Methylated 2-methyl-2-(4,8,12-trimethyltridecyl)chromans are salinity-sensitive biomarkers that have been detected in immature – early mature petroleum and sediments. In this study, the occurrence and distribution patterns of 2-methyl-2-(4,8,12-trimethyltridecyl)chromans were investigated in a set of lacustrine sediments from Nördlinger Ries of southern Germany and marine sediments from the South China Sea. Among all of the 2-methyl-2-(4,8,12-trimethyltridecyl)chroman isomers detected, 8-Me-2-methyl-2-(4,8,12-trimethyltridecyl)chroman presented with high abundance in sediments deposited in hypersaline environments, while absent in samples from normal marine environments. In contrast, 5,7,8-triMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman was more enriched in sediments from marine environments. This study also showed that the ratio of 5,7,8-triMe-/5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman can be applied as a potential salinity indicator on account of a positive correlation with other 2-methyl-2-(4,8,12-trimethyltridecyl)chroman salinity indicators. This ratio can be an alternative indicator of paleosalinity when 8-Me-2-methyl-2-(4,8,12-trimethyltridecyl)chroman is absent or present in quite low abundance. The content of 2-methyl-2-(4,8,12-trimethyltridecyl)chroman isomers may be affected by freshwater supply and lithology. Molecular simulations showed that 5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman has a higher thermal dynamic stability than 7,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman. Thus, the ratio of 5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman/7,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman may be a potential maturity parameter for sediments at a low thermal mature stage.

甲基化 2-methyl-2-(4,8,12-trimethyltridecyl)chromans 是盐度敏感的生物标志物，已在未成熟的早期成熟石油和沉积物中检测到。在本研究中，研究了德国南部 Nördlinger Ries 湖相沉积物和南海海洋沉积物中 2-methyl-2-(4,8,12-trimethyltridecyl)chromans 的发生和分布模式。在所有检测到的 2-methyl-2-(4,8,12-trimethyltridecyl)chroman 异构体中，8-Me-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 在沉积沉积物中的丰度很高在高盐度环境中，而在正常海洋环境的样本中不存在。相比之下，5,7,8-triMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 在海洋环境的沉积物中含量更高。该研究还表明，5,7、8-triMe-/5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 由于与其他 2-methyl-2-( 4,8,12-三甲基十三烷基）色满盐度指示剂。当 8-Me-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 不存在或以非常低的丰度存在时，该比率可以作为古盐度的替代指标。2-甲基-2-(4,8,12-三甲基十三烷基)色满异构体的含量可能受淡水供应和岩性影响。分子模拟表明，5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 比 7,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman 具有更高的热动态稳定性。 12-三甲基十三烷基）色满。因此，5,8-diMe-2-methyl-2-(4,8,12-trimethyltridecyl)chroman/7,8-diMe-2-methyl-2-(4,8,