Plate tectonics, predominantly buy custom essays online based mostly associated with the before strategy of continental drift proposed by Alfred Wegener is most likely definitely some of the most essential geological theories anytime created. This essay aims to buy custom essays online analysis the evolution of this concept as it has progressed from Wagener’s operate with the current buy custom essays online.
Continental drift plan
This idea was espoused by Alfred Wegener in 1912. In accordance to Torsvik & Cocks (2012), Wegener, a German meteorologist came up with the proposal that all the continents initially formed a single super-continent which he called Pangea, which was surrounded by a vast ocean called Panthalassa. This supercontinent later drifted apart forming the current day continents. Wegener’s centered his principle to your similarity between the coastlines on opposite sides for the Atlantic Ocean. He further expanded his thought in the premise that Permian flora as well as carboniferous fossils were found in South Africa, South America, India, Madagascar, Australia and Eastern Antarctica only and nowhere else leading him to hypothesize that these continents, now separated by oceans, were at one particular point joined together. Wegener hypothesized that the continents consist mainly of lighter rocks resting on heavier crustal materials and that their relative position is not fixed, but are slowly moving at the rate of approximately a yard per century. He therefore postulated a lateral movement of continents (Torsvik & Cocks, 2012) buy custom essays online.
A significant criticism of Wegener theory is that there was no plausible mechanism to explain the lateral movement of your continents. Further, it would have been expected that due to the lateral movements, there would have been physical evidence of massive thrust faults under the margins of continents, of which none existed further casting doubts on this theory.
Rolf, Coltice & Tackley (2012) affirms, and so do many researchers in this field that the fact that Wagener dependent much of his arguments for your apparently superficial similarity of symmetry from the coastlines, especially of South America and the West Coast of Africa further weakens his principle buy custom essays online. Such a match can only be identified at the continental shelf level hence basing it on coastlines is inherently flawed.
It appears that the primary reason why there was much resistance to this principle is given that much of Wegener’s work buy custom essays online was theoretical in that he dwelt so much on building theories out of his observation as opposed to being empirical which would have involved quantitative applications to support his arguments.
Contemporary plate tectonics idea.
Significant technological advances in the field of geological research especially during and after the Second World War yielded new data which led with the rejection of your vertical movements as proposed by Wegener. As Rolf et al. (2012) buy custom essays online succinctly puts it, three main discoveries provided the crucial stepping stones with the development belonging to the wider principle of Plate Tectonics, which was largely formulated between 1965 and 1968; http://www.buyessayshere.org/where-to-buy-essays Studies with the bathymetry of your ocean floor revealed massive ridges filled with magma from which it was believed the seafloor was spreading, mapping of the earth’s magnetic fields revealed irregular reversals in the magnetic fields polarity while studies in the paleomagnetic data from rocks of your same age from different continents showed different location of poles while that from rocks from different age from same location showed apparent reversal in polarity. The principle arose out of an attempt by geologists to explain these occurances.
According to Rolf et al. (2012), this theory postulates that the earth lithosphere is built up of plates that move relative to each other across the earth. These lithospheric plates consist of seven large and 18 smaller plates that diverge, converge and slip past 1 another along their boundaries. These plates can be either continental or oceanic or a combination of both and lie atop a layer of partly molten rock called the athenosphere.
The continental plates are mostly buy custom essays online done up of granite and are lighter while the oceanic plates are formed up of basalt and are denser. The continental plates hence float on top from the oceanic ones high up for your earth’s mantle. The interaction of these plates forms various types of plate boundaries; convergence boundaries are formed when plates collide/push against each other. Depending towards type of plates colliding, various features may be formed, for instance oceanic to oceanic plate convergence leads to formation of volcanic islands with the ocean, oceanic to continental convergence effects into volcanoes along the continental edges while continental to continental convergence leads to formation of mountain ridges like the Himalayas. Divergent boundaries are formed when plates move away from each other, this mainly happens at mid-ocean ridges leading with the formation of new crust at these boundaries. Lastly, transform boundaries are formed when plates slide earlier buy custom essays online each other, they are characterized by much seismic activity, an example is the San Andreas fault zone in California (Rolf et al., 2012).
Comparison of Wegener’s continental idea and the plate tectonics buy custom essays online theory bear many similarities. Wagener’s original notion had little objective content apart from the fit across the Atlantic coupled by the fact that the driving mechanisms behind his approach were unknown. In contrast, the current principle is backed by hard quantitative data and advanced technology. Nevertheless, Wegener’s approach played a key part buy custom essays online on the development of plate tectonics.
Current advances in technology including seabed mapping using advanced geophysical and sonar software utilizing 3-dimensional analytics may further advance the next revolution as considerably as earth sciences and plate tectonics is concerned.
Rolf, T., Coltice, N., & Tackley, P. J. (2012). Linking continental drift, plate tectonics and the thermal state for the Earth’s mantle. Earth and Planetary Science Letters, 351, 134-146.
Torsvik, T. H., & Cocks, L. R. M. (2012). From Wegener until now: the development of our understanding of Earth’s Phanerozoic evolution (Andre Dumont medallist lecture 2012). Geologica Belgica.