Geography - note World, in 24 editions.

the world is now thought to be about 4.55 billion years old, just about one-third of the 13-billion-year 13.7-billion-year age estimated for the universe

the world is now thought to be about 4.55 billion years old, just about one-third of the 13.7-billion-year 13.75-billion-year age estimated for the universe

the world is now thought to be about 4.55 billion years old, just about one-third of the 13.75-billion-year 13.8-billion-year age estimated for the universe

note: note 1: the world is now thought to be about 4.55 billion years old, just about one-third of the 13.8-billion-year age estimated for the universe note: universe; the earliest widely accepted date for life appearing on earth is 3.48 billion years ago, but this date is conservative and may get pushed back further note 2: although earthquakes can strike anywhere at any time, the vast majority occur in three large zones of the earth; the world's greatest earthquake belt, the Circum-Pacific Belt (popularly referred to as the Ring of Fire), is the zone of active volcanoes and earthquake epicenters bordering the Pacific Ocean; about 90% of the world's earthquakes (81% of the largest earthquakes) and some 75% of the world's volcanoes occur within the Ring of Fire; the belt extends northward from Chile, along the South American coast, through Central America, Mexico, the western US, southern Alaska and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, island groups in the southwestern Pacific, and New Zealand
the second prominent belt, the Alpide, extends from Java to Sumatra, northward along the mountains of Burma, then eastward through the Himalayas, the Mediterranean, and out into the Atlantic Ocean; it accounts for about 17% of the world's largest earthquakes; the third important belt follows the long Mid-Atlantic Ridge

note 1: the world is now thought to be about 4.55 billion years old, just about one-third of the 13.8-billion-year age estimated for the universe; the earliest widely accepted date for life appearing on earth is 3.48 billion years ago, but this date is conservative and may get pushed back further
note 2: although earthquakes can strike anywhere at any time, the vast majority occur in three large zones of the earth; the world's greatest earthquake belt, the Circum-Pacific Belt (popularly referred to as the Ring of Fire), is the zone of active volcanoes and earthquake epicenters bordering the Pacific Ocean; about 90% of the world's earthquakes (81% of the largest earthquakes) and some 75% of the world's volcanoes occur within the Ring of Fire; the belt extends northward from Chile, along the South American coast, through Central America, Mexico, the western US, southern Alaska and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, island groups in the southwestern Pacific, and New Zealand
the second prominent belt, the Alpide, extends from Java to Sumatra, northward along the mountains of Burma, then eastward through the Himalayas, the Mediterranean, and out into the Atlantic Ocean; it accounts for about 17% of the world's largest earthquakes; the third important belt follows the long Mid-Atlantic Ridge

note 1: the world is now thought to be about 4.55 billion years old, just about one-third of the 13.8-billion-year age estimated for the universe; the earliest widely accepted date for life appearing on earth is 3.48 billion years ago, but this date is conservative and may get pushed back further
note 2: although earthquakes can strike anywhere at any time, the vast majority occur in three large zones of the earth; the world's greatest earthquake belt, the Circum-Pacific Belt (popularly referred to as the Ring of Fire), is the zone of active volcanoes and earthquake epicenters bordering the Pacific Ocean; about 90% of the world's earthquakes (81% of the largest earthquakes) and some 75% of the world's volcanoes occur within the Ring of Fire; the belt extends northward from Chile, along the South American coast, through Central America, Mexico, the western US, southern Alaska and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, island groups in the southwestern Pacific, and New Zealand
the second prominent belt, the Alpide, extends from Java to Sumatra, northward along the mountains of Burma, then eastward through the Himalayas, the Mediterranean, and out into the Atlantic Ocean; it accounts for about 17% of the world's largest earthquakes; the third important belt follows the long Mid-Atlantic Ridge
note 3: information on the origin sites for many of the world's major food crops may be found in the "Geography - note" for the following countries: Argentina, Bolivia, Brazil, China, Ecuador, Ethiopia, Indonesia, Mexico, Papua New Guinea, Paraguay, Peru, and the United States

note 1: the world World is now thought to be about 4.55 billion years old, just about one-third of the 13.8-billion-year age estimated for the universe; the earliest widely accepted date for life appearing on earth Earth is 3.48 billion years ago, but this date is conservative and may get pushed back further
note 2: although earthquakes can strike anywhere at any time, the vast majority occur in three large zones of the earth; Earth; the world's greatest earthquake belt, the Circum-Pacific Belt (popularly referred to as the Ring of Fire), is the zone of active volcanoes and earthquake epicenters bordering the Pacific Ocean; about 90% of the world's World's earthquakes (81% of the largest earthquakes) and some 75% of the world's World's volcanoes occur within the Ring of Fire; the belt extends northward from Chile, along the South American coast, through Central America, Mexico, the western US, southern Alaska and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, island groups in the southwestern Pacific, and New Zealand
the second prominent belt, the Alpide, extends from Java to Sumatra, northward along the mountains of Burma, then eastward through the Himalayas, the Mediterranean, and out into the Atlantic Ocean; it accounts for about 17% of the world's largest earthquakes; the third important belt follows the long Mid-Atlantic Ridge
note 3: information on the origin sites for many of the world's World's major food crops may be found in the "Geography - note" for the following countries: Argentina, Bolivia, Brazil, China, Ecuador, Ethiopia, Indonesia, Mexico, Papua New Guinea, Paraguay, Peru, and the United States

note 1: the World is now thought to be about 4.55 billion years old, just about one-third of the 13.8-billion-year age estimated for the universe; the earliest widely accepted date for life appearing on Earth is 3.48 billion years ago, but this date is conservative and may get pushed back further ago
note 2: although earthquakes can strike anywhere at any time, the vast majority occur in three large zones of the Earth; the world's greatest earthquake belt, the Circum-Pacific Belt (popularly referred to as the Ring of Fire), is the zone of active volcanoes and earthquake epicenters bordering the Pacific Ocean; about 90% of the World's world's earthquakes (81% of the largest earthquakes) and some 75% of the World's world's volcanoes occur within the Ring of Fire; the belt extends northward from Chile, along the South American coast, through Central America, Mexico, the western US, southern Alaska and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, island groups in the southwestern Pacific, and New Zealand
the second prominent belt, the Alpide, extends from Java to Sumatra, northward along the mountains of Burma, then eastward through the Himalayas, the Mediterranean, and out into the Atlantic Ocean; it accounts for about 17% of the world's largest earthquakes; the third important belt follows the long Mid-Atlantic Ridge
note 3: information on the origin sites for many of the World's world's major food crops may be found in the "Geography - note" for the following countries: Argentina, Bolivia, Brazil, China, Ecuador, Ethiopia, Indonesia, Mexico, Papua New Guinea, Paraguay, Peru, and the United States