Tat Ali is a low Holocene shield volcano located in the northern part of the Afar Region

Afar Region

Afar is one of the nine ethnic divisions of Ethiopia, and is the homeland of the Afar people. Formerly known as Region 2, its current capital is Asayita; a new capital named Semera on the paved Awash - Asseb highway is under construction....

 of Ethiopia

Ethiopia

Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...

. This elevation is characterized as having an elongated summit depression that has produced a variety of rock types, ranging from basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

s to pantellerite

Pantellerite

Pantellerite is a peralkaline rhyolite. It has a higher iron and lower aluminium composition than comendite. It is named after Pantelleria, a volcanic island in the Strait of Sicily and the type location for this rock. On Pantelleria the rock is usually found as a vitrophyre containing phenocrysts...

s. NNW

NNW

NNW may refer to:*National Nurses Week, the week of May 6 through May 12 proclaimed by Richard Nixon in 1974 as a period for Americans to recognize nurses' service and contributions...

-SSE-trending fissures cutting the volcano have fed basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic lava flows; those NE of Lake Afrera

Lake Afrera

Lake Afrera is a hypersaline lake in northern Ethiopia. Located in Administrative Zone 2 of the Afar Region, it is one of the lakes of the Danakil Depression. According to its entry in Lakenet, it has a surface area of , although another source states the area is 12,500 hectares...

 are of prehistoric date. Late-stage volcanism produced youthful basaltic lava flows on the floor of the summit depression, which is also the site of prominent fumarolic activity.

Tat Ali, Erta Ale

Erta Ale

Erta Ale is a continuously active basaltic shield volcano in the Afar Region of northeastern Ethiopia, the most active volcano in Ethiopia. It is in the Afar Depression, a badlands desert area spanning the border with Eritrea, and the volcano itself is surrounded completely by an area below sea...

, Alu and other Ethiopian highlands

Ethiopian Highlands

The Ethiopian Highlands are a rugged mass of mountains in Ethiopia, Eritrea , and northern Somalia in the Horn of Africa...

are together known as the Danakil Alps.