In geology, "terranes" are discrete layers of the planet's crust representing different epochs and regions that have been commingled by geological forces. When multiple terranes collide, they result in a superterrane.
I think about this concept often as I observe the constant shift and churn of my urban environment.
Sleeping Phoenix
Core Sample, Franklin
Veil
Core Sample, Selby
Huff, Puff
Interchanging
Range