Lagoa do Fogo - Açores, Portugal
Posted by: 
RuiJSDuarte
N 37° 45.754 W 025° 29.514
26S E 632836 N 4180542
"Lagoa do Fogo is a crater lake within the Agua de Pau stratovolcano in the center of the island of São Miguel Island in the Azores."
Waymark Code: WMKF7J
Location: Arquipélago dos Açores, Portugal
Date Posted: 04/05/2014
Views: 15
"This Lagoon is also the highest lagoon in the island, since it is part of a mountain with its highest point at 949 meters. The lagoon, being in the center of the crater, is at a lower quota, around 575 meters. The maximum water depth in this lagoon is 30 meters. The walls in the caldera can reach unevenness's of 300 meters.
Agua de Pau stratovolcano in central Sao Miguel Island contains an outer 4 x 7 km caldera formed about 30,000 to 45,000 years ago and an inner 2.5 x 3 km caldera that was created about 15,000 years ago.
The younger caldera is partially filled by the Lagoa do Fogo caldera lake. Several post-caldera lava domes were emplaced on the northern and western flanks of the volcano, but activity in the caldera did not resume until about 5000 years ago.
The 3-cu-km Fogo - A plinian pumice-fall deposit, the product of the largest-known Holocene eruption in the Azores, was emplaced at this time. Numerous flank cinder cones mark radial and concentric fissures, some of which have been active during historical time.
The latest trachytic explosive eruption took place during 1563. Prominent hot springs are located on the NW flank.
This lagoon is the main water source, in S. Miguel. Other lagoons in the island have contamination problems, due to the massive use of agricultural fertilizers rich in nitrogen. The fact that the lands in the Lagoon area are not very suitable for cultures or pastures, is a big advantage.
Also, the governmental authorities do not allow any modern construction around this lake."
The description is from this great cache - (
visit link)