The Alps were formed by the collision of the Adriatic and European continents and the collision is still underway, with convergence rates of less than . This convergence causes rock uplift and earthquake activity. The western and central Swiss Alps are the fastest rising region of the country, with uplift rates of reached near Brig. A number of recently active fault systems have been identified in the Western Alps, but they often show only subtle signs of movement. Additionally, many faults are caused by gravitational phenomena rather than tectonic processes but the Gemmi Fault is undoubtedly of tectonic origin.