40Ar-39Ar同位素定年方法研究进展

^40Ar-^39Ar同位素定年法是由K-Ar法发展而来,通过将39K利用快中子辐照衰变成^39Ar,测量40Ar^＊/^39Ar来获得年龄值.经过长期发展,该方法的测试技术逐渐成熟,其中气体提取发展为常规阶段升温法、激光显微探针法以及真空压碎流体包裹体法；气体纯化主要有冷阱去除法、钛泵吸附法、锆铝泵吸附法；气体测试的质谱仪也在灵敏度、分辨率、背景值等技术指标上有很大提高.^40Ar-^39Ar同位素定年法在石油、固体矿产等方面应用广泛,尤其在油气成藏时间、成岩成矿作用时间的热年代学研究等领域.

Advances in the study of 40Ar-39Ar isotopic dating method

^40Ar-^39Ar isotopic dating method is developed from K-Ar method which irradiate ^39K into ^39Ar by fast neutron and measure ^40Ar^＊/^39Ar to get the age value. After a long-term development, testing technologies of this method is matured, gas extraction stage has been developed into the conventional step-heating method, laser microprobe law as well as fluid inclusions vacuum crushing method. Gas purification methods mainly contain cold trap removal method, titanium pump adsorption method and zirconium-aluminum pump adsorption method. For gas testing, some technical indicators of mass spectrometers have greatly improved, especially in sensitivity, resolution, background. ^40Ar-^39Ar isotopic dating method is widely applied in the fields of petroleum, solid minerals, etc., especially in thermochronology for hydrocarbon accumulation time, diagenetic time, mineralization time.