South America Timeline

Life In South America

During the Pre-Cambrian era, life in South America was in its early stages. Microbial life and simple single-celled organisms likely thrived, laying the groundwork for the evolution of more complex life forms that would emerge in the following geological eras. Evidence from fossil records in the Pre-Cambrian era shows that life was very primitive , consisting of photo-synthetic bacteria, primitive marine plants and single-celled organisms . Some of these single-celled organisms were Trilobites, Brachoipod, and Pikaia.

Life in South America

Model of South America

Model of South America

In the model it shows South America before in the Pre-Cambrian era. In the second piece of the model shows South America's current position on Earth.

Plate Boundary

As the two plates of the South American and Nazca plate move toward each other, the Nazca plate sinks under the South American Plate. Eventually the Nazca Plate sinks into the mantle being destroyed, which could result in mountin ranges.

During the Pre-Cambrian era, the formation of supercontinents, such as Rodinia and Pangea was made up of plate boundaries. The formation of South America is from the plate motion, of plate boundaries being moved by the convection currents in the mantle that moves the plates. As the plates are being seperated from each other creating gaps in the earth, then being filled with magma in the mantle, hardening creating new crust to the edges of the South American Plate. This process is a key component of plate tectonics, contributing to the movement of continents on the Earth's surface.

Plate Boundary

Geography

Geography

During the Pre-Cambrian era, South America's geography was vastly different from what it is today. It was part of the supercontinent Rodinia and had a different position and shape due to the movements of tectonic plates. The landmasses were merging and separating, playing a crucial role in the early geological formation of South America, setting the stage for its future geographical elements. In South America's geography there were cratons, andean ranges, and basins, which shaped most of the margins of South America.

Fossils and Rocks Evidence

Fossils and Rocks

The Pre-Cambrian was the start of life on Earth. Speices included were mostly single-celled animals and plants. The plants in this era produced coal. These coal deposits are formed in tropical climates that are warm and wet. But coal has also been found in Alaska which is a cold environment. The discoverment of coal deposits being found in Alaska which is a cold environment shows evidence that the continents have moved over time.

Life and Climate

During the Paleozoic period, many animal species and plant life had sprung up. Tribolites and Graptolites had came into existence and were found in the lower part of the Andes. Climate during the Paleozoic period consisted of a variety of unique climates. Most of south america had a warm climate, however, the northern coast of South America suffered from cold weather.

Life During the Time Period

Plate boundaries

Plate Boundaries

South America had both convergent and divergent plates. An example of one of them would be the South American plate diverging from the African plate. When seen on a map, a divergent boundary between both plates can be seen. The process of divergence occurs due to the process of sea floor spreading. Effects of sea floor spreading can be viewed in the Mid-Atlantic ridge. At the end of the Paleozoic Era, the world had become a megacontinent making Pangea in the process. When Swaziland and Laurasia had combined, it had created the megacontient known as Pangea. During this period, the South American plate was surrounded by the North American, African, and Nazca plates to the North, East, and West respectively

Plate Movement

The ending of the Paleozoic period had ended with Gondawaland merging with Laurasia to create the megacontinent of Pangea. The changing landscape had led to Pangea to stop subduction in it's western part. This had later led to the Andes mountains being made during the Cenazoic times.

Plate movement happens when two plate either diverge, transform, or converge. In the case of South America, convection is a process that pulls plates apart. The idea of density can be tied into convection. Leading to the continents splitting apart. This being the same as Pangea and the multiple continents that split apart over a process of millions of years. As previously stated, sea floor spreading occurs when two plates spread apart, causing magma to rise from the mantle creating new crust in the earth.

Plate Movement

Geography

Geography

The Paleozoic Era was somewhat near a modern version of the earth. Rocks found in the area were dated from the Paleozoic Era which showed the breakup of Gondawaland. The split in South America had led to the creation of many basins in the continent including but not limited to the Amazonas, Chaco, and Parana basins. Belts from the subduction of the era had led to the creation of the Patagonain mountains. Sedimentary rock found in the area was dated from the same time as the creation of the Karoo basin located in Southern Africa. These basins originated from the former microcontinent Patagonia hitting Gondawaland creating the basins found in both South America and South Africa.

Model

Life In South America

During the Mesozoic Era, South America was connected with Africa. South America's climate throughout the era, was moderately warm with an abundant amount of rainfall. South America had multiple basins which helped provide water to the animals living there. South America also had animals such as dinosaurs, marine reptiles, lizards, and tortoises. The Mesozoic Era was a time of the reptiles so these animals which were ruling in South America. There were many rainforests and the land was very rich. Overall, South America during the Mesozoic Era was a time of humid climate and reptiles

Life in South America

How Do Plates Move?

Continents move due to the mantle that is underneath their plates. Africa and South America moved due to the oceanic divergent plates that moved apart. These two plates are called the South American Plate and the African Plate. Plates move due to the temperature transferring between the material in the mantle. In the mantle, there is cold material and hot material. The colder material becomes more dense and sinks to the bottom of the mantle. However, it then gets heated up by the core and that makes it less dense letting it rise. This motion keeps on happening creating convection currents. This whole process is called convection which occurs in the mantle causing the plates on top of the mantle to move. When the convection currents move ina certain divergent plates move. When divergent plates move, they move away from each other causing the soft solid rock from underneath to rise and hard to add solid rock to the edges of both plates.

South America's Plate Movement

Mid Ocean Ridges/Seafloor Spreading

When two oceanic plates move away from eachother a phenomenom called sea floor spreading occurs. As two oceanic plates move apart, the rock from the mantle rises and adds new crust onto the rocks. This means that the farther the crust is from the plate boundary the older is. When South America and Africa moved apart sea floor spreading occured and we can see this with the crust that is near South America and Africa. The crust near these two continents are about 180 million years ago, which was during the Mesozoic Era. This means that these two continents separated during the Mesozoic Era around the Triassic Period. When divergent plate boundaries move apart landforms are also created. When South America and Africa moved away from eachother, a mid ocean ridge was formed, called the Mid - Atlantic Ridge. The Mid - Atlantic Ridge is a underwater volcanic chain and is still growing to this day.

Landforms/Seafloor Spreading

Mid Atlantic Ridge

Sea floor spreading, due to divergent plates in Africa and South America.

Fossils and Rocks Evidence

During the Mesozoic Era, South America and Africa were once connected. Fossils of the Mesosaurus can help us prove this. This freshwater-swimming reptile has fossils that are found on both continents. Now, there is a vast ocean between Africa and South America separating the two continents. The Mesosaurus could not travel that far and could not swim in ocean water, meaning that the continental drift of South America and Africa separated the fossils. Another piece of evidence is that there are similar rock types of the same age found on the east side of South America and the west side of Africa. These rock types were metamorphic rocks and were formed at around the same time (540 Ma). This shows that these rocks were the same, and were formed near eachother. However now there is an entire ocean separating these rock types. These rock types cannot travel across the ocean, due to how heavy they are which means that these continents must have traveled apart to separate these rock types.

Fossils and Rocks

Model

Model

How South America looked before and after

Plate Boundary

During the Cenozoic era, South America experienced various plate boundary interactions. The most significant one was the creation of the Andes Mountains due to the subduction of the Nazca Plate beneath the South American Plate along the western coast. This tectonic activity led to the creation of the mountain range that takes up much of South America's western region.

Plate motion occurs due to the movement of tectonic plates, which float on the mantle beneath earth's crust. This movement is driven by the transfer of heat from the Earth's interior, causing convection currents that can push the plates apart, collide, or slide past each other. Sea floor spreading is a process where new oceanic crust is formed at mid-ocean ridges as two tectonic plates move away from each other. Magma rises from the mantle, solidifies, and creates new crust, pushing the older crust away from the ridge. This process is a key component of plate tectonics, contributing to the movement of continents on the Earth's surface.

Plate Boundary

Life in South America

During the Cenozoic era, South America consisted of a wide variety of wildlife. The continent contained a variety of unique creatures, including giant ground sloths, saber-toothed cats, and large flightless birds known as terror birds. The changing landscapes and environmental shifts encouraged the evolution of different ecosystems, fostering a wide range of flora and fauna. These factors contributed to South America becoming a region known for its biodiversity.

Life in South America

Fossils and Rocks Evidence

Fossils and Rocks

The discovery of similar fossils and rock formations on two different continents provides evidence for the theory that South America moved over time. Identical or matching fossils and geological structures found on separate continents, such as South America and Africa, strongly suggest that these regions were once connected and then slowly drifted apart, supporting the concept of continental drift and plate tectonics.

Landmasses in South America

In South America, the three main landmasses/landforms were mountains and highlands, river basins, and coastal plains. These 3 main geological landforms show that there were lots of plate movement and continental drift for these features to happen.

Landmasses in South America

Sam's Fun Fact

The the Paleozoic Era led to the introduction of the plants and animals that led to coal being made, the same coal that sees many uses today. Coal was only made during the Carboniferos period which occured during the later half of the Paleozoic Era.

Sam's Fun Fact

Mesosaurus

Mesosaurus were ancient reptiles that lived in South America during the Early Permian. They were skilled swimmers, spending most of their time in freshwaters. With their slender bodies and webbed feet, they effortlessly glided through the water. Mesosaurus feasted on small crustaceans, using their long, pointed teeth. Today, their fossils are instrumental in proving the theory of continental drift as they are found on separate continents, South America and Africa.

Diya's Fun Fact

Life in South America

A fun fact about South America during the Cenozoic era is the presence of colossal mammals known as Megatherium, enormous ground sloths that could reach the size of modern-day elephants. These gentle herbivores roamed the continent during this time, representing just one of the many fascinating and unique creatures that existed in South America millions of years ago.

Max's Fun Fact

Fun Fact

In the Pre-Cambrian era, continents formed and our modern atmosphere developed. The Pre-Cambrian era began with the birth of Earth and the formation of the moon. This era also included the first oceans.

Jayce's Fun Fact