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A STUDENT TRIES TO EXPLAIN WHY THERE ARE SEASHELLS ON TOP OF MOUNT EVEREST & THE FORMATION OF THE HIMALAYAN MOUNTAINS JOE REILLY: What do you think? How could a marine fossil get to the top of Mount Everest? TEACHER: I’ve actually heard people talk about this mountain called Mount Everest. Have you ever heard of it? ARIEL: I’ve heard of Mount Everest. JOE REILLY: Fourth-grader Ariel revealed her insights into how Mount Everest might have formed, and how a marine fossil might have gotten to the top. TEACHER: And on top of Mount Everest, there are these rocks. And you know what these rocks have in them? ARIEL: What? TEACHER: Shells. ARIEL: Shells. Oh, I know what that’s from. I know the answer to that one. TEACHER: Okay, let’s talk about it. Tell us about that. ARIEL: Let’s just say...I’ll make this "then and now"-type picture, because we’re showing two time periods. So I’ll draw this to see what happened in between. And at that point, Mount Everest was probably just starting, not at full height. It was a new mountain. And the water was over the top. And in between then and now, the water level dropped and dropped, and Mount Everest kept on growing, too. TEACHER: Okay. So Mount Everest is getting higher the whole time? ARIEL: Yep, as well as the water getting lower. So that’s really doing it. And finally Mount Everest was on dry land, and the biggest mountain in the world. And they would find the rocks with shells in them, because long ago, when that water was there, there were things living in it. There were fish and... TEACHER: How long ago was then, Ariel? ARIEL: The water started to go down in the Ice Age, so I think right here would be the Ice Age. So this is probably maybe during the time of the dinosaurs, and then to the Ice Age, the Ice Age, with the freezing, the water began to go down. Sometimes those icebergs would get so heavy that they’d just sink, and the water level was brought down to where it is today. And then little creatures like these, they’d find rocks which have fossils of them inside. And then probably at the top of Mount Everest, maybe some of those were there, and they died up there, and were near the mountain rock, of course, for many years, and then they found these rocks which have the fossils in them. TEACHER: Okay. And can you tell me how many years ago... JOE REILLY: Scientists have evidence that throughout the Earth’s history, sea level has risen and fallen several times. There is also evidence that huge underwater mountains, taller than Everest, exist on the sea floor today. Ariel believes that a decrease in sea level exposed Mount Everest to the open air, leaving marine life on top of the mountain to die and eventually fossilize. Do you think this is how a marine fossil made its way to the top of Mount Everest? BRITT ARGOW: I think that we can finally solve the Mount Everest mystery: how marine fossils got to the top of the world’s tallest mountain. Now, the Himalayas are located here, along the border between India and China. These mountains mark the boundary between the IndianAustralian plate and the Eurasian plate. Now, both plates are moving in the same direction, but the Indian-Australian plate is moving faster than the Eurasian plate. REILLY: So here are the two plates, and they’re moving in the same direction, but India’s moving faster. So at some point, it pretty much rear-ends the Eurasian plate. ARGOW: Exactly. Now, scientists believe that 40 million years ago, the Indian plate was not attached to the Eurasian plate. Instead, they were separated by a region of oceanic crust. Now, as these plates continued to move, India was moving faster, and about 40 million years ago, it caught up and slammed into the Eurasian plate. As the plates collided, the Himalayan mountain range was born. And this collision is continuing even today. So every single year, these mountains are driven a little bit higher. REILLY: And I can imagine that before the continents collided, there was an ocean between them. And somewhere in that ocean, marine critters lived and died, and their shells were fossilized in the sediments of the sea floor. Then, when India finally collided with Asia, that fossil got driven up with the rest of the continental crust. And over millions of years, it was pushed up some 30,000 feet to the top of the world.