Lesson 30 :Fossiles,The Grand Canyon, and Rock Layers

Fossils 

 Fossil means something dug up, a fossil was an animal  that was formerly living but then got buried suddenly. Paleontologists are people who study fossils, organisms harden into fossils under the right circumstances. Fossils can occur quickly in flood like conditions.an example of a fossil is petrified wood it is fossilised by minerals replacing the tissue of the wood.

The grand canyon

the Grand Canyon

Since no human witnessed the formation of the grand canyon no one can prove their theory. Today radioactive dating is used to assign relative dates to start layers in the canyons. Radioactive dating is when elements like carbon decay or lose options . If carbon has too many neutrons it will become unstable, unstable atoms will lose particles and become stable. Scientists can observe the time required for half of the unstable atoms to become stable; this is called half-life. Scientists know the present decay of an individual atom like carbon.the decay rate functions like a stopwatch ticking.

Transcontinental rock layers

There are 6 mega sequences of rock layers; all six are visible in the grand canyon. All of these layers are layered out through north america . these layers were discovered about 50 years ago. 

Essay Lesson 25 : Mountains Glaciers and Deserts

There are lots of mountain ranges around the world, one of them is the ural Mountains . The Ural mountain is 1,550 ft. long and 20-90 miles wide. The Ural mountain range is the boundary between Europe and Asia.

Oragany

Oragany is the creation of mountains which is built from the converging plate zone. There are three of these convergence the first is the ocean continent convergence. An example of this is the nazca plate going under the south american plate. The second is the arc-continent convergence this is when an island collides into a continental plate. The last on is the continent- continent convergence this is when two continents collide and the folded crust gets pushed in.

Glaciers

Glaciers can erode through mountains it is one of the primary ways mountains and land formations are eroded. Glaciers are formed by snow that is compacted together. Glaciers leave back sediment once it is melted.

Deserts 

Deserts can be hot and cold it just depends on whether it got 24 centimeters of water per year. Deserts tend to form 30 derges south and north of the equator this is because air et compressed and sucks up the moisture. That is why we have dry regions such as the sarharh desert.and oolong the equator human air drops and expand then gets cooler and persipitates  more. Deserts tend to have dry stream beds.

Essay Lesson 11: Earth’s Crust

The earth’s crust is divided into two crusts one being the continental crust and the other being the oceanic crust.The continental crust is 18.6-31 miles miles thick, and it is primarily composed of felsic rock.The primary rock found on the earth’s crust is the granite and igneous rock.Granite is an example of igneous rock once it cools.Then there is oceanic crust which is 4.3 miles thick and is primarily composed of mafic rock. Mafic rock contains magnesium and iron.There is basalt and gabbro rocks, basalt is a volcanic rock it comes through volcanoes.Even though the oceanic crust is thinner it is more dense.No machine has ever been able to drill a hole through the earth crust.One Russian group drilled at the Kola Super deep Borehole and the made it 40,230 ft below the surface which is the deepest hole there has ever been.  

Essay Lesson 20: Volcano’s

the ring of fire


There are major characteristics that can tell a volcano from a mountain. Volcanoes have a vent that lends to the hot spot or magma chamber.There are different types of volcanoes, the first is the shield volcano. Shield volcanoes will gradually slope up . shield volcanoes tend to be non violent in their eruptions because it has fluid like lava. The shield volcanoes are primarily located near the hawian emperor seamount chain area. Another type of volcano is composite volcanoes. Composite volcanoes erupt violently; these are probably the most famous types of volcanoes. They erupt very violently because of its thick lava. They are primarily located along the circum pacif belt/the ring of fire. And then there are cinder cone volcanoes; these are smaller than most volcanoes; they are located on shield volcanoes. And the last volcano type is lava domes. And they erupt extremely violently because they have very patsey lava. And they often form in composite volcano craters.

Essay Lesson 15 : Earth’s interior

The earth’s  crust, mantle, and core 

The earth’s crust is divided into two crusts one being the continental crust and the other being the oceanic crust.The primary rock found on the earth’s crust is the granite and igneous rock.The continental crust is 18.6-31 miles miles thick, and it is primarily composed of felsic rock.Then there is oceanic crust which is 4.3 miles thick and is primarily composed of mafic rock.Mafic rock contains magnesium and iron.even though the oceanic crust is thinner it is more dense.No machine has ever been able to drill a hole through the earth crust.

The earth’s mantle is mostly solid there are areas in the mantle that has semi melted rock also none as magma chambers and the upper mantle possible consists of ultramafic rock which is  very dense igneous rock the crust and the upper mantle are the lithosphere which is the earth’s plates that move on the earths the lower layer  under the lithosphere is the asthenosphere scientists believe this is a slushy area some of the rock is crystals and the others are liquid  

The earth’s core seismic waves do not appear on the other side of the earth the shadow zone. S waves are the epicenter of an earthquake .Seismologists know that the S waves don’t go through the center of the earth so there is a shadow zone where the seismologist don’t see the occurrence of the s waves. P waves go in other directions like S waves but they start going through the core then start refracting and bending and then start to bend. Even though there are still shadow zones . It is a scientific fact that the core is more dense and is metal.

Earth’s  magnetic shield

The north pole is magnetic south and magnetic north is the south pole. The reason a magnet needle points to the north pole/magnetic south is because the earth is a giant magnet. With magnets opposites attract but if you put both north sides together they will repeal the reason is because the magnetic force that is generated is going the same direction so they are repelled. A compass has a lightweight magnet inside that points to the earths north pole.The magnet picks up the earth’s magnetic field . The earth’s tilt is 11.5 degrees because North is actually 11.5 degrees from south  

Earth’s floor

Evidence suggests that the earth’s plates have moved a lot since the begging of time. These earth plates move from 0.5 to 6in per year. There are ocean floor ridges that indicate that on both sides of the earth’s floor are moving. As the seafloor is expanding there are magma chambers that create more rocks once it cools but it shrinks along the seafloor then it goes under the continental plate and creates mountains. The plate goes down and starts to melt and it goes through the mantle and starts all over again 

Earthquakes

An earthquake is a movement alongside boundaries or faults. A fault is a break between rocks. An earthquake is a sudden occurrence of released energy that has been stored. Earthquakes normally occur deep inside the earth sometimes 435 miles deep mostly near the crust. There are three different faults the first is a strike slip fault 2 rocks grind past each other . The second is a normal fault where 1 rock slides down into the ocean ridge. The third is reverse fault where two rock collide into each other.

Essay lesson 10: Earth Materials

Earth is made up of rocks and rocks are made from minerals. Those minerals are made up of elements. Some of these minerals have two or more elements but some minerals only have one.

Minerals

 Minerals must naturally occur; it has to be earth made to be a mineral. They are not real if a scientist makes it. Minerals are inorganic which means they are dead. Minerals are crystalline  which means their atoms are formed together to make a 3D form. Minerals are solid which means they stay stable at room temperature. Many minerals have only two elements like salt .

Mining 

Mining  can be very dangerous like in 2010  lots of people got stuck in a mine but they all got out safely . There are three different mining methods: the first is underground mining.underground mining when they mine precious metals like gold ,silver and platinum. underground mining is very expensive so they have to get great value. Surface mining is the second major type of mining; it is less expensive and often base metals and minerals can be extracted from the surface. The third is placer mining often metals can be separated from sediment in rivers  or streams .There is a tool called the slooce trap that saves valuable  material and separates it from sediment .

Essay Lesson 5: Geology Rocks

The three major types of rocks

1.  Igneous rocks

The first type of igneous rocks are volcanic rocks; they have basalt, vesicles (small holes), and microscopic crystals. The second one is plutonic; they are made of granite and big crystals.

2.  Sedimentary rocks

The first type of sedimentary rocks are shale rock; they are composed of mud and parallel layers the second is sandstone ;sandstone is composed of quartz and can be any color. 

3.  Metamorphic rock: The metamorphic  rocks change form they can be foliated which means they have a texture or they can be no foliated which means they do not have a texture.  The rock cycle 

The rock cycle starts with weathering this is when wind or rain transports rock from mountains and cliffs into streams, rivers or lakes. Then these rivers deposit the boulders or bigger rocks to a delta . Those rocks will get pressured from more rocks that are being pushed on top of them. Then the rocks go deeper into the earth’s crust and start to heat up. They will then start to melt and turn into lava. Once it turns into lava it will uplift slowly or fast  through a volcano . Once it cools ,the process all over again.They don’t have to happen in this order or sometimes they will only have a few of these steps completed.