探索第四纪钻探岩心沉积物颜色测量新方法

A NEW METHOD FOR COLOR MEASUREMENT OF QUATERNARY DRILLING CORE DEPOSITS

文中提出1种基于数字图像分析法测量第四纪沉积物颜色的新方法,其操作简单快捷,可节省测试成本和时间,提高沉积物颜色研究效率。为论证该方法的可行性,对其测量成果同传统色度测量方法进行了对比。结果表明:1)传统沉积物颜色测量方法和数字图像颜色测量方法都受沉积物颗粒粒级制约。细砂及其以细颗粒可开展沉积物颜色研究,中砂、粗砂误差较大。同传统测量方法相比,数字图像法可减小粗碎屑沉积物颜色继承色干扰;2)碎屑沉积物粒级和含水量影响数字图像法沉积物颜色数值。一般来说,数字图像法获得的湿色数值低于使用分光测色仪所获得的干色数值,且颜色数值变化幅度更大,色度/亮度曲线表现出更大波状起伏;3)同传统沉积物颜色测量方法相比,数字图像法颜色测量红度、黄度具有较好一致性,而亮度受光照不均一影响,产生一定误差。采用沉积物数字图像提取沉积物颜色信息一定程度上可替代室内实测方法,用于建立更加复杂的沉积环境下较为完整的沉积物颜色序列,为第四纪地层划分、古气候研究、古土壤识别和古地震事件识别提供数据资料,拓展色度学在地质方向的应用。

In this paper,a method for measuring the color of Quaternary sediments based on digital image analysis is proposed,which has the advantages of simple and quick operation,and improving the research efficiency of sediment color.In order to demonstrate the feasibility of this method,the measurement results are compared with the traditional colorimetric measurement methods.The results show that:1)Both the traditional sediment color measurement method and the digital image color measurement method are controlled by sediment grain size.Sediment color research can be carried out on fine sand or finer sediments,but for medium grained sand and coarse sand,the error will be larger.Compared with the traditional measurement methods,digital image method can reduce the inherited color interference of coarse clastic sediments;2)The particle size and water content of clastic sediments affect the numerical value of digital image sediment color.Generally,the wet-color values obtained by the digital image method are lower than the dry-color values obtained by using a spectrophotometer,and the color value variation is large,and the undulation of chromaticity/brightness curve is greater;3)Compared with the traditional sediment color measurement method,digital image method has good consistency of color measurement of redness and yellowness,but the brightness is affected by uneven illumination,resulting in some error.Sediment digital image extraction of sediment color information can replace the indoor measurement method to a certain extent,and can be used to establish a more complete sediment color sequence under more complex sedimentary environment,so as to provide information for the Quaternary stratigraphic division,paleoclimate research,paleosol recognition and paleoearthquake event identification,thus expanding the application of colorimetric results to the geological direction.