How deep does sea level drop during an ice age?
Regional Specificsabout 400 feet400 feet (122 meters) lower than today. During the last global “warm spell,” about 125,000 years ago, the seas were about 18 feet (5.5. How much does sea level drop during an ice age? During the most recent ice age (at its maximum about 20,000 years ago) the world’s sea level was about
What do shallow earthquakes mean?
Regional SpecificsMost parts of the world experience at least occasional shallow earthquakes—those that originate within 60 km (40 miles) of the Earth’s outer surface. In fact, the great majority of earthquake foci are shallow. What do shallow earthquakes indicate? Earthquakes are labeled “shallow” if they occur at less than 50 kilometers depth. They are labeled “deep”
Which is stronger magnitude or intensity?
Regional SpecificsMagnitude and Intensity measure different characteristics of earthquakes. Magnitude measures the energy released at the source of the earthquake. Magnitude is determined from measurements on seismographs. Intensity measures the strength of shaking produced by the earthquake at a certain location. Which is higher magnitude or intensity? Magnitude is a measure of earthquake size and remains
How are neritic sediments different from pelagic sediments?
Natural EnvironmentsNeritic sediments cover about ¼ of sea floor and are near landmasses. The term pelagic means “of or relating to the open sea” particularly the upper layers of the ocean away from shore. Pelagic sediments are generally deep-water deposits mostly oozes (see below) and windblown clays. What is the difference between neritic and pelagic deposits
Why does the continental crust rise higher than the oceanic crust?
Regional SpecificsThe less-dense continental crust has greater buoyancy, causing it to float much higher in the mantle. Its average elevation above sea level is 840 metres (2,750 feet), while the average depth of oceanic crust is 3,790 metres (12,400 feet). This density difference creates two principal levels of Earth’s surface. Why is the oceanic crust lower
How many eras have there been?
Regional SpecificsTen eras are recognized by the International Union of Geological Sciences: the Eoarchean Era (4.0 billion to 3.6 billion years ago), the Paleoarchean Era (3.6 billion to 3.2 billion years ago), the Mesoarchean Era (3.2 billion to 2.8 billion years ago), the Neoarchean Era (2.8 billion to 2.5 billion years ago), the … What are