基于太赫兹时域光谱技术的砂岩沉积作用模拟研究

Simulation of Sandstone Deposition Based on Terahertz Time Domain Spectroscopy

为模拟地质构造环境,选用石英砂颗粒作为模拟岩石的主要成分,与聚乙烯颗粒按一定比例混合后压片,并进行太赫兹光谱测试。实验发现质量分数为35%聚乙烯65%石英砂样品对太赫兹波的吸收随压力增加而增强,这与压力增大导致样品的密度增加有关,而50%聚乙烯50%石英砂样品对太赫兹波的吸收随压力增加先增强而后减弱,吸收减小与不同成分排列状况改变有关。实验表明,太赫兹光谱信息可以表征通常地质演化过程中随着埋深增加负荷加大而压实作用加强的过程,以及在特定的地质环境中,压实作用加强趋势受阻的过程。

In order to simulate actual geological formation,quartz sand grain and polythene grain are optioned to compress to tablet when mixed at specific ratio where quartz sand serves as a major component in rock but polythene serves as cement and pore,then experiment is performed using terahertz transmission spectroscopy.It is indicated that samples with 35% polythene and 65% quartz sand absorb terahertz wave in a greater degree when pressure rises and this phenomenon advents due to greater density of sample.However,absorption to terahertz wave rises at beginning period but decay at subsequent period in group of 50% polythene and 50% quartz sand.It is assumed that decrease of absorption has business with distribution of different grains.It turns out that information loaded by terahertz wave characterizes the process that enlarged burial depth cause greater load and greater compaction,and the process that at certain geological conditions the trend may be blocked.