Extent and limits of biodegradation by in situ methanogenic consortia in shale and formation fluids

► Labile organic compounds in New Albany Shale fluids suggest limited biodegradation. ► Low biodegradation indices in core samples also indicate limited biodegradation. ► The New Albany Shale is less biodegraded than similar microbial methane reservoirs. ► Enhancing CH4 production may entail stimulating microbial consortia and methanogens.