新东方背诵文选 L36.Plate Tectonics and Sea-floor Spreading

The theory of plate tectonics describes the motions of the lithosphere, the comparatively rigid outer layer of the Earth that includes all the crust and part of the underlying mantle. The lithosphere(

新东方优美背诵短文50篇 Unit36:Plate Tectonics and Sea-floor Spreading

The theory of plate tectonics describes the motions of the lithosphere, the comparatively rigid outer layer of the Earth that includes all the crust and part of the underlying mantle. The lithosphere(n.[地]岩石圈)is divided into a few dozen plates o

SSS 2008-08-26

This is Scientific American's 60-Second Science. I'm Adam Hinterthuer. Got a minute? Don't be fooled by those big bovine eyes and the mouth slowly chewing cudcows have a magnetic personality. At least thats the claim made by German researchers in the

考研背诵50篇——36.Plate Tectonics and Sea-floor Spreading

The theory of plate tectonics describes the motions of the lithosphere, the comparatively rigid outer layer of the Earth that includes all the crust and part of the underlying mantle. The lithosphere(n.[ 地 ] 岩石圈 )is divided into a few dozen p

SCIENCE IN THE NEWS - Mars Once Had Moving Plates Like Earth

SCIENCE IN THE NEWS - Mars Once Had Moving Plates Like Earth Has Now By Katherine Gypson, Cynthia Kirk and Karen Leggett Broadcast: Tuesday, November 08, 2005 (MUSIC) VOICE ONE: This is SCIENCE IN THE

科学家们努力了解地球磁场

Scientists Work to Understand Earth's Magnetic Field 科学家们努力了解地球磁场 Most of us rarely think about the earth's magnetic field. We might know that it helps guide birds as they travel and keeps our compasses pointing north. But, th

英语听力：自然百科 地球力场 Earth's Force Field—2

Radiation causes damage at the most fundamental level. It mutates the blueprint of life, DNA. Earth's magnetosphere is our crucial defense. It's so fundamental to our evolution and continued existence that the race is on to understand why it's changi

英语听力：自然百科 地球力场 Earth's Force Field—16

During its magnetic cycle, the Sun undergoes periodic changes in activity. Every 11 years, it enters solar maximum. This 11 years cycle of solar activity has peaks where theres lots of solar storms. And right now where the sun is taking a little napp

英语听力：自然百科 地球力场 Earth's Force Field—12

Six years later, they come to believe these light flashes are the results of high energy, heavy cosmic rays penetrating the spacecraft and the crew members' eyes. These/ protons or electrons, just very, very high energy, ripped / part of atoms, sprin

英语听力：自然百科 地球力场 Earth's Force Field—13

Glatsmire's model shows that the magnetic poles swap places spontaneously due to / complex processes within the core. We were used to the idea that a compass points somewhere near the North Pole and hence we can use it for navigation, but there are p

英语听力：自然百科 地球力场 Earth's Force Field—15

By analyzing thousands of lava samples, geophysicists discover/ that the Earth's magnetic field has reversed over 18,000 times in the last 20 million years. On either side of these reversals is a long period of dramatically reduced field strength. Du

英语听力：自然百科 地球力场 Earth's Force Field—5

If we could flip a switch and just turn off the Earth's magnetic field, it will take about 15,000 years to disappear, based on the rate of decay of the field that we've seen over the last 150 years. It's currently decaying at a rate that would see an

英语听力：自然百科 地球力场 Earth's Force Field—3

In polar regions where the magnetic field is / weakest, auroras glow in the sky. These dazzling displays of colored lights form when solar particles slam into gases in our atmosphere causing them to glow. The stronger the solar wind, the more dramati

英语听力：自然百科 地球力场 Earth's Force Field—4

Scientists believe that the South Atlantic Anomaly, is a sign of a global decline in the magnetic field. Evidence of this comes from a surprising source. Dr. Mimi Hill uses pottery to uncover the secrets of earth's magnetic past. Ancient pots tell us

英语听力：自然百科 地球力场 Earth's Force Field—7

The loss of the magnetic field has a catastrophic impact on the planet's evolution. Mars becomes the red planet we see today. If earths magnetic protection continues to fade, would it suffer the same fate? If it vanishes completely, the planet might

英语听力：自然百科 地球力场 Earth's Force Field—8

Easily confused by this idea, there has a big thawed iron inner core, so that I think it's just the bar magnet, just permanent magnet frozen in nad, and that's where causes all the magnetic field. But it's too hot inside the Earth, that can't happen

英语听力：自然百科 地球力场 Earth's Force Field—9

As the vast sphere reaches / maximum speed, something incredible happens. Huge lines of magnetism arc in and out of the model core. Well, we can't see the magnetic field coming out of the experiment, we can measure them, we can put many different mag

英语听力：自然百科 地球力场 Earth's Force Field—10

Larry Newitt from the Geological Survey of Canada charts the movement of the magnetic North Pole as it wanders the icy reaches of northern Canada. To determine where the magnetic pole / is, we can't rely on one single observation. What I try to do is

万物简史 第258期:大地在移动(12)

but in the 1950s Patrick Blackett of the University of London and S. K. Runcorn of the University of Newcastle studied the ancient magnetic patterns frozen in British rocks and were startled, to say the very least, to find them indicating that at som

双语有声阅读：板块结构与海床扩展

Plate Tectonics and Sea-floor Spreading The theory of plate tectonics describes the motions of the lithosphere, the comparatively rigid outer layer of the Earth that includes all the crust and part of the underlying mantle.The lithosphere is divided