Ecuadorian Geography

Ecuador (official name: República del Ecuador) is a country located in the northwestern part of South America. Ecuador borders Colombia to the north, Peru to the south and east, and the Pacific Ocean to the west. The country has an area of 283,561 km². In addition to the continental territory, Ecuador is made up of the Colón archipelago, apart from others close to the mainland, such as Puná, Santay, and the Isla de la Plata.

Ecuador is located on the terrestrial equatorial line, which is why its territory is located in both hemispheres. It comprises two distant spaces: the continental territory to the northwest of South America with some islands adjacent to the coast, and the archipelago of Galapagos (Insular region), which is ~1000 km from the Ecuadorian coast or coastline in the Pacific Ocean. The country is crossed from north to south by the Andes mountain range, in the western foothills of the mountain range are the lowlands that border the Pacific Ocean, to the east of the mountain range are the lowlands that are part of the Amazon plain. The Ecuadorian Andes are divided into two mountain ranges, the Western and the Eastern or Real, both exceeding 5000 meters above sea level; These are linked by transversal knots that delimit inter-Andean valleys. In the Upper Amazon there are branches of the Andes such as the Napo-Galeras, Cutucú and Cóndor mountain ranges.

Territorial Boundaries

It borders Colombia to the north, Peru to the south and east, the Pacific Ocean to the west, and Costa Rica through the territorial sea of the Galapagos Islands.

Physical geography

Location

Ecuador is located between two hemispheres apart from being crossed by the equatorial line or parallel, 0° latitudinal; much of the territory is in southern latitude. The national territory is located longitudinally to the west of the Greenwich meridian, therefore it has a western longitude. The continental territory covers the northeast of South America and the island territory (Colón archipelago) is located to the west of the continental territory, approximately 1000 km.

Extreme Points

Continental Territory

• To the north, mouth of the Mataje river (01o 21' 10.50)
• To the south, the confluence of the San Francisco River and the Chinchipe River (5° 00' 56)
• To the east, the confluence of the river Napo and the river Aguarico (75° 11' 49)
• To the west, island of La Plata (81° 04' W)

Insular Territory

• Latitude: from Charles Darwin Island (1° 39' N), to the Spanish island (1° 26' S).
• Length: from San Cristobal Island (89° 15' W), to Charles Darwin Island (92° 01'W)

Geology and Geomorphology

The Cordillera de los Andes is made up of a double mountain range that presents great ramifications towards the outer flanks (western and eastern) dividing the continental territory into three regions: Coast, Sierra and Oriente. In addition to the continental area, it is integrated into the country; the insular region made up of islands emerging from the Pacific Ocean due to submarine volcanic eruptions.

It is characterized by a variety of relief, whether they are the product of tectonic processes (endogenous) and morphoclimatic conditions, volcanism (exogenous), among others.

The cordilleras become mountainous barriers made up of a framework of ancient rocks, volcanic sediments (Eastern Cordillera) and metamorphic (Eastern Cordillera), in turn within the cordilleras depressions and tectonic trenches extend that have been filled by sediments detrital and volcanic. The eastern slope of the Andes specifically at the foot of the mountain extends and the Napo Uplift, to the north, and the Cutucú and Cóndor mountain ranges, to the south, all of these are sub-Andean zones. In the coastal region there is an arching mountain range that goes from Guayaquil and continues to the northwest and north.

Due to marine transgressions and regressions on the Coast and Amazonia, large sedimentary rocky strata have been deposited which, due to tectonic activity and erosion, formed tabular reliefs, synclines, anticlines, and tectonic pillars. Recent marine deposits are found on the beaches, salt flats, flatlands, mangroves, and coastal fringes. The plains located in the Amazon (northern part of the region) and coastal zone (east central part) are of agricultural importance.

Geographic Regions

Coast or Littoral

The Costa region of the country is made up of hilly reliefs and plains.

It extends from the coastal profile to the western slope of the Andes Mountains at approximately 1,200 m above sea level. It has an approximate extension of 670 km long and 150 km wide; its greatest width covers the Guayaquil-Portoviejo latitudinal strip and in the south of Guayaquil the area narrows.

To the East, a piedmont zone is characterized by homogeneous relief, later the low zone of 30 to 80 km wide, is located in the Center-East and to the south of the region a plain of flat relief extends to surfaces slightly undulating, to the south of Babahoyo a low alluvial plain stretches out, with altitudes below 20m.

The region is made up of coastal mountain ranges that do not exceed 800 m in height, these are: Chongón- Colonche, Mache Chindul, Jama, Balzar, Cojimíes and Convento.

Andes, Sierra or Interandina

Formed by two mountain ranges: the Western and the Eastern arranged in a meridian direction, with steep outer slopes. From the border with Colombia (Nudo de los Pastos) to Alausí (Paute - Girón depression) there are volcanoes of explosive dynamism. In the southern section of the mountain range, the two sections of the mountain range do not differ because the relief does not exceed 4000 m in height, that is, they present a relief of high plains with undulating surfaces.

This geographical barrier is made up of three successive sections, where their directions change slightly; The first section is described in the north of the country near the border with Colombia and the equator line. The mountain range follows a dominant SSO-NNE and SW-NE orientation at its northern end and extends in this direction towards Colombia; the next section, the center between parallel 2°30'S and the equator line, the mountain range presents an almost perfectly meridian direction, in this section the Andes have their smallest lateral development; In the southern part of the 2°30'S parallel, the axes of the relief present a net direction SSO-NNE, parallel to the layout of the coastline, and continue in the same way in the extreme north of the Peruvian Andes.

Serranias in the Ecuadorian Southern Andes.

Northern Andes

Going from the border with Colombia to Palmira-Alausí, the mountain range presents aspects described by Humboldt as the Avenue of the Volcanoes, it presents very steep external flanks that dominate the coastal and Amazonian regions with slopes of 3,000 meters above sea level sea approximately and with elevations that vary in altitude ranging from 4,000 m to 4,500 m in both meridian cordilleras in the center and curved towards the east in the far north; The reliefs in this area are vigorous, marked by the last glaciation in the Quaternary on the tops and attenuated by successive deposits of volcanic products. The Western and Eastern cordilleras are separated by an intramontane depression, the inter-Andean valley or alley, with With a width of less than 40 km, the graben extends to Loja and El Oro. Seismic activity is more frequent in the Cordillera Real than in the Western one, there is Quaternary tectonic activity in the inter-Andean valley and in the Cordillera Real.

Central Andes

It refers to the area that goes from Riobamba to the south, it does not present volcanic buildings on the two slopes as well as in the central depression (Palmira-Alausí), it presents characteristics similar to the altiplano, this relief arises from foundations made up of large volcanic spills. In this area, the Andes extend up to 40 km west of Cuenca, its altitude drops progressively to the south, to the west of Zaruma they culminate at 3800 m. The inter-Andean depressions lose sharpness to the north, with the exception of the Cuenca and Cañar sedimentary basins, wider valleys, which are staggered between Santa Isabel (1,600 m) and Saraguro (2,500 m).

Southern Andes

Going from the Zaruma-Saraguro parallel to the border with Peru, the Cordillera Real extends, albeit in a fragmented way, to Amaluza, where it culminates at 3,900 meters. It is characterized by low relief, generally to the SSO. The highest points do not exceed 2,500 meters, they do not present traces of glaciation. It presents an association of large upper elongated ridges, associated with widened transversal valleys and with orthogonal layouts, those of the Catamayo or Puyango rivers, which drain into small depressed and isolated basins.

Oriental or Amazonian

The general relief of the Ecuadorian Amazon region consists of plains and penillanuras.

It extends from the eastern slope of the Andes Mountains. It is divided into the upper Amazon, between heights of 500 and 1,500 m and below 300 m to the east, the border with Peru, extends the Amazon plain, made up of small hills approximately 50 m high.

Insular or Galapagos

Santa Cruz Island

The Galapagos Islands (also the Galapagos Islands and officially the Colón Archipelago) constitute an archipelago in the Pacific Ocean. Located at the junction of the Carnegie Range with the Cocos Range, which constitute the Galapagos platform. It is made up of 13 large volcanic islands, 6 smaller islands and 107 rocks and islets, distributed around the line of the Earth's equator. The islands are made up of volcanoes that emerge from the sea with gentle slopes, calderas that culminate at approximately 1,600 m. The entire archipelago has a total extension of 8,010 km².

It is estimated that the formation of the first island took place more than 5 million years ago, as a result of tectonic activity. The most recent islands, called Isabela and Fernandina, are still in the process of forming, with the most recent volcanic eruption having been recorded in 2009.

Volcanism

Chimborazo

Tungurahua

Sangay

Reseller

Cotopaxi

Antisana

Cayambe

Pichincha

Sumaco

Chiles- Cerro Negro

Imbabura

Some volcanoes from the continental area of the country.

Alcedo

Wolf

Sierra Negra

Fernandina

Cerro Azul

Darwin

March

Santiago

Some volcanoes of the Archipelago of Columbus or Galapagos.

The northern part of the country is culminated in an avenue of large volcanic edifices, whose pyroclastic materials extend and cover the north-central part of the country; Regarding the volcanism of the Galapagos Islands, it is of the Hawaiian type and exhibits huge calderas with shield-shaped cones.

The volcanic front of the western cordillera presents large volcanic edifices that have variable ages, but that do not exceed 1.3 million years, Guagua Pichincha is the only volcanic center within the western cordillera that has had eruptions in historical times that is to say, since 1532, but it is worth mentioning that studies indicate that the Quilotoa, Ninahuilca, Pululahua and Cuicocha have registered eruptions in the course of the last 3000 years, for which they are considered "potentially active".

Many of the volcanoes of the western cordillera are morphogeologically complex because they are formed by ancient or andesitic edifices and a recent or dactitic one, this is explained since their formation began during the Pleistocene epoch, characterized by the formations of large stratovolcanoes from 15 to 20 km in diameter that emitted andesitic magmas, examples of which are described in Cotacachi, Casitahua, Rucu Pichincha, Iliniza; At the end of the Pleistocene epoch and during the Holocene, the activity on the volcanic front was characterized by dacitic magmatic eruptions, which were explosive, in evidence the Cuicocha, Pululahua, Guagua Pichincha, Ninahuilca or Quilotoa volcanoes stand out.

These volcanoes are located in the volcanic axis of the inter-Andean valley of the Ecuadorian Andes, they are distributed from the border with Colombia to the north to the area of Riobamba in the south, they have a width of approximately 10 to 20 km with elevations that go from 3800 to 4700 meters; They are characterized by being highly eroded and extinct buildings with the exception of the Imbabura volcano which shows signs of eruptive activity in the Holocene, it is worth mentioning that the Mojanda-Fuya-Fuya volcanic complex, eruption deposits have been found during the late Pleistocene period. The northernmost volcanoes of the inter-Andean alley are the Iguán and Chaquilulo hills, in the southern section in which the alley takes a north-south direction the Mojanda-Fuya Fuya, Cusín, Imbabura and Cubilche volcanoes are located, more to the south, specifically To the southeast of the city of Quito, stratovolcanoes such as Ilaló, Pasochoa and Rumiñahui are located longitudinally. Within the valley in the north of Ambato is the Sagoatoa stratovolcano and its Unamuncho cone, on the other hand the buildings of Igualata, Mulmul, Calpi and Llimpi are distributed adjacent to the city of Riobamba, as well as slag buildings of Tulabug and Aulabug; the oldest eruptions from these volcanoes date from the Pleistocene epoch.

In the Cordillera Real there are volcanic edifices distributed randomly, forming a third row of volcanoes that belongs to the Ecuadorian Arc. The strip measures about 350 km with a width of 30 km and is subparallel to the Western Cordillera. The volcanic edifices are characterized by being large with diameters of 10 to 20 km and heights of up to 5900 meters, they are fairly uniform stratovolcanoes, with andesite-type magma. On the other hand, the Cayambe, Soche and Cotopaxi volcanoes have commonly recorded dacite and rhyolite eruptions. The Cordillera Real presents two large magmatic systems: the Chacana and Chalupas calderas, which during the late Pleistocene were characterized by rhyolitic eruptions.

The formation and destruction of the volcanic edifices in the Cordillera Real occurred during the late Pleistocene, the youngest cones formed in the Holocene are from Cotopaxi, Tungurahua, Cayambe, Sangay and perhaps Antisana. The volcanoes of the Eastern Cordillera, due to the presence of glaciers, as well as their height, are potentially dangerous in future eruptions.

Seabed

According to national jurisdiction, the seabed constitutes the soil and subsoil that are found on the continental platform according to Part VI of the United Nations Convention on the Law of the Sea of 1982. The continental margin is the prolongation which is submerged from the continent and extends to where the continental crust meets the oceanic crust.

Geologically, the margin is made up of the passive margins (shelf, slope and continental rise), these margins are linked to the formation of new oceanic crust at mid-oceanic ridges, on the other hand the active or convergent margins (shelf and slope), the slope ends at the deep trench or margins of the Pacific Ocean, these contribute to the subduction destruction of oceanic crust in the trench, where two plates converge

Deletion of transformative fault which moves the segments of the Galapagos Dorsal (red), is segmented as zig- zag.

Transform margins form the boundaries of two plates which move parallel to each other in opposite directions. Mid-ocean ridges are segmented and split along transform faults such as the Galápagos ridge fanned out along the Panama fracture zone.

Continental Shelf

It belongs to the subduction or active continental margins, which is characterized by a steep slope that ends in the trench (30-50 miles from the shore) and a narrow continental platform, this platform reaches depths of more than From 1,500 meters to a few miles from the coast, terrigenous sediments have been deposited on the platform as a result of alluvium.

The Galapagos submarine platform is made up of the Carneige mountain range and the Cocos mountain range. Carneige extends to the East to the oceanic trench, said mountain range has an extension of 1350 km long and 300 km wide, in addition to having a height of 3000 meters with respect to the surrounding oceanic floor, on the other hand Cocos is a submarine mountain range which extends northeast to the Central American trench, has a length of approximately 1000 km and a width of 200 km, both ranges originated in the Galápagos hotspot, that is, they are part of the same melting anomaly in the hot spot varying its thickness of the crust. Ecuador can extend beyond 200 meters through the Galápagos platform, for this, technical information must be submitted to the Continental Platform Limits Commission (CLPC), in accordance with the Technical and Scientific Guidelines of the Continental Shelf Limits Commission (UNDOC CLCS-11). The elevations of the Galapagos and the shelf originated from the incidence of the pu Galapagos hot weather, which gave rise to seamounts that are not part of the deep ocean.

Edaphology

Hydrography

Almost all of the rivers in Ecuador originate in the Sierra region and descend east to the Amazon River or west to the Pacific Ocean. Rising rivers from snowmelt on the edges of snow-capped peaks or from abundant rainfall that falls at higher elevations. In the Sierra region, streams and rivers are narrow and flow rapidly on steep slopes. The rivers can slow and widen as they cross the basins, becoming rapid once more as they flow from the heights of the Andes to the lower elevations of the other regions.

Satellite view of the Gulf of Guayaquil.

In the Coastal region, the External Coast has mostly intermittent rivers that are fed by the constant rains from December to May and become empty channels during the dry season. The few exceptions are the longer, perennial rivers that flow along the Costa del Externa Interna Costa and the Sierra on their way to the Pacific Ocean. The Internal Coast, on the other hand, is crossed by perennial rivers that can flood during the rainy season, sometimes forming swamps.

The Guayas estuary system, which flows south to the Gulf of Guayaquil, is the most important drainage system in the interior of the coast. The Guayas Basin, including the land drained by its tributaries, is 40,000 square kilometers in area. The Guayas, sixty kilometers long, rises north of Guayaquil at the confluence of the Babahoyo and Daule rivers. In short, constrained to Guayaquil by hills, the Guayas expands south of the city and flows through a network of small delta islands and canals. At its mouth, the river forms a wide estuary with two channels around Isla Puná, the deeper one being used for navigation.

The second major river system, Costa del Esmeraldas, rises from the Hoya de Guayllabamba in the Sierra as the Guayllabamba River and flows west to empty into the Pacific Ocean east of the city of Esmeraldas. The Esmeraldas River is 320 kilometers long and has a drainage basin of 20,000 square kilometers.

The main rivers in the Oriente include the Pastaza, Napo and Putumayo. The Pastaza is formed by the confluence of the Chambo and Patate rivers, both of which are born in the Sierra. The Pastaza includes the Agoyán waterfall, which at sixty-one meters is the highest waterfall in Ecuador. The Napo rises near Mount Cotopaxi and is the main river used for transportation in the eastern lowlands. The Napo ranges in width from 500 to 1800 meters. In its upper course, the Napo flows rapidly to the confluence with one of its main tributaries, the Coca River, where it slows and levels out. The Putumayo is part of the border with Colombia. All these rivers flow into the Amazon River.

The Galapagos Islands have no major rivers. Several of the larger islands do, however, have sources of fresh water.

Climate

Due to the presence of the Andes mountain range and depending on the influence of the sea, continental Ecuador is climatologically fragmented into various sectors.

In addition, due to its equatorial location, each climatic zone has only two defined seasons: wet and dry, erroneously called «winter» and «summer» respectively, as occurs in other regions of the globe where, due to their locations close to the equator, true winters and summers do not occur.

Both on the coast and in the East, the temperature oscillates between 20 °C and 33 °C, while in the mountains, it is usually between 3 °C and 26 °C. The wet season extends from December to May on the coast, from November to April in the mountains, and from January to September in the Amazon. Galapagos has a rather temperate climate and its temperature ranges between 22 and 32 °C, approximately.

These wet and dry seasons cause each region of the country to have different weather seasons. The temperatures are very variable.

Thus, from January to March it is mainly a dry season in the mountains, while on the coast and Amazon it is a wet season, with most cloudy days. On the contrary, from July to September in the mountains it is a wet season, while on the coast, dry.

Political geography

According to the National Institute of Statistics and Censuses (INEC), the country has 24 provinces, 221 cantons, 405 urban parishes and 778 rural parishes at the level of the Political-Administrative Division of the Republic from Ecuador.

Environment and ecology

Biomes of Ecuador

Tropical BiomassTropical humid forestDry forestFlooded savannahs and meadowsBiomas SecosMatorral xerophile Biomas MontanosMountain slopes and bushes Aquatic biomasManglar

Natural threats

The Ecuadorian geographic space has been the scene of several natural events, which in some cases have been catastrophic. Due to their magnitude, they have exceeded the response of society due to the absence of predispositions and adequate means to overcome them.

They are classified according to their origin:

Morphoclimatic phenomena

It is related to the morphology of the terrain and the climate, mainly with the amount of rainfall, temperature, slope of the terrain and bearing capacity of the soil. In Ecuador these phenomena have become frequent due to climate change and anthropogenic effects, an example of which is the severe flooding caused by the El Niño phenomenon (1982, 1983, 1992, 1993, 1997, 1998, 2007, 2008), which have affected a large part of the lower basin of the Guayas River or the landslide on the southern flank of Cerro Tahual that blocked the drainage of the Cuenca and Jadán rivers, in addition to countless small landslides.

Geological-endogenous phenomena

They are related to tectonic activity, they produce volcanic eruptions, tsunamis and earthquakes. As events we can mention the earthquakes in Pelileo (1949), Esmeraldas (1976), Pujili (1996), among others, as well as eruptions of the volcanoes Tungurahua, Guagua Pichincha, Reventador, recently from Sangay (2021).

See also

• Geographical regions of Ecuador
• Demography of Ecuador
• Ecuador
• Biodiversity of Ecuador