1.1 本试验方法包括用显微镜测定沉积岩中分散的镜质组抛光表面在浸油中测得的反射率。该测试方法也可用于测定沉积岩中分散的镜质组以外的显微组分的反射率。 1.2 以国际单位制表示的数值应视为标准。本标准中不包括其他计量单位。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ===意义和用途====== 5.1 通过该测试方法确定的沉积岩中镜质组显微组分的平均反射率被用作热成熟度的指标，即在成岩、成岩和变质过程中经历的分散有机物质的渐进地球化学蚀变。就烃源岩而言，镜质组反射率定义了三大类热成熟度:未成熟( R o ran ≤ 0.5 %), 成熟的( R o ran ≈ 0.5 % 至1.35 %), 和过度成熟( R o ran ≥ 1.35 %) 关于液态碳氢化合物的生成，尽管并非所有从业者都同意这些热边界 ( 10 ) .由分散在沉积岩中的镜质组反射率确定的热成熟度与分类中给出的煤的等级分类相似 D388 并与《试验方法》中提出的煤中镜质组的反射率类似地进行测量 D2798 沉积岩中镜质组显微组分的平均反射率与地球化学确定的热成熟度参数相关，可用于表征热成熟史，校准埋藏史模型，并更好地了解常规和非常规石油系统中的生烃、运移和聚集过程。

1.1 This test method covers the microscopical determination of the reflectance measured in immersion oil of polished surfaces of vitrinite dispersed in sedimentary rocks. This test method can also be used to determine the reflectance of macerals other than vitrinite dispersed in sedimentary rocks. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The mean reflectance of the vitrinite maceral in sedimentary rocks as determined by this test method is used as an indicator of thermal maturity, that is, the progressive geochemical alteration of dispersed organic material experienced during diagenesis, catagenesis, and metagenesis. In the case of hydrocarbon source rocks, three major categories of thermal maturity are defined by vitrinite reflectance: immature ( R o ran ≤ 0.5 %), mature ( R o ran ≈ 0.5 % to 1.35 %), and overmature ( R o ran ≥ 1.35 %) with respect to the generation of liquid hydrocarbons, although not all practitioners agree on these thermal boundaries ( 10 ) . Thermal maturity as determined by the reflectance of vitrinite dispersed in sedimentary rocks is similar to the rank classification of coals as presented in Classification D388 and measured similarly to the reflectance of vitrinite in coal as presented in Test Method D2798 . The mean reflectance of the vitrinite maceral in sedimentary rocks correlates with geochemically determined parameters of thermal maturity and can be used to characterize thermal maturation history, to calibrate burial history models, and to better understand the processes of hydrocarbon generation, migration, and accumulation in conventional and unconventional petroleum systems.