稳定状态。它的热历史可以分为两部分：长期演化趋势和短期热扰动。前者通过二维正向瞬态热模型进行模拟，后者通过回顾以前的研究进行讨论。数值模拟表明 UYC 趋于冷却，因为它适应了内部辐射热产生和克拉通根部以下对流地幔温度的异步变化率。自太古代末期以来，UYC 的平均冷却速度约为 58 °C/Ga，快于对流地幔的冷却速度。地表热流呈现出从 2.5 Ga 时的~82 mW/m2 到目前的~53 mW/m2 的下降趋势，构建了长期演化路径。由偶然的构造热事件（例如地幔柱活动和区域岩石圈扩展）引起的热扰动是突发性因素。峨眉山地幔柱的热效应非常强，在晚二叠世产生了~100 mW/m2的最大热流异常。相比之下，早古生代和早二叠世-中三叠世区域岩石圈伸展的影响较弱，导致地表热流增加