自生（authigenic）矿物或沉积岩的矿藏为那些在发现的地方制造的沉积物。自生沉积物可以利用作描绘变质矿物经历变质作用（metamorphism）时或沉积矿物经历沉积作用（sedimentation）（如沉淀或再结晶作用（recrystallization））的特性，而非由风或水等经别处运送至此。自生沉积作用为其中一种主要的深海沉积作用。

An authigenic mineral or sedimentary rock deposit is one that was generated where it is found or observed. Authigenic sedimentary minerals form during sedimentation by precipitation or recrystallization instead of being transported from elsewhere (allogenic) by water or wind. Authigenic sediments are the main constituents of deep sea sedimentation. Authigenic clays tend to reduce the porosity of sediments, thus reducing permeability.