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Search Results for "tibesti":

Dust in the Sahara Desert Near the Tibesti Mountains in Chad

November 19th, 2009 Category: Dust Storms

Sahara Desert - November 16th, 2009

Sahara Desert - November 16th, 2009

The Sahara is the world’s largest hot desert. At over 9,000,000 square kilometres (3,500,000 sq mi), it covers most of Northern Africa, including huge parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and Tunisia. The area visible here includes southern Libya (upper left), northern Chad (lower left), southern Egypt (top right) and northern Sudan (bottom right).

The desert landforms of the Sahara are shaped by wind or by occasional rains, and include sand dunes and dune fields or sand seas, stone plateaus, gravel plains, dry valleys and salt flats. Several deeply dissected mountains and mountain ranges rise from the desert, many of which are volcanic, including the Tibesti Mountains, identifiable here as a brown area along the left edge.

The Tibesti Mountains are a group of dormant volcanoes forming a mountain range in the central Sahara desert in the Bourkou-Ennedi-Tibesti Region of northern Chad. The northern slopes extend a short distance into southern Libya. Here, some whitish colored dust can be seen blowing to the southwest, below the mountain range.

The Tibesti Mountains Rising Above the Sahara Desert

21.6N 17.5E

May 9th, 2009 Category: Volcanoes

Chad and Libya - April 13th, 2009

Chad and Libya - April 13th, 2009

The Tibesti Mountains, the brown area on the left, are a group of dormant volcanoes forming a mountain range in the central Sahara desert in the Bourkou-Ennedi-Tibesti Region of northern Chad. The northern slopes extend a short distance into southern Libya, visible at the top.

The mountains are the largest and highest range in the Sahara, whose golden sands can be seen here curving around the base of the range.

The highest peak is Emi Koussi, 3,415 m. Other summits include Kegueur Terbi (3,376 m), Tarso Taro (3,325 m), the active volcano Pic Tousside (3,265 m) and Soborom (3,100 m).

While the high peaks themselves are all constituted of volcanic material, the mountains stand on broad uplifted area possibly caused by a mantle plume.

The range has a substantially wetter climate than the arid surrounding desert; annual rainfall is estimated at five inches (12 cm) in some of the highest areas of the mountains.

Draa Dunes in Southwestern Libya

25.9N 13.9E

August 4th, 2009 Category: Snapshots

Libya - May 30th, 2009

Libya - May 30th, 2009

Seas of fire-colored red, orange and yellow sand dunes occupy the arid terrain of southwestern Libya. Most of the dunes visible here are draa dunes (from the Arabic for “arm”), very large masses of sand separated by flat basins containing little sand.

The sandy area in the bottom right quadrant is part of the Murzuq Desert, a primarily erg desert that is considered part of the Sahara desert complex, although it is separated from the southern Sahara by the Tibesti Mountains and the Tassili n’Ajjer.

Sand Dune Seas and Volcanic Fields, Libya

April 19th, 2009 Category: Snapshots

Libya - April 9th, 2009

Libya - April 9th, 2009

This view of central and southern Libya shows an interesting contrast in landscape, between seas of high sand dunes called “ergs” and volcanic fields and mountain ranges.

Two ergs are visible here in the left portion of the image: the Erg Ubari (also called Awbari) and the Erg Murzuq (also called Murzuk). The Erg Ubari is more reddish in color and is located just above the center. It is separated from the Erg Murzuq by a swath of dark brown Nubian sandstone. Below this outcrop, the Erg Murzuq is partially covered by clouds.

On the right side of the image, at the top, the Haruj volcanic field is visible as a dark brown area, which in fact spreads across 45,000 km2 (17,000 sq mi) of central Libya. It contains about 150 volcanoes, including numerous basaltic scoria cones and about 30 small shield volcanoes, along with craters and lava flows.

South of the Haruj is another dark brown area: the Tibesti Mountains, a group of dormant volcanoes forming a mountain range in the central Sahara desert. The northern slopes extend a short distance into southern Libya, though the majority of the range is in northern Chad. These mountains are the largest and highest range in the Sahara.

Emi Koussi Volcano, Chad

January 29th, 2009 Category: Volcanoes

Emi Koussi volcano, Chad - January 27th, 2009

Emi Koussi volcano, Chad - January 27th, 2009

Emi Koussi is an extinct high shield volcano that lies at the south end of the Tibesti Mountains in the central Sahara of northern Chad.

It is the highest mountain in Chad, and also the highest in the Sahara. The volcano is one of several in the Tibesti massif, and reaches 3445 m (11302 ft) in altitude, rising 2.3 km (1.43 mi) above the surrounding sandstone plains. The volcano is 60 by 80 km (37 to 50mi) wide.

Upon more detailed examination, the rim of the volcano appears to consist of two rings. This is because two nested calderas cap the volcano, the outer one being about 12 by 15 km in size. Within it on the southeast side is a smaller caldera, about 2-3 km wide and 350 m deep.

Numerous lava domes, cinder cones, maars, and lava flows are found both within the calderas and along the outer flanks of the shield.

source Wikipedia