hal-00536576

jose _ burgos @ petroamazonas. ec ABSTRACT The geomorphological study by mean of remote sensing imagery of the Rio Pastaza Megafan (Ecuador and northern Peru), reveals the traces of numerous avulsions. 108 avulsion sites have been defined. The location of these sites, the available radiocarbon ages as well as historical maps of the 17th century, enable us to propose an evolution history of the migration and avulsions of the Rio Pastaza since the Last Glacial Maximum. The first avulsions of the Río Pastaza occurred after the LGM in a zone close to and roughly parallel to the sudandean front, where the developed avulsion gave a distributive pattern to the ancient stream of the Río Pastaza in an area located between the modern Río Morona and Pastaza, where they caused the Rio Pastaza to develop