Value: B Label: Boundary stratotype (B): If a unit does not have a documented locality where both its base and its main body are sufficiently represented, the type locality for the lower boundary is defined by the boundary stratotype. Description: Symbol:
Value: U Label: Unit stratotype (U): If a unit does not have a documented locality where both its base and its main body are sufficiently represented, the type locality for the main body is defined by the unit stratotype. Description: Symbol: