Pine Canyon caldera complex

intrusion, which tends to mean a partial crustal boundary of the Ouachita orogeny. This feature represents the largest intrusion, (24–38 km (15–24 mi), 1–4 km (0.62–2.49 mi) thick, 700–3,000 km³ (170–720 cu mi) in volume) in an area where laccoliths are ubiquitous in nature. This intrusion may represent a long-lived magma chamber (1 m.y.) that was replenished by smaller batches of magma that varied in viscosity.^[1]