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Terrestrial source theory: A simple, spherical splash-form Indochinite tektite The overwhelming consensus of Earth and planetary scientists is that tektites consist of terrestrial debris that was ejected during the formation of an impact crater. During the extreme conditions created by an hypervelocity meteorite impact, near-surface terrestrial sediments and rocks were either melted, vaporized, or some combination of these and ejected from an impact crater. After ejection from the impact crater, the material formed millimeter- to centimeter-sized bodies of molten material, which as they re-entered the atmosphere, rapidly cooled to form tektites that fell to Earth to create a layer of distal ejecta hundreds or thousands of kilometers away from the impact site.[ A moldavite tektite The terrestrial source for tektites is supported by well-documented evidence. The chemical and isotopic composition of tektites indicates that they are derived from the melting of silica-rich crustal and sedimentary rocks, which are not found on the Moon. In addition, some tektites contain relict mineral inclusions (quartz, zircon, rutile, chromite, and monazite) that are characteristic of terrestrial sediments and crustal and sedimentary source rocks. Also, three of the four tektite strewnfields have been linked by their age and chemical and isotopic composition to known impact craters. A number of different geochemical studies of tektites from the Australasian strewnfield concluded that these tektites consist of melted Jurassic sediments or sedimentary rocks that were weathered and deposited about 167 Ma ago. Their geochemistry suggests that the source of Australasian tektites is a single sedimentary formation with a narrow range of stratigraphic ages close to 170 Ma more or less. This effectively refutes multiple impact hypotheses. Although it is widely accepted that the formation of and widespread distribution of tektites requires the intense (superheated) melting of near-surface sediments and rocks at the impact site and the following high-velocity ejection of this material from the impact crater, the exact processes involved remain poorly understood. One possible mechanism for the formation of tektites is by the jetting of highly shocked and superheated melt during the initial contact/compression stage of impact crater formation. Alternatively, various mechanisms involving the dispersal of shock-melted material by an expanding vapor plume, which is created by a hypervelocity impact, have been used to explain the formation of tektites. Any mechanism by which tektites are created must explain chemical data that suggest that parent material from which tektites were created came from near-surface rocks and sediments at an impact site. In addition, the scarcity of known strewn fields relative to the number of identified Impact craters indicate that very special and rarely met circumstances are required in order for tektites to be created by a meteorite impact. These are significant in size compared with the slightly smaller options. Overall appearance is larger. Tumbled Tektite Meteorite khuya stone Black Size approx. 4.5cm x 3cm average size Origin: China Tektites, are pieces of natural glass. Several natural glass types are found on the Earth. By outward appearance some tektites resemble obsidian the commonest of the natural glasses. Microscopically, tektites resemble glass more than obsidian in that they are almost completely devoid of any mineral crystals in their composition. The tektite glass is homogeneous in nature with the elements it contains dissolved and mixed. Tektites have much less water in their composition than obsidians (often a thousand times less). Tektites are thought to come from: With severa schools of thought over the last hundred years, basically today it distils down to the Earth through the impact of a meteorite or comet.
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