Pasadena orogeny Pasadena orogeny Pasadena orogeny is a mountain building event. Conventionally it refers to the formation of mountains in mainly Southern California during the Pleistocene and lasting until the present day; originally it referred to the uplift of the San Gabriel Mountains. The Pasadena orogeny is a major Late Quaternary-modern event of mountain formation, which took place in the middle or perhaps late Pleistocene or to the present-day. It is also known as the "Coast Ranges orogeny" or considered to be part of the Cascadian orogeny or Alpide Orogeny. Finally, the term "Pasadena orogeny" is sometimes applied to all very recent
Colorado orogeny Central Plains orogeny. The boundary between the Colorado orogeny and the Wyoming craton is the Cheyenne belt, a 5-km-wide mylonitic shear zone that verges northward. The Cheyenne belt transects and cuts off the south edge of the older Trans-Hudson orogeny. The Paleoproterozoic volcanic and sedimentary rocks that resulted from the Colorado orogeny underwent metamorphism followed by plastic folding under moderate pressure and temperature (PT) conditions (temperature about 500 °C and pressures in excess of 1.2 GPa). The metamorphism was accompanied by intrusion of intermediate calc-alkalic rocks, such as the granodiorites of the Boulder Creek batholith. The accompanying amphibolite facies metamorphism