Video instructions and help with filling out and completing Why Form 2220 Circular

Instructions and Help about Why Form 2220 Circular

There's no more earth hypothesis proposes that Earth's surface became almost entirely frozen during the cryogenian period from about 850 to 630 million years ago in 1964 brian Harlan proposed that a global scale glaciation had occurred before the Cambrian period he based his conclusion on paleomagnetic data showing that glaciers had existed the tropical latitudes the petrified glacial sediments on opposite sides of the South Atlantic Ocean provided early evidence for continental drift and they also provide the support for the Precambrian snowball earth glaciation hypothesis in 1969 mikail bedico a russian climatologist published an energy balance model to calculate the effect of ice cover on global climate boudicca's model predicted that if the ice sheets advanced far enough out of the polar regions they increased reflectiveness of the ice led to further cooling until the entire earth was covered with ice the physical evidence in the computational model firmly established the snowball earth hypothesis the world was very different at the time of the snowball earth the supercontinent Rodinia formed about 1,100 million years ago it was the dominant landmass for about 350 million years geologist generally agree that the east coast of present North America go Lauren Chia was adjacent to Western South America which then consisted of the Rio de la Plata in Amazonia cratons the west coast of North America lay next to what is today Australia in Antarctica rodinia broke apart during the cryogenian period from about 750 to 600 million years ago to form the pan-african mountains in a new supercontinent called Pangea the cryogenian period from 850 to 630 million years ago included the breakup of Rodinia the snowball earth freezing event caused the mass extinction of 70% of the dominant algae like sea plants 650 million years ago the cryogenic was followed by the deeakron period during which the supercontinent pannotia was formed in the first multicellular soft-bodied organisms appeared it is thought that snowball earth filled out as a result of volcanic activity which added carbon dioxide to the atmosphere and increase the greenhouse effect but the cost of the glaciation is not known several ideas have been proposed such as the decrease of carbon dioxide in the atmosphere by the formation of carbonates and by the photosynthetic activity of cyanobacteria also the runaway cooling effect of increased ice cover on the earth has been considered because ice reflects 85% of the sunlight whereas open ocean reflects less than 10% of the sunlight other possible causes for the snowball earth could have been the increased tectonic activity from the breakup of rodinia or the catastrophic effect of an extraterrestrial impact the idea of an extraterrestrial impact as the cause of the snowball earth has not received much attention the a year mountains in Asia have some interesting circular geological features that could have been caused by impacts of a cluster of comet fragments in 1974 rule of Roche Wyler determined that the a year mountains have an oldest date of formation of 660 million years which is approximately the time of the cryo geniune extinction the overlapping rings of their mountains can be explained that the result of impact by a dense cluster of meteorites rather than as the result of antigenic geological processes but the site has substantial evidence of volcanic lava that could have been triggered by the powerful impacts of the cluster of comet fragments the Iron Mountain's have been described as granite institutions of Precambrian origin by several authors including Ron Schwimmer in 1994 Moreau and three co-authors claimed that the ring structures in the area mountains are a more recent origin in attribute their formation to a major magnetic event in the Paleozoic era how is it possible that mountains with elevations from 900 to 1700 meters above sea level could be the site of an extraterrestrial impact one possibility is that the impacts were concentrated in a small area and there were vigorous enough to crack the Earth's crust and trigger volcanic and tectonic activity that raised the landscape this image highlights the circular structures of the iron mountains surrounded by fields of lava that created the mountain range notice the distribution of the circular areas from the top to the bottom which is reminiscent of the trail of impacts left on Jupiter's atmosphere by pieces of the shoemaker-levy comet in 1994 this is a detailed view of the major cluster of overlapping circular structures high-resolution images can be obtained from satellite images of Google Maps starting at latitude 18.8 and longitude 8.8 the largest of the circular areas labeled the circle five has a diameter of 60 kilometers the northwest edge of circle five is a very prominent circular arc in the southeast edge is faint but distinct the western outline of circle five has been degraded by erosion but some traces of the circle are still visible the combined energy of the impacts that created these circles is equivalent to two thousand two hundred and twenty megatons of TNT which is comparable to the energy from the impact that ended the era of the dinosaurs in addition the disintegration of a comet I said entered the atmosphere would have released a large amount of gaseous components that would have destroyed the ozone layer and altered the atmospheric composition of the earth we will now take a look in more detail at the intersection of circles three and five this image shows the overlaps of circles three and five the mechanism for the formation of overlapping rings would be similar to the intersection of circular ripples created from multiple objects dropped in quick succession into water the interaction of the circular waves provides evidence that the events that form the overlapping circles happen while the surface was molten the center of circle three is just inside the edge of circle five and a splash zone outside of circle five is highlighted the impact for circle three happened after the rim of circle