TO REMEMBER WHY WE CELEBRATE LABOR DAY: "If you think that hanging can kill the labor movement ... the movement of which the downtrodden millions, the millions who work in poverty and the need to wait for their salvation, if this is your opinion, then ahórcanos! Here trample a spark, but here and there, behind you, before you, and everywhere, flames will emerge. It is a fire underground. You can not put out. " Albert Spies (executed in Chicago on November 11, 1887)
· It extends from the origin of the Earth (4600 million years ago) to 570 million years.
• This period covers more than 80% of geological time.
· There several masses of continental crust that were grouped to form the "Pangea 1."
• This period is divided into two stages:
- ARCHAIC
* From the origin of the Earth up to 2500 million years ago.
° is rocks 3800 million years.
· The rocks of this period can be found in the mountains. Rocky Canyon and in stable areas of the interior of continents.
- Proterozoic
· from for 2500 to 570 million years. • Between
for 1700 and 1000 million years, igneous intrusion occurs. • Also
continental expansion occurs and the grouping of continetes where Pangea is fragmented by creating the North American continent and Europe. PALEOZOIC
· It extends for 2500 and 570 million years
· Start with the fragmentation of Pangea 1 of Precambrian form a large number of dispersed continents, who returned to collide with each other, creating mountain ranges or orogens.
· It is divided into six periods: Cambrian, Ordorícico, Silúrgico, Devonian, Carboniferous and Permian.
- Cambrian
· For 570 to 500,000,000 years. · It breaks the supercontinent called Pangea.
- ORDOVICIAN
· From 500-430 million years.
- SILURIAN AND DEVONIAN
· from 430 to 395,000,000 years ago, and from 395 to 345 miles. years. · It will form the "orogeny Caledon" resulting in the Appalachians and Caledónides and the Iapetus Ocean between Laurentia and Baltica plates.
• Almost at the same time as the Iapetus disappears, causing Arctic America hits the orogen Franklin, located in northern Canada, Greenland and Siberia.
- Carboniferous
· For 345 and 280 million years. · It will form the "Hercynian orogeny.
· We create new wetlands that later formed deltaic forests.
· It is the ocean between the plates Paleotetis Harmonica and Gondwana.
• Also it creates part of the Iberian Peninsula.
- PERMIAN
· For 280 to 225 mill. years.
· It reunites the great continent of Pangea 2.
· The masses called Siberia, hit Amunia Kazaskstania and Laurasia, resulting in the Urals and Verhojansk. Mesozoic
- TRIASSIC
· For 225 to 190 mill. years.
- JURASSIC
· For 190 to 135,000,000 years.
· It is increasingly opening up the Atlantic and Indian Oceans, "Pantalasa" shrinks and gives way to the Pacific Ocean.
· North America separated from Africa, India, Africa and Antarctica, Australia and Antarctica and Africa.
• The "Thetis" begins to close, the associated compression will result in the formation of a series of mountain ranges along its edges.
• At the end of the Jurassic, South America and Africa began to separate. In the middle of both continents are deposited sediments, first and then later marine environment.
- CRETACEOUS
· For 135 and 65 miles. years.
complete separation · The Africa-South America. During the initial stages of the opening of the South Atlantic is intense evaporation.
• The Mid-Atlantic Ridge is diverted from the West Greenland to the East.
• The displacement and counterclockwise rotation of Africa and turning clockwise as the Eurasian plate close the eastern end of Tethys.
· A except for Greenland and Europe on one side and Australia and Antarctica on the other, all the continents are separated.
· A late Mesozoic orogeny occurs called "Alpine" leading to the Alpine ranges. CENOZOIC
· from 65 million years ago until today. · We are the large current ranges (Alps, Himalayas, Andes, Rocky Mountains)
• The Mediterranean dried up. • The India and Africa continue their journey north and will collide with the Eurasian continent.
· It is divided into two periods.
- TERTIARY
· For 65 to 2.5 mill. years.
· Latin America North and South are linked by the formation of the Isthmus of Panama.
• The India completes its translation to the north collided with the Asian plate resulted in the Himalayas.
· Australia separated from Antarctica and began his translation to his current position.
· Separation final of Europe and North America in the Paleógeneo.
· Oligocene marine transgression which reduces Europe on an island. In the Miocene the sea recedes, which is the maximum period of emersion.
• The Mediterranean Sea acquired its current configuration.
· Separation of South America and Antarctica through the opening passage of "Drake"
· It is divided into 5 stages in other smaller.
- Paleocene
· For 65 to 55 mill. years.
· Separation final of Europe and North America.
- EOCENE
· For 55 to 38 mill. years.
• Between this and the next stage produces the "Pyrenean stage" resulting in the Pyrenees and outlines the rest of the European apinan chains.
- Oligocene
· For 38 to 26 mill. years.
· Phase Pyrenees.
• Between this stage and the next there is the "phase Savica" being the main thrust tectonics of the Alpine orogeny. He formed the mountains of Atlas, Betic, Alps, Himalayas and the Caucasus, among others.
- MIOCENE
· For 26 to 6 mill. years.
· Phase Savic.
· At the end of this stage occurs "Rodan stage."
- PLIOCENE
· For 6 to 2.5 mill. years.
- QUATERNARY
· For 2.5 mill. of years until today.
• It is the shorter period that exists now. GLOSSARY
· Pangea: Name proposed by Alfred Wegener to the existing supercontinent at the end of Paleozoic and which included all land masses.
· Orogeny Caledon: A set of processes and tectonic movements that create a new mountain range. This affected Greenland, Scotland and Europe.
· Hercynian Orogeny: The most important Paleozoic orogenic, since it is the union of most of the continental masses in the supercontinent Pangea 2, which caused the deformation of the material occupying the Bight (Proto-Tethys) between a set northern (Laurasia) and one southern (Gondwana). It can be seen in Europe, Africa and North America.
· Alpine Orogeny: The rocks of this time interval occupy 80% of the area. In some areas has revived recycled materials made in other orogenic cycles, deformed and metamorphosed, erasing the tracks from older orogenies.
· Tethys: the space now occupied by the peninsula was invaded by a vast sea that connected the Atlantic and the Mediterranean called the Tethys Sea.
· Drake: Antarctica is clear from Patagonia by the opening of Drake Passage.
· Phase Pyrenees: phase leading to mountains like the Pyrenees.
· Phase Savica: phase leading to mountains and mountain ranges like the Atlas, Betic, Alps, Himalayas and Caucasus inter
· Phase Rodan: phase leading to mountains and corresponds with the posthumous folding occurring during the late Miocene . (Http://html.rincondelvago.com/periodos-geologicos.html)
