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--------------------------The Earth--------------------------

Ebaluaketa honetan ingelesean “THE EARTH” izeneko proiektua egin dugu. Ostegunetan egiten dugun ingeleseko ikastaroa bhinebi izena du eta egin dugun proiektua bhinebin sartuta dago. Proiektu horretan lurraren atal eta fenomeno batzuk aztertu ditugu eta horri buruz txosten bat egin dugu. Honako atalak ditu:

1. What ’s inside the Earth?=zer dago lurraren barruan? The lithosphere=litosfera.

2. Tectonic plates=plaka tektonikoak. What’s a tectonic plates?=zer dira plaka tektonikoak. Major tectonic plates of the world=munduko plaka

tektoniko handienak.3. Continents=kontinenteak.

Continental drift=kontinenteen aldaketak.4. Earthquakes and volcanoes=sumendiak eta lurrikarak

Informazio guzti hori bilatzeko ostegunetan ordenagailuetara joan gara horretan lan egitera. Eta azkenean talde bakoitzak txosten bat entregatu behar zuen egin duen lana erakutsiz eta hemen duzue gurea:

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1.-WHAT´S INSIDE THE EARTH?.....................................................................3


2.-TECTONIC PLATES………………………………………………………………………………….4




4.-EARTHQUAKES AND VOLCANOES………………………………………………………….9



The lithosphere is the solid part of Earth. It has two parts, the crust and the upper mantle. The crust includes rocks, minerals, and soil. There are two kinds of crust: continental and oceanic. The crust varies from 5 to 70km. Earth’s crust is a thin layer of dense rock about 5km thick. The continental crust is less dense, with lighter-colored rock that varies from 30 to 70 km thick. The continental crust is older.

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This photograph is the earth and there are all the layers. If you see them you can see

the two types of crust: the continental and the oceanic. This is the lithosphere:



Plate tectonics describes the large scale motions of Earth’s lithosphere. The lithosphere plates ride on the asthenosphere. These plates move in relation to one another at one of three types of plate boundaries: convergent or collision boundaries, divergent or spreading boundaries, and transform boundaries. Earthquakes, volcanic activities, mountain-building, and oceanic trench formation occur along plate

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boundaries. The lateral movement of the plates is typically at speeds of 50—100 mm annually.


The lithosphere is broken up into what are called tectonic plates — in the case of Earth, there are seven major and many minor plates

The main plates are:

African Plate covering Africa - Continental plate Antarctic Plate covering Antarctica - Continental plate Australian Plate covering Australia - Continental plate Indian Plate covering Indian subcontinent and a part of Indian Ocean - Continental

plate Eurasian Plate covering Asia and Europe - Continental plate North American Plate covering North America and north-east Siberia - Continental

plate South American Plate covering South America - Continental plate Pacific Plate covering the Pacific Ocean - Oceanic plate

Notable minor plates include the Arabian Plate, the Caribbean Plate, the Juan de Fuca Plate, the Cocos Plate, the Nazca Plate, the Philippine Plate and the Scotia Plate.

The movement of plates has caused the formation and break-up of continents over time, including occasional formation of a super continent that contains most or all of the continents. The super continent Rodinia is thought to have formed about 1 billion years ago and to have embodied most or all of Earth's continents, and broken up into eight continents around 600 million years ago. The eight continents later re-assembled into another super continent called Pangaea; Pangaea eventually broke up into Laurasia and Gondwanaland.

This is the map of the plates tectonics of the world:

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Continental drift is the movement of the Earth's continents relative to each other. As more and more of the seafloor was mapped during the 1950s, the magnetic variations turned out not to be random or isolated occurrences, but instead revealed recognizable patterns. When these magnetic patterns were mapped over a wide region, the ocean floor showed a zebra-like pattern. Alternating stripes of magnetically different rock were laid out in rows on either side of the mid-ocean ridge: one stripe with normal polarity and the adjoining stripe with reversed polarity. The overall pattern, defined by these alternating bands of normally and reversely polarized rock, became known as magnetic striping.

When the rock strata of the tips of separate continents are very similar it suggests that these rocks were formed in the same way implying that they were joined initially.


The hypothesis that the continents once formed a single landmass, broke up, and drifted to their present locations.


The world, its haves a lot of changes, and all the time is in movement.

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Volcanoes are among the most powerful forces in nature. A volcano is a crack or hole in the Earth’s crust, from which molten rock, smoke and gases escape from the mantle, the layer of hot rock below the crust. The molten rock that comes from a volcano is called lava. Magma is the term used for the same hot rocks before they reach the Earth’s surface. When lava comes from a volcano, we say the volcano is erupting. Some kinds of lava are thick and sticky and they solidify quickly into rock. Other kinds of lava are very thin and runny. They can flow for many kilometres before they solidify. This kind of volcanic eruption is much less violent. There are about 500 active volcanoes in the world.

This is a volcano when is erupting:

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When Earth's rocky outer surface moves, we feel it as an earthquake. Each year there are about 50,000 earthquakes around the world, but most can only be detected by delicate instruments.

An earthquake is a sudden movement of the Earth, caused by the abrupt release of strain that has accumulated over a long time. If the earthquake occurs in a populated area, it may cause many deaths and injuries and extensive property damage.

An earthquake is the vibration, sometimes violent, of the Earth's surface that follows a release of energy in the Earth's crust. This energy can be generated by a sudden dislocation of segments of the crust, by a volcanic eruption, or event by manmade explosions. Most destructive quakes, however, are caused by dislocations of the crust.

In the process of breaking, vibrations called "seismic waves" are generated.

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Basic seismograph:

A seismograph detects and records the seismic waves that an earthquake or an explosion generate in the Earth. The illustration shows a seismograph recording vertical movements of the ground. The vibrations produced by earthquakes are detected, recorded, and measured by instruments call seismographs. The zig-zag line made by a seismograph, called a "seismogram,”.Scientists can determine the time, the epicenter, the focal depth, and the type of faulting of an earthquake.

This photo shows one earthquake’s destruction.