The sedimentary sequence of Barail Group preserves the records of depositional history of Indo-Myanmar Range during Eocene-Oligocene. Field investigation, geochemistry and detrital geochronology are used to study its geochemical characteristics, sediment provenance and tectonic setting. Major elements based discrimination plots indicate sediments of this group are derived from quartzose sedimentary sources and deposited in a passive margin tectonic set-up.Barail sandstone display a gentle sloping LREE and more or less at HREE pattern, and show negative Eu anomaly and positive Sm anomaly. Detrital zircon U-

The sedimentary sequence of Barail Group preserves the records of depositional history of Indo-Myanmar Range during Eocene-Oligocene. Field investigation, geochemistry and detrital geochronology are used to study its geochemical characteristics, sediment provenance and tectonic setting. Major elements based discrimination plots indicate sediments of this group are derived from quartzose sedimentary sources and deposited in a passive margin tectonic set-up. Barail sandstone display a gentle sloping LREE and more or less flat HREE pattern, and show negative Eu anomaly and positive Sm anomaly. Detrital zircon U-Pb reveal age ranging from 3225 Ma to 90 Ma, with clusters at222–90 Ma, 1215 − 394 Ma, 1849 − 1364 Ma, 2500–2094 Ma and 3225–2094 Ma. These results indicate majority of the sediments of the Barail Group were sourced from the Tethyan Sedimentary Sequence and Trans-Himalayan granitoids and deposited in shallow marine condition to deltaic environment.