Karthala Volcano on Grand Comoro
Thursday, 20. November 2008, 20:04:04
From here it seems only a small hop from Madagascar to the Comoros Islands. Well I suppose that most of you know where Madagascar is. I wrote about it yesterday. The Comoros are probably well less known. They also lie in the Indian Ocean - somewhere between North Madagascar and the African coast (See map below).
The Comoros consist of volcanic effusive rocks, mainly basalt, and to a lesser extent trachyte and phonolite. Two thirds of the largest (and newest) of the islands, the Grande Comore Island, is formed by the Karthala volcano, a basaltic shield volcano with an active hydrothermal system. Mount Karthala is the highest point of the Comoros at 2,361 m above sea level. La Grande Comore is by the way also known as Ngazidja Island. Here are some of the eruption dates of Karthala over the last 1000 years or so: 2007, 2006, 2005, 1991, 1977, 1972, 1965, 1956, 1952, 1948, 1928, 1918, 1910, 1904, 1883-84, 1880, 1876, 1872, 1865, 1862?, 1860, 1859, 1858, 1857, 1855, 1850?, 1848, 1833, 1830, 1828, 1821, 1814, 1808, 1050. I think it is prudent to say that the volcano is extremely active, having erupted more than 20 times since the 19th century. Karthala contains a 3 x 4 km summit caldera generated by repeated collapse.
The volcanic chain of the Comoros apparently represents a “hot spot trace ”. The Comores islands and the tertiary volcanic province of Northern Madagascar form a sub-linear trend of alkalic shield volvanoes across the northern Mozambique Channel. Potassium-argon dating of shield building lavas confirms an eastward increase in age of volcanism along the chain, consistent with a hotspot origin for the lineament. The rate of migration of the Somali Plate over the mantle source is approximately 45 mm/yr.
Experts at a three-day conference on the slopes of the Karthala now say that the Comoros could tame the feared Karthala, which is indeed one of the world's largest active volcanoes, and use its geothermal and tourism potential to boost the archipelago's economy as a sort of goldmine for the Indian Ocean nation. One aim of the conference is to look at the possibility of exploiting this source of clean, renewable energy and transform it into a driving force for development. The volcano's ecotourism potential should also be examined during the conference.
The Comoros came to global attention in March 2008 when rebel leader Mohamed Bacar fled to France's Indian Ocean island of Reunion as African Union troops waded in to restore federal democratic institutions.
* http://www.terradaily.com/reports/Comoros_sees_future_in_volcano_economy_999.html
• http://www.volcano.si.edu/world/volcano.cfm?vnum=0303-01=
• http://adsabs.harvard.edu/abs/1985PhDT.........5E
The Comoros consist of volcanic effusive rocks, mainly basalt, and to a lesser extent trachyte and phonolite. Two thirds of the largest (and newest) of the islands, the Grande Comore Island, is formed by the Karthala volcano, a basaltic shield volcano with an active hydrothermal system. Mount Karthala is the highest point of the Comoros at 2,361 m above sea level. La Grande Comore is by the way also known as Ngazidja Island. Here are some of the eruption dates of Karthala over the last 1000 years or so: 2007, 2006, 2005, 1991, 1977, 1972, 1965, 1956, 1952, 1948, 1928, 1918, 1910, 1904, 1883-84, 1880, 1876, 1872, 1865, 1862?, 1860, 1859, 1858, 1857, 1855, 1850?, 1848, 1833, 1830, 1828, 1821, 1814, 1808, 1050. I think it is prudent to say that the volcano is extremely active, having erupted more than 20 times since the 19th century. Karthala contains a 3 x 4 km summit caldera generated by repeated collapse.The volcanic chain of the Comoros apparently represents a “hot spot trace ”. The Comores islands and the tertiary volcanic province of Northern Madagascar form a sub-linear trend of alkalic shield volvanoes across the northern Mozambique Channel. Potassium-argon dating of shield building lavas confirms an eastward increase in age of volcanism along the chain, consistent with a hotspot origin for the lineament. The rate of migration of the Somali Plate over the mantle source is approximately 45 mm/yr.
Experts at a three-day conference on the slopes of the Karthala now say that the Comoros could tame the feared Karthala, which is indeed one of the world's largest active volcanoes, and use its geothermal and tourism potential to boost the archipelago's economy as a sort of goldmine for the Indian Ocean nation. One aim of the conference is to look at the possibility of exploiting this source of clean, renewable energy and transform it into a driving force for development. The volcano's ecotourism potential should also be examined during the conference.
The Comoros came to global attention in March 2008 when rebel leader Mohamed Bacar fled to France's Indian Ocean island of Reunion as African Union troops waded in to restore federal democratic institutions.
* http://www.terradaily.com/reports/Comoros_sees_future_in_volcano_economy_999.html
• http://www.volcano.si.edu/world/volcano.cfm?vnum=0303-01=
• http://adsabs.harvard.edu/abs/1985PhDT.........5E
WIDGETIZE