Not exactly. There’s no sign that they are currently growing, but they may have simply formed more recently. The interesting thing about plate tectonics, is that it was theorized sometime in the 1960’s. I only bring this up to convey how youthful our knowledge of the Earth’s crust is. A great example of this is the Rocky Mountains. They are in fact growing still, but geologists are somewhat puzzled as to why. Mainly because they are so far away from the compressional forces of plate activity. I’ll be discussing this in a future post so stay tuned!