February 03, 2019

Hassi Messaoud, Algeria’s biggest oilfield, lies in the Grand Erg Oriental of the Sahara desert.
The Sahara, world’s largest hot desert, stretches from the Red Sea in the east and the Mediterranean in the north, to the Atlantic Ocean in the west.
There was little interest to explore that immense desert. There were only two known oil seeps one in the north of the Cheliff, the other in Sidi Aissa, both in northern Algeria. In 1892 a British explorer drilled some wells producing just a few barrels of crude oil. Tiny field were discovered before 1950, north of the Atlas Mountain. Due to the sands, gravels and mountainous sand dunes, gravimetry results were poor.
In May 1956, SN REPAL (Société Nationale de Recherche et d’Exploitation de Pétrole en Algérie) found oil, flowing at 1,125 barrels per day at Hassi Messaoud located in the Ouargla province, at about 625 km south of Algiers. A few months later the company drilled Omj-1 at 8 km from the previous location. Omj-1 flowing at 2,500 barrels per day is considered as the Hassi-Messaoud field discovery. The Name Hassi Messaoud means the well of Messaoud in Arabic, named after Messaoud Rouabeh, a well-digger in the region. The oil field is a Cambrian sandstone reservoir 270 m thick in a dome 3300 m deep and 1300 km2 in area of the Oued Mya structural basin.
The gaz field of Hassi R’Mel was discovered shortly after. A total of 178 wells had been drilled to the end of 1967, 30 of which were producing at a rate greater than 6,000 barrels per day.
In 1979 Hassi Messaoud’s oil refinery was expanded, increasing its production capacity to about 9,500,000 barrels annually. In the early 1980s the field produced about half of the total Algerian oil output. Pipelines carry its oil to refineries in Algiers, Arzew, Bejaïa, and Skikda.
Operated by Sonatrach, the field produces today about 375,000 barrels of oil per day, 40 per cent of Algeria’s production. (Sources: AAPG, Aspo France – Drilling the discovery well in Hassi-Messaoud in 1956, image: CFPA)