The Laguna Río Cuarto maar is at the northern end of a chain of vents extending to about 18 km from Poás volcano. The 600 x 750 m wide maar has a maximum depth of 66 m and the crater walls rise 4-20 m above the lake surface. The maar erupted through lahar and alluvial deposits on the coastal plain at an elevation of about 400 m above sea level.

Photo by Paul Kimberly, 1998 (Smithsonian Institution).

This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.

Keywords: maar | crater | crater lake

Poás