Oil spill in the Ecuadorean Amazon.

Around 10 000 barrels (slightly under 1.2 million liters) of crude oil leaked into the Coca River in eastern Ecuador following the rupture of the 30 year old Trans-Ecuadorian Oil Pipeline, operated by the state owned Petroecuador oil company. The river is a tributary of the Napa River, which in turn supplies water to the Amazon. It is also the main supply of fresh water to the town of Francisco de Orellana, which has a population of 60 000 and lies on the junction of the Coca and Napa rivers. A pumping station used by the town has been turned off, and people are being advised not to drink well water, while supplies of bottled water are brought in by truck. The spill is reported to have been caused by a mudslide on El Reventador Volcano.

Map showing the relative positions of the Trans Ecuadorian Pipeline and the Reventador volcano, from a report into damage caused to the pipeline by the volcano in a 1987 incident - suggesting this is not a new problem. Schuster et al. (1991).

The Trans Ecuador Pipeline carries crude from oil fields in the Ecuadorian Amazon to the port of Esmeraldas on the Pacific coast. The project was originally a joint project between US oil company Texaco and the Ecuadorian Government, but was taken over entirely by the Ecuadorians in 1990 following a series of environmental problems in the previously pristine rainforest. This does not seem to have improved the situation, with leaks remaining frequent in the area. The Ecuadorian government has been involved in a protracted legal dispute with Chevron, Texaco's parent company, for some years, with Ecuador claiming restitution for environmental damage on behalf of the people of the Amazon Basin, and Chevron refusing to settle on the grounds that much of the environmental damage has occurred since the government took over the operation. 

In May 2013 a court in Argentina froze Chevron's assets in that country over companies refusal to comply with legal rulings in Ecuador, potentially halting the company's planned exploitation of the Vaca Muerta shale formation in that country.

See also Plains Midstream Canada charged over April 2011 Alberta oil spill, Oil spill in Bayelsa State, Nigeria, Homes evacuated after Arkansas oil leak, Eruption on Volcán El Reventador and Chevron & Ecuadorian government seek to use arbitration to settle Amazon damages case.

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Eruption on Volcán El Reventador.

Volcán El Reventador is a 3562 m volcano rising out of the jungle of the western Amazon Basin, and considered to be one of the most active volcanoes of the Ecuadorean Cordillera Real. The volcano comprises a on older, forested, 4 km wide caldera, open to the east, with a younger, unforested, active stratovolcano (cone shaped volcano) within, rising 1300 m above the caldera floor. The recorded history of Volcán El Reventador goes back to April 1541, with at least 25 major eruptions in this time, though it is quite likely that some will have been missed, due to the remote location of the volcano. The largest recorded eruption on Volcán El Reventador occurred in 2008, when an ash-column rose 6 km into the air and was accompanied by explosions, pyroclastic flows, lava flows and lahars.

A steam plume rising above Volcán El Reventador in February 2012. Endless River Adventures.

Volcán El Reventador has produced columns of ash and steam for much of 2012, but has otherwise been inactive. On 3-4 November an ash plume rose 3 km above the summit, and on 9 November, following a visit to the site by volcanologists, the Instituto Geofísico-Escuela Politécnica Nacional reported a new phase of activity had started on the mountain, with lava flows on the north and south flanks of the volcano, up to 2 km in length, and a lava dome (mound-shaped protrusion resulting from the slow extrusion of viscous lava) rising above the crater walls. On 13 November the Washington Volcanic Ash Advisory Center reported an ash column from Volcán El Reventador rising 5.2 km and drifting to the southeast.

The volcanoes of the Cordillera Real, and of South America in general, are fueled by the subduction of the Nazca Plate beneath the South American Plate. The Nazca Plate underlies a large chunk of the eastern Pacific Ocean, and is being subducted along Peru-Chile Trench to the west of South America. As it sinks into the Earth, the Nazca Plate passes under South America, where it is heated by friction with the overlying South American Plate and by the heat of the planet's interior. This causes the Nazca Plate to partially melt, and some of this melted material then rises through the South American Plate as magma, fueling the volcanoes of the Andes. The motion of one plate beneath another is not a smooth process, and the Nazca and South American Plates frequently stick together, then break apart as the pressure builds up, triggering frequent Earthquakes along the western coast of South America, and sometimes further inland.

The subduction of the Nazca Plate beneath the South American Plate, and how it causes Earthquakes and volcanoes. SIO SEARCH.

See also Massive Earthquake deep beneath Columbia, Seismic activity beneath Mount Sotará, Columbia, Seismic activity on Mount Cumbal, Colombia, Earthquake off the coast of Chiloé Island, Chile and Volcanoes on Sciency Thoughts YouTube.

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