Answer:
Explanation:pon studying the Gubbio samples, Luis Alvarez wanted to know how long the foram extinction lasted before the species began to re-establish itself. He suggested the samples be handed over for analysis to another pair of Berkeley Lab scientists, nuclear chemists Frank Asaro and Helen Michel, who had developed a technique, called neutron activation analysis, that enabled precise measurements of very low concentrations of elements. Luis believed that neutron activation analysis would help determine how long it took for the clay layer to form. To the surprise of everyone involved, the measurements by Asaro and Michel showed that the clay layer was about 600 times richer in iridium than the surrounding limestone. Iridium, a silvery-white metal related to platinum, is virtually absent from the Earth’s crust, but high concentrations are common in extraterrestrial objects, such as asteroids.
The plot thickened when this same “iridium anomaly” was subsequently discovered in clay layers at locations in Denmark and New Zealand, and later dozens of other sites around the world where the geological record of the Cretaceous-Tertiary boundaries are also complete. These iridium-spiked layers of clay also contained an abundance of soot. Comparisons of ratios between iridium and several other key elements in the clay layers indicated that the widely scattered iridium anomalies all came from the same source – one that was not of this earth.
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The terrestrial region and the celestial region
Imperialism is a relationship between countries that is based on ideas of superiority and applying domination practices, which involve the extension of authority and control of one State or people over another. It can also be a political doctrine that justifies the domination of one people or State over others; usually through different types of colonization (settlement, economic exploitation, strategic military presence) or cultural subordination (acculturation).
There were several causes of Imperialism. The crisis of 1873 caused the decline in prices, products of each country prohibiting the entry of foreign goods or taxing them. This led to the need to find new markets that were not controlled by this system. On the other hand, European capitalist powers such as England, the Netherlands and France needed to give out their capital surplus and did so by investing it in countries of other continents, establishing loans, implementing railroads, installing ports, etc. In addition, these countries needed to look for raw materials for their industries, since they began to run out or to be scarce in Europe. The Second Industrial Revolution, on the other hand, needed new raw materials that Europe did not have, such as silver, oil, rubber, gold, copper, etc. The economic causes were the result of the expansion of industrial capital and were forced to seek new territories where they could invest the excess capital accumulated, these capitals found a productive output in the form of credits granted to the minority of indigenous people.
