"
Hamilton explains that while Continental Lithosphere is as much as 93 miles thick, the "Oceanic Lithosphere" is much thinner - up to perhaps six miles. Indeed, the oceanic crust makes up only 0.099% of earth's mass, according to Hamilton. Oceanic lithosphere is a product of the volcanic magma that pushes up to force tectonic plates aside. As new oceanic lithosphere is actually formed the heat that comes up with the magma "escapes the interior as this new lithosphere emerges from below" in the Red Sea and elsewhere where there are tectonic plates spreading.
As the lithosphere cools, it contracts and then "moves away from the ridge, traveling across the seafloor to subduction zones." This process is technically called "seafloor spreading." After the lithosphere has been on the Red Sea floor for a while, it thickens up, Hamilton writes, and as it becomes even denser than the mantle just below it, it sinks into the earth (called "subduction") at a "steep angle" which cools the interior below the tectonic plates.
As a side note to undersea spreading, Hamilton mentions that as a rule all continents drift laterally along the "...convecting system of the mantle away from hot mantle zones toward cooler ones"; this is called continental drift, and "most" continents are either moving toward cooler parts of the mantle of earth. Or they are sitting on a cooler part of the earth's mantle. Africa is the one exception to this geologic rule, Hamilton continues. Africa was at one time - several hundred million years ago - the "core" of Pangaea, the "supercontinent" that broke into the continents that make up the earth's main land masses today.)
Meantime, the New York Times reported in 1987 that information about the spreading of sea floors is easier to come by thanks to "remote-controlled instruments and a new generation of manned deep-diving vessels." These technological developments have helped - and will continue to help - scientists learn more about how oceans and continents are being split apart. The training for proper use of these technologies was given in the late 1980s to 3,500 scientists from 78 countries; during the training session it was projected by Rodey Batiza of Northwestern University that they may be "a million volcanic mountains on the floor of the Pacific Ocean," most directly related to tectonic plate movement and magma surging upwards.
Among the 3,500 scientists there was "wide agreement" that the energy that is pushing the tectonic plates apart under seas and oceans comes "chiefly from the heat of radioactive decay inside the earth." Moreover, two scientists (Dr. R.W. Girdler of the University of Newcastle-upon-Tyne in England and P.R.K. Simpson) stated that magnetic instruments have indicated that the Africa plate and Arabian plate are "an unusual case" in which a "sea-floor spreading penetrates deep into a continent" (more on this topic will be discussed later in the paper).
This article was written, and the conference was held, well before the confirmation of the split under the Red Sea; still, at the time of the conference the scientists reported that the rift under the Red Sea was spreading at the rate of "about one inch per year"; and the rifting continues north through the gulf of Aqaba into the Dead Sea rift valley; that spreading rate is only have of the rate under the Red Sea.
RED SEAFLOOR RUPTURING: RECENT RESEARCH
The National Sciences Foundation (NSF) (Fall, 2006) MARGINS Newsletter No. 17, reports on the rupturing continental lithosphere dynamics in the northern and central Red Sea. In the narrative references are made to a recent an initiative launched to better understand "continental expansion" and how that transcends into ocean spreading. In this report - with data gathered from scientists from Massachusetts Institute of Technology, Penn State University and the University of Kansas - scientists explain that before studying the rupturing issues beneath the seafloor of the Red Sea, logistical and political issues had to be ironed out. The scientific collaborations that had been planned for this project - with scientists from Egypt, Sudan, Jordan, Eritera, and Saudi Arabia, were not workable.
Unfortunately due to the current security situation and political climate in the Middle East, the NSF...could not longer consider U.S.-led marine geophysical experiments in the Red Sea at this time" (Reilinger, 2006). This political dilemma sheds light on the fact that there is a great deal of tension, first, between the Muslim states in the Middle East and the West in general, and secondly, the United States is engaged in a controversial war in Iraq - and...
This entity follows the California Clean Air Act and the Federal Clean Air Act so that it is responsible for air monitoring, permitting, enforcement, long-range air quality planning, regulatory development, and education and public information activities with regard to air pollution. A more recent concern has developed as the first cruise ship to enter Monterey Bay since 1966 caused environmental groups to demand increased protection for marine sanctuaries and to
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