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Modeling the elastic properties of organic shale has been of long-standing interest for source rocks and unconventional reservoir characterization.Organic shales exhibit significant variability in rock texture and reservoir properties at different maturity stages,and in turn will impart signatures on its elasticity.We propose a new rock physics modeling scheme honoring the maturity levels(immature,mature,and overmature),which are constrained by the evolution of the physical properties of organic shale upon kerogen maturation.In particular,at different maturity stages,the manners in which the compliant organic materials interact with the in-organic mineral matrix are characterized by different effective medium theories.On the basis of the developed rock physics templates(RPTs)for organic shale at immature,mature,and overmature stages,it is found that the elastic behaviors of organic shale have different performances at different maturity stages.Ignoring the impact of kerogen maturation is insufficient to adequately characterize the elasticity of whole organic shale system.Modeling results suggest that the elastic responses of organic shale are sensitive to two dominant factors-organic matter content and mineralogical composition.The elastic anisotropy characteristics are not only affected by the kerogen content and clay alignment,but also depend on the morphology of kerogen distribution.