激光诱导击穿光谱判定岩石陆相和海相沉积

Determination of Terrestrial and Marine Sedimentary Rocks by Laser-induced Breakdown Spectroscopy

研究了激光诱导击穿光谱技术在判别未经预处理岩石样品沉积相方面的识别能力.将经地质专家鉴定的27个陆相和14个海相沉积样品作为待分析样品,B的谱线强度及B/Ga、Sr/Ba和Fe/Mn谱线的积分强度比分别作为区分依据用于判别沉积相.由于B、Ga、Sr和Ba在岩石中含量非常低,而且分布不均,导致少量样品难以区分.Fe和Mn的含量相对较高,因此Fe/Mn能够很好地将陆相和海相沉积样品区分.相对于其它区分依据,Fe II 259.940nm/Mn II 259.372nm表现出最好的区分性能.激光诱导击穿光谱技术能够实现录井现场快速、准确判别岩石样品沉积相.

This paper mainly investigates the ability of laser-induced breakdown spectroscopy to discriminate the sedimentary facies of untreated rock samples. Twenty-seven continental and 14 marine sediment samples identified by geologists were used as samples to be analyzed. The line intensity of B, the integral intensity ratio of B/Ga, Sr/Ba, and Fe/Mn lines are used as the discrimination basis for discriminating the deposition phase. Because B, Ga, Sr, and Ba are very low in the rock and are not evenly distributed, a small amount of sample is difficult to distinguish. The content of Fe and Mn is relatively high, so Fe/Mn can distinguish the terrestrial and marine sediment samples well Overall, the best distinguishing performance was exhibited with respect to other discrimination based on FeⅡ 259.940 nm/Mn Ⅱ 259.372 nm. The results show that laser induced breakdown spectroscopy can quickly and accurately discriminate the sedimentary facies of rock samples at the logging site.