Karoo Supergroup of the country, and in the Lebombo mountains along the Mozambique border. Once the layer of hard lava was eroded away, the softer Karoo sediments over the rest of the basin eroded even faster. However, the dolerite sills resisted erosion, protecting the softer Beaufort and Ecca shales beneath them. This created numerous and widespread flat topped hills, known as Karoo Koppies ("koppie" being the Afrikaans term for hill), which are iconic of the Karoo, and, by extension, the South African landscape. The dykes, or vertical fissures which brought the lava to the surface stand out today as linear ridges extending
The Oregon Desert The Oregon Desert The Oregon Desert is a non-fiction book about the high desert region of eastern Oregon. It highlights both the people and natural history of Oregon's high desert country using serious science, first-hand narrative history, and humorous anecdotal stories. It was written by E. R. Jackman and R. A. Long. The book was first published in 1964 and has never been out of print since its initial release. Edwin Russell (E.R.) Jackman was an American agricultural expert from Oregon. He worked for Oregon State University as a rural extension agent and a farm crop specialist from 1929 until