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Doubt regarding Oil shale geology
Hi there, i just wanted a clarification regarding ""One theory supposes that the organic material in the Irati oil shale originates from algae deposited in a freshwater to brackish lacustrine environment""......In the above sentence, what does the phrase ""freshwater to brackish lacustrine environment"" mean??? Does it mean ""oil shale originates from algae deposited in a freshwater environment"" or does it mean ""oil shale originates from algae deposited in a brackish lacustrine environment"" ??? or does it mean something else???....  "