【摘要】 应用自行组装的激光诱导荧光显微光度计(LIFM)系统地研究了中国煤和烃源岩中镜质组的荧光强度及荧光变化,建立了镜质组的荧光变化与成熟度之间的相关模式图(R-I-VRo),该图可解决镜质组反射率抑制问题,并将烃源岩成熟度评价范围扩展到VRo达2.0%左右,该方法对于正确评价烃源岩成熟度具有广泛的应用前景。更多还原

【Abstract】 It is difficult to determine maturity of source rocks with vitrinite reflectance suppression and to obtain useful fluorescence information from coals and source rocks of high maturity by means of conventional fluorescence microscopy due to the low fluorescence intensity of the macerals. A laser induced fluorescence microscopy (LIFM) designed by the authors is applied to resolve the problem. An investigation is made by means of this technique on a suite of coals having a range of mean random vitrinite reflectance (VRo) of 0.37% ～ 2.0% . The results show that LIFM greatly improves several functions of conventional fluorescent microscopy. It is very sensitive to organic matter in sediments and for the suite of Chinese coals and source rocks investigated, considerably extends the maturity range over which visible fluorescence can be observed. The range is extended from about 1.25% to 2.0% VRo for vitrinite of normal composition. It is found that the primary fluorescence of vitrinite can be observed after the stages of VRo >0.50% , with positive alteration. On the basis of this, a R I VRo model is suggested, which is verified to be useful to determine thermal maturity of coal and source rocks with obvious vitrinite reflectance suppression.更多还原