#afar depression

[dailyhistoryposts]

On This Day In History

November 24th, 1974: Donald Johanson and Tom Gray discover the 40% complete Australopithecus afarensis skeleton, nicknamed "Lucy" in the Awash Valley of Ethiopia's Afar Depression.

[earthstory]

Lava Lake at Erta Ale Lava lakes are a relatively rare phenomenon; currently only seven are known to exist in the world (an eighth, at Kilauea volcano, drained away in 2018). The lava lake in this photo is located in the summit caldera of Erta Ale volcano in the Erta Ale Range of Ethiopia.

Erta Ale is a basaltic shield volcano located within the Afar Depression – a tectonically active region where the Earth’s crust is rifting (http://on.fb.me/1r9pNGC). At 613 meters tall it’s not the highest point in the Erta Ale Range, but it is the most active volcano in all of Ethiopia. It’s been erupting continuously since 1967. Erta Ale’s lava lake is known for being particularly long-lasting; it has been there since at least 1967 and possibly as far back as 1906 (scientists aren't sure since it’s a very remote location and, even today, is not routinely monitored). At times a second lava lake has also been observed. In order for a lava lake to exist, the molten rock must be consistently resupplied, as the surface is always losing heat and crystallizing. There is a large amount of magma right below Erta Ale’s lava lake that keeps it heated. Even so, the lake goes through cycles where it cools and crusts over only to suddenly become molten again. If the crust is sufficiently thick to trap heat long enough for pressure to build, plumes of molten rock 2 to 4 meters high can burst through the black crust. Every so often, the lava lake at Erta Ale overflows the caldera. When this happens, lava flows down the mountain where it may endanger inhabitants. Despite the inhospitable terrain and remoteness of the volcano, the lava lake is becoming a tourist attraction. In 2002, the only way to access the volcano was by helicopter; now roads allow people to get within 7 kilometers from the volcano. - RE Photo Credit: Joel Santos http://bit.ly/1eRdcmC References: http://bit.ly/1dP6rBI http://bit.ly/1JtcY0i

[sitting-on-me-bum]

Dallol, which is better known as Dallol Volcano and also as Dallol Hydrothermal Fields, is a volcanic explosion crater which is located in the Danakil Depression, in the Federal Democratic Republic of Ethiopia.

By mauro gambini

[wigmund]

From NASA Earth Observatory Image of the Day; January 28, 2017:

Fissure Eruptions on Erta Ale

In Africa’s Danakil (or Afar) Depression three tectonic plates are tearing themselves apart in spectacular fashion. As the plates separate, several active volcanoes have emerged along the seams. One of the most active is Erta Ale, a shield volcano near the Ethiopian and Eritrean border. It is known as the “smoking mountain” and the “gateway to hell” in the Afar language.

Erta Ale has a long-lived lava lake that has gurgled and spattered in its caldera for decades, but the most recent bout of activity involves the southeast flank of the gently sloping mountain. According to reports posted by Volcano Discovery, new fissures opened up on January 21, 2017, about 7 kilometers (4 miles) from the summit caldera, spilling large amounts of lava. Meanwhile, at least one of the lava lakes has experienced large changes in the level of its lava that have led to overflows and intense spattering.

This image was captured by the Operational Land Imager (OLI) sensor on Landsat 8 on January 26, 2017. It is a composite of natural color (OLI bands 4-3-2) and shortwave infrared (OLI band 7). Shortwave infrared light (SWIR) is invisible to the naked eye, but strong SWIR signals indicate increased temperatures. Infrared hot spots representing two distinct lava flows are visible. Plumes of volcanic gases and steam drift from the lava lakes.

References

Atlas Obscura (2017, January 25) Erta Ale. Accessed January 27, 2017.

Global Volcanism Program Erta Ale. Accessed January 27, 2017.

The Watchers (2017, January 25) New flank eruption at Erta Ale volcano, Ethiopia. Accessed January 27, 2017.

Volcano Discovery (2017, January 25) Erta Ale volcano (Ethiopia): new flank eruption reported. Accessed January 27, 2017.

NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey. Caption by Adam Voiland. Instrument(s): Landsat 8 - OLI

[pangeen]

Portrait of a smiling afar tribe girl, Afar region, Semera, Ethiopia par Eric Lafforgue

[livingnomads-blog1]

10 most dangerous places in the world that you probably won't want to visit

10 most dangerous places in the world that you probably won’t want to visit

Our planet is an exciting, beautiful, fascinating place which never cease to surprise us in its diversity and vitality. It’s home to magnificent mountains, wondrous volcanoes, majestic rivers, endless deserts, and so much more. Yet no matter how beautiful our planet is, we should never forget how dangerous nature can be.

Today, we here at Bright Side have prepared a list of the most thrilling and…

View On WordPress

[earthstory]

"Lava Vertebrae" Afar Depression

Located close to the Awash River in the Afar Depression, Ethiopia, these "back bones" are eroded ancient lava flows.

The Afar depression is caused by a geological “triple junction”- a point where the boundaries of three tectonic plates meet, and in this case, these are; the Red Sea Rift, the Aden Ridge and the East African Rift.

The Afar depression is one of only two places on the Earth that a “mid-ocean ridge” can be studied on land (the other is Iceland), and the spreading center is moving at about 2cm a year. As a result of the triple junction, the geology here is exciting! There are continuous earthquakes, fissures opening up that are sometimes 100’s of meters long, volcanic eruptions are common place and there is emplacement of dykes and sills that geologists can see and measure.

The region is also home to Erta Ale, the famous basaltic shield volcano, that is almost continuously erupting.

-LL

Links: http://ngm.nationalgeographic.com/2012/01/afar-depression/steinmetz-photography#/04-ancient-lava-flows-670.jpg http://www.scientificamerican.com/article.cfm?id=birth-of-an-ocean http://geology.com/articles/east-africa-rift.shtml http://earthobservatory.nasa.gov/IOTD/view.php?id=77566 http://education.nationalgeographic.com.au/education/encyclopedia/rift-valley/?ar_a=1

Image: George Steinmetz (http://www.georgesteinmetz.com/)

[earthstory]

Hot Springs, Afar Depression. Looking like a hostile alien landscape, these hot springs are located in the Afar Depression in East Africa. The depression is caused by a geological “triple junction”, and here the Red Sea Rift, the Aden Ridge and the East African Rift all meet. The Afar depression is one of only two places on the Earth that a “mid-ocean ridge” can be studied on land (the other is Iceland), and the spreading centre is moving at about 2cm a year. As a result of the triple junction, geology here is exciting! There are continuous earthquakes, fissures opening up that are sometimes 100’s of metres long, volcanic eruptions are common place and there is emplacement of dykes and sills that geologists can see and measure.  But what about the picture?  The springs in the picture formed from condensation of gasses rising from the magma chambers below (related to the rift). In the hot East African sun, the water evaporates, and minerals and salts dissolved within precipitate out and form thick crusts. Sulphur, bacteria and algae form the vivid colours, and add to the “out-of-this-world” feel of the landscape. -LL Links; http://photography.nationalgeographic.com.au/photography/photo-of-the-day/hot-springs-afar-steinmetz/ http://www.scientificamerican.com/article.cfm?id=birth-of-an-ocean http://geology.com/articles/east-africa-rift.shtml http://earthobservatory.nasa.gov/IOTD/view.php?id=77566 http://education.nationalgeographic.com.au/education/encyclopedia/rift-valley/?ar_a=1 Image; George Steinmetz