of
Valdivia River. Valdivia River empties to
Corral Bay in the Pacific Ocean. View of
Panguipulli Lake. Los Ríos Region lies in the southern
temperate zone and in a
tectonically active milieu. Four distinct landscape types, or morphological units, can be distinguished in the region. These are from west to east; the
Coastal Range, the
Intermediate Depression, the
Precordillera and the
Andes. These units are oriented parallel to the coast and the
subduction zone there. An exception to this are the eastern hills in
Mariquina and
Máfil that despite belonging to the Coast Range system adrift eastwards and comes very close to the Precordillera cutting the Intermediate Depression in two. The Coastal Cordillera does not exceed the 1000 m in height being
Cerro Oncol (715 m) the highest point in the
section north of Valdivia River. The Coast Range is cut by
Valdivia and
Bueno Rivers, deeply incised rivers that drains the inland. Most of the Coast is covered by native
Valdivian temperate rain forest, although it has in some parts been substituted by plantations of
exotic species, specially
Douglas firs and
eucalyptus. Two great agricultural flatlands exist in the region, the
Mariquina valley and
Los Llanos of
La Unión and
Río Bueno. The first one is a tectonic depression in the Coast Range connected to Valdivia by
Cruces River and the second is the continuation of the
Intermediate Depression that re-opens south of Máfil. The flatlands and mayor river valleys form large, open, cultural landscapes used as grassing
meadows or for growing crops. The Precordillera is a narrow band characterized by hosting a large number of deep
glacial piedmont lakes that are dammed by
moraines. These lakes intersect forested
granitic mountain massifs of up to 1500 m, such as
Cordillera Negra and
Cerros de Quimán.The Precordilleran hills and mountains have step slopes to the north and south as the main direction of the
Quaternary glaciers where from east to west. Many lake shores are cleared lands where agriculture, settlements and resort areas develop.
Andes The proper Andes extends from the eastern half of the Precordillean lakes to the border with
Neuquén Province in
Argentina. The Andes in this part of Chile, the
Zona Sur, has almost escaped the Andean
orogenesis. Here the Andes consist of old
granitic plutons such as the
Panguipulli Batholith and the
North Patagonian Batholith together with volcanics and some minor areas of sediments and
metasediments. As result of the minimal Andean mountainbuilding the mountains shows little rejuvenation and are mostly shaped by erosive agents, specially glaciers. An exception to this are the several volcanoes that rises east of the piedmont lakes, this volcanoes are among the most active in Chile and as result their form are influenced by the eruptions; either in constructive manner such as
Villarrica Volcano or more destructive like
Quetrupillán. The fact that these volcanoes have the ability to build up cones and rise again after erosion and explosive eruptions makes many of them the highest mountains in the region and
Zona Sur. The volcanoes of Los Ríos Regions belong to the
Southern Volcanic Zone of Andes, whose current activity front is located about 200 km west from the main Andean cordillera, this makes volcanoes stand out as isolated snow-covered cones of more than 2000 m, above the lower mountains that rarely pass the 1500 m. The main cordillera makes up the
continental divide and are therefore according to the
1881 Argentina-Chile treaty the border between the two nations.
Faults and glacier action have however made a gap at the site of
Huahum Pass where waters from the eastern Argentine slopes drains westward to the Pacific Mountains at the cordillera may reach at most some 2000 m in height. Andean valleys of Los Ríos Region are deep and broad and either used for raising cattle or for wood lodging, as well as tourism and protection of
biodiversity. These glacial valleys are placed above old
Miocene rivers and faults. The chief fault is the
Liquiñe-Ofqui Fault that crosses the whole region from north to south allowing numerous valleys to develop above it. The
Liquiñe-Ofqui Fault is tectonically active causing minor tremors and is also believed responsible by geologists for the alignment of the volcanoes of the southern section of the Southern Volcanic Zone. Along Liquiñe-Ofqui Fault there are several
hotsprings such as
Liquiñe,
Chihuío,
Termas Geométricas,
Termas Vergara and
Termas de Coñaripe.
Hydrography The region owes its name to the river network that converge in
Valdivia River at the city of
Valdivia. These rivers drain most of northern Los Ríos Region as well as parts of
Araucanía Region and
Neuquén Province in
Argentina. A second large river,
Bueno River is responsible for the draining of the southern parts of the region including
Ranco Lake, Chile's 4th largest lake. Bueno River and its tributary
Pilmaiquén River also drain large areas of
Osorno Province and form the southern boundary of the region. These two big river systems receive a continuous inflow of water due to being fed by lakes and lake chains in the Andes. Valdivia River is provided by the
Seven Lakes chain plus
Lácar Lake and
Bueno River from
Ranco,
Maihue and
Puyehue Lake. The large lakes in the interior are fed by rainwater and snow melt from the higher mountains.
Glaciers and semipermanent snow patches have relatively low share flow volume of the main rivers. ==Demographics==