胶砾岩（Plastiglomerate）是熔融后的塑胶与天然物质，如沙砾、贝壳、珊瑚碎片、木头等，冷却硬化后产生的岩石状物体。外观与砾岩相似，只是中间的胶结物成分为塑胶。

胶砾岩的形成主要是人为的高温下使塑胶废弃物熔化，例如营火、森林大火、燃烧垃圾，熔融的塑胶与环境中的其他物质结合所形成。由科学家在夏威夷发现并命名。

Plastiglomerate is a term that was proposed by Patricia Corcoran, Charles Moore and Kelly Jazvac for a stone that contains mixtures of sedimentary grains, and other natural debris (e.g. shells, wood) that is held together by hardened molten plastic. It has been considered a potential marker of the Anthropocene, an informal epoch of the Quaternary proposed by some social scientists, environmentalists, and geologists.