The southern side of the complex shows some traces of past glaciation in the form of two different sets of apron-like moraines, one at an elevation of and the other at ; even lower moraines have been found and valley glaciers formed on Paruma. Some lower lava flows show evidence of heavy glaciation. At least one warm spring is located at the foot of Olca-Paruma. The eastern slopes drain into the Salar de Laguani, the northern slopes into the Salar de la Laguna, and the southwestern slopes into the Salar Michincha. On the southeastern side the Rio Pajancha originates on Olca-Paruma's slopes, while the southern slope drains into the Salar de Alconcha through the Quebrada Churchicha and Quebrada Juchuchurchicha.