海泡石形成机制及其在地质领域的应用进展OA

[Significance]Sepiolite is a clay mineral with a unique fibrous crystal structure;it has a significant po-tential application in the geological field due to its high adsorptive capacity and thermal stability.[Progress]The genesis types for sepiolite include direct deposition,terrestrial transport sedimentation and diagenetic alteration.Di-rect deposition is influenced by chemical conditions such as element concentration and pH.Terrestrial transport sedi-mentation is closely related to the geological environment and climatic conditions.Diagenetic alteration of sepiolite is affected by the burial depth and the properties of the hydrothermal fluids.Sepiolite is generally formed in an alkaline reducing environment rich in Mg and Si,but with a low Al content.During the thermodynamic evolution process,it undergoes mineral phase transitions and is transformed into minerals such as talc or montmorillonite,which imply different depositional and diagenetic evolutionary paths.In terms of geological applications,sepiolite has an excellent adsorptive behavior,and thus it can efficiently enrich organic matter,providing a basis for the formation of hydrocar-bon source rocks with significantly enhanced oil-and gas-generating potential and quality.The diagenetic fluids of the sepiolite layer help promote the transformation of high-energy beach limestone at the edge of a depression into a high-quality dolomite reservoir,thereby giving rise to either of two oil and gas accumulation models:self-generation and self-storage,or lower generation and greater storage.In addition,the thickness and distribution of sepiolite strata in-verts undulating paleolandforms and is also an effective indicator of oil and gas reservoir regions,thus providing an important basis for oil and gas exploration.In terms of paleoenvironment,the formation process of sepiolite also re-cords a range of information(e.g.,evaporation environment,water level changes,climate evolution and anoxic events)that can be used to reveal major geological events in the region.[Conclusions and prospects]Sepiolite has shown significant research value in oil and gas exploration,paleogeomorphic reconstruction and paleoenvironmental restoration.Future development trends of sepiolite will include its use in defining paleoenvironmental conditions,en-hancing the analytical ability of seismic data on the thickness of sepiolite strata,and developing the exploration of oil and gas in sepiolite strata.