Benue Trough the Central African Shear Zone and for the volcanic island of St. Helena in the Atlantic ocean. Three periods of magmatic activity (volcanic action) have been identified, 147–106 Ma, 97–81 Ma and 68–49 Ma. The first is prominent in the north of the trough, and contemporary with magmatism in Brazil, probably occurring during a period of crustal extension before the Atlantic started to open. The second is found only in the south of the trough, and may belong to a period when the extension of the Atlantic had slowed down, ending with a period of compression. The third and last
How Deep Is the Ocean? How Deep Is the Ocean? "How Deep Is the Ocean " is a popular song written by Irving Berlin in 1932. The song was developed from an earlier Berlin song "To My Mammy" which was sung by Al Jolson in his film "Mammy" (1930). In the earlier song, the lyrics include the questions "How deep is the ocean? / How high is the sky?" and this was the genesis of "How Deep Is the Ocean?". The song was written at a low point in Berlin's professional and personal life, and is among the select few of his numbers that were