Karoo Supergroup divided into (from oldest to youngest): Karoo Supergroup The Karoo Supergroup is the most widespread stratigraphic unit in Africa south of the Kalahari Desert. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the Late Carboniferous and Early Jurassic, a period of about 120 million years. In southern Africa, rocks of the Karoo Supergroup cover almost two thirds of the present land surface, including all of Lesotho, almost the whole of Free State, and large parts of the Eastern Cape, Northern Cape, Mpumalanga and KwaZulu-Natal Provinces of South Africa. Karoo supergroup outcrops are also found
Semi-arid climate Diego, California (at its main airport), which has cool summers for the latitude due to prevailing winds off the ocean (so the average annual temperature is below 18°C) but mild winters (average temperature in January, 14°C, and closer to the 18.0°C isotherm that separates tropical and subtropical climates than to the 0°C or −3°C isotherm for the coldest month that separates temperate and continental climates). </ref> Semi-arid climate A semi-arid climate or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid