The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into tectonic plates. The Earth's lithosphere is composed of seven or eight major plates (depending on how they are defined) and many minor plates. Where the plates meet, their relative motion determines the type of boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually.[2]
Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the lithosphere remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories, since disproven, proposed gradual shrinking (contraction) or gradual expansion of the globe.[3]
Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.
Mexico has the greatest number of diversity of animals and plants. That's why its an megadiverse country.
Answer:
9,240
Explanation:
This company makes 840 notebooks in 1 day. 840 x 11 = 9,240
Answer:
All dinosaur fossils found by archeologists have been found a few centimeters below the iridium layer. So, the possibility of finding dinosaur fossils above the iridium layer is very slim.
Explanation:
Over 65 million years ago, dinosaurs roamed the earth but were canceled out as a result of an extraterrestrial impact on the earth's crust. Research proved that an asteroid brought the end of dinosaurs as the element iridium was found in the earth (since iridium is abundant in asteroids and not the earth's crust).
Records of fossils found have been between 13 to 60 centimeters below the iridium or the K-T boundary as it is called.
Answer:
C. Russia
Explanation:
According to land area it is the largest country