The origin of trimethyldibenzothiophenes and their application as maturity indicators in sediments from the Liaohe Basin, East China

- Trimethyldibenzothiophenes have product-precursor links with trimethylbiphenyls in sediments.
- A new maturity parameter 2,4,6-/(2,4,7 + 2,4,8)-trimethyldibenzothiophene is proposed.
- This ratio shows a regular increase with the increasing maturity within oil generation window.
- It shows a reverse changing trend with increasing maturity in low maturity stages.