摘要:电子自旋共振（ESR）是一种对断层物质、燧石、火山灰和沉积物（水系、风成、冰川）定年的重要方法，它广为接受的测年范围为第四纪。对断层泥和沉积物样品，石英ESR信号的不完全归零往往使ESR年龄偏老，多重ESR中心法和颗粒大小“平顶判据”是判断信号归零特征的两种有效方法。为将ESR测年范围拓展至前第四纪，通常采用石英氧空位在加热转化后极大增强的E’心作为测年信号，但由于石英氧空位形成转化机理不明确，加热后增强的ESR信号与地质年龄的相关性有待进一步验证。近期研究表明石英ESR的封闭温度为49 ℃～82 ℃，可在比磷灰石（U-Th）/He更低的温度区间内研究地球近地表的构造演化过程。释光技术热年代学研究发展迅速，与之测年原理接近的ESR在低温热年代学领域展现了良好的应用前景，它与释光及磷灰石（U-Th）/He可相互比对、共同提高地球近地表构造和地形演化问题的分析精度。
关键词: ESR/
第四纪/
前第四纪/
氧空位/
低温热年代学
Abstract:ESR has become an important method to fault gouge, flint, volcanic tephra and sediment （aqueous, aeolian or glacial） dating. The accepted dating range of ESR is limited to Quaternary era. For fault clay and sedimentary samples, the difficulty of ESR signals in quartz resetting to zero makes ESR ages often older than other dating techniques. While the “multiple centers” and “the grain size plateau” criterion are two effective ways to determine whether the ESR signals have reset to zero. In order to extend ESR dating range to pre-Quaternary, the enormously enhanced intensity of E’ signal which was transformed from oxygen vacancies by heating is often used. Since the formation and transformation mechanism of oxygen vacancies in quartz is not clear, the correlation between the increasing ESR signals after heating and the geological age needs to be validated. The closure temperature of quartz ESR is between 49 ℃～82 ℃, which is lower than apatite（U-Th）/He dating method. The quartz ESR can be used to study the tectonic evolution process in lower temperature range. In recent years, luminescence dating methods（including OSL and TL）develop quickly in thermochronology, which have similar principles with ESR. The ESR applications in low temperature thermochronometry show nice prospects. The corporation of ESR, luminescence and apatite（U-Th）/He dating can help to correct each other and enhance the analysis accuracy of tectonic and topographic evolution problems close to the earth surface.
Key words:ESR/
Quaternary/
Pre-Quaternary/
Oxygen vacancies/
Low temperature thermochronometry
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