13. Most people like mountains, especially the beings who really belong on Earth
ID: 160538 • Letter: 1
Question
13. Most people like mountains, especially the beings who really belong on Earth. How might mountains remain mountains (high topography) for long periods of geologic time?????_________________________________________________________ __________________________________________________________________________.
14. You pick up a sandstone, which, on the basis of fossils contained in it, you know was deposited in the Cenozoic era, at about 30 million years ago. It has a concentration of detrital zircon grains in it, and ALL of the zircon grains you subject to high precision U-Pb zircon age dating yield age estimates between 30 and 33 million years ago. How might you explain this observation? _____________________________________________________________________ ________________________________________________________________________________.
15. Your “weight” is a direct function of your mass and the mass of Earth, like it or not. If you measured your weight at sea level, above an area in the crust where there is a 10 km diameter buried mass of marshmallow, how would your weight compare to a different site, where there is normal crust below you ? _____________ ___________________________________________ _________________________________________________________ With this as a background, how can gravity be used to investigate the internal structure of our planet? ______________________________________________________________________________
Explanation / Answer
13.
Most of the mountains are formed by the Earth’s tectonic plate crash together. The collision of two continental boundaries or the collision of the oceanic and continental boundaries forms the mountain ranges. At the time of formation of mountain ranges take large amount of sedimentary, some fossil materials, and some amount of igneous rocks. At the time of formation these sediments and rocks tightly bounded and rose to up, due to this reason mountains stable at long period of time.
14.
U-Pb zircon dating is used to find age of the rocks by using zircon crystals in rocks. The age of the rocks are determined by the ratio of Uranium to lead. Zircons are existed in igneous rocks also and these are eroded with sedimentary rocks, and that sedimentary rocks indicate source rock also which means where it came. Here, age of the sandstone is 30 to 33 million years, which gives the ratio uranium and lead and also an indication to source rock.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.