OCS Homework

OCS Homework - Erin Riche OCS Section -1 January 29, 2012...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Erin Riche OCS Section -1 January 29, 2012 Chapter Two 2. Cite the lines of evidence Alfred Wegener used to support his idea of continental drift. Why did Scientists doubt that continents drifted? Alfred Wegener “envisioned that the continents were slowly drifting across the globe and called his idea continental drift” (Thurman pg 35). “Wegener suggested that during the geologic past, the continents collided to form a large landmass, which he named Pangaea (…) Wegener’s evidence indicated that as Pangaea began to split apart, the various continental masses started to drift toward their present geographic positions” (Thurman pg 36). Wegener also attempted to match up the shoreline and found crustal overlap and large gaps so many other scientists did doubt Wegener’s theories. Also they tested his theory and geologist began comparing the rocks along the edges of continents with rocks found in adjacent positions o matching continents. They wanted to see if the rocks were similar at all. And their findings were that adjacent continents in fact, did match up. Another one of Wegener’s theory was the fact that organisms such as Mesosaurus were found only on adjacent continents, which could mean that they were once connected. Other Scientists did not accept Wegner because “he suggested the continents plowed through the ocean basins to reach their present-day poitions and that the leading edges fo the continets deformed into mountain ridges because of the drag imposed by ocean rocks. Further, the dribing mechanism he proposed was a combination of the gravitational
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
attraction of Earth’s equatorial buldge and tidal forces from the Sun and Moon” (Thurman, pg 39). Many Scientists thought that this theory was not correct. Instead the ocean floor was a conveyer belt that was being continuously formed at the mid-ocean ridge and destroyed at the trenches, with the continents just passively riding along on the conveyer. 3. Describe Earth’s magnetic Field, including how it has changed through time. Earth’s magnetic field is generated by molten (liquid) iron and it is the shield from the Sun and other harmful elements that may attack Earth at any moment. Thus, making it Earth’s force field. Because the sun does throw off electric charged particles we need this magnetic field for protection. If we do loose this magnetic field then we are put at danger and we have no protection from all the radiation that is penetrating Earth. The magnetic field is cooling 100 degrees per billion years due to our habits on the Earth that harms our magnetic field. This is still very slow rate of cooling, but if it continues then we will loose it all together. The magnetic field keeps changes every 100,000 years and flips the direction in which it is going. It has changed over the years by which direction it is going. This is caused by the Earth’s polarity reversing magnetic poles.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 10

OCS Homework - Erin Riche OCS Section -1 January 29, 2012...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online