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To date, very little has been published on the organic geochemical and petrological aspects of the Bara formation coals, Southern Indus Basin, Pakistan. To address this, fresh unweathered coal samples were collected from seven different coal mines of the Lakhra coal field and were subsequently analysed and evaluated in detail. Numerous characteristics were assessed i.e. thermal maturity (coal rank), petroleum generation potential, type of organic matter and paleo-depositional environment. Evaluation techniques include proximate analysis, bitumen (soluble organic matter) extraction, fractionation of hydrocarbon yield using liquid column chromatography, Rock Eval, pyrolysis-GC (Py-GC), GC-MS, huminite/vitrinite reflectance and maceral analysis. Based on proximate analysis, the samples are classified as lignite to subbituminous C based on the ASTM standard. This low rank is supported by extracted bitumen and Rock Eval data. Although immature, these Lakhra coals show to possess excellent hydrocarbon generation potential. The distributions of n-alkanes, isoprenoid, hopane and sterane biomarkers further corroborate that these coals are thermally immature for hydrocarbon generation. The probable paleodepositional environment interpreted based on biomarkers and maceral analysis data suggests a waterlogged swamp in a lower delta plain setting that experienced frequent marine influence as indicated by the sub-oxic condition of deposition. [ABSTRACT FROM AUTHOR]