منابع مشابه
Surprises from the sea floor
Unknown planet: Around 72% of the Earth’s surface is covered by oceans, and much of that surface is still unchartered territory for science. (Graphic: SuperStock.) More than seventy percent of the surface of our planet is covered by oceans. 88 percent of their area is deeper than 1,000 metres and thus difficult to access for research. There are only a handful of research submersibles that can d...
متن کاملthe effect of taftan pozzolan on the compressive strength of concrete in the environmental conditions of oman sea (chabahar port)
cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...
Mineral resources and geo-engineering
Metals used in everyday life are produced from ores occurring in the Earth’s crust. Geological processes are known to concentrate minerals to form ores of economic value. Mineral processing engineers concentrate these ores by mechanical and physico-chemical methods while the extractive metallurgist extracts the metals by chemical means.
متن کاملExtending the sub-sea-floor biosphere.
Sub-sea-floor sediments may contain two-thirds of Earth's total prokaryotic biomass. However, this has its basis in data extrapolation from ~500-meter to 4-kilometer depths, whereas the deepest documented prokaryotes are from only 842 meters. Here, we provide evidence for low concentrations of living prokaryotic cells in the deepest (1626 meters below the sea floor), oldest (111 million years o...
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ژورنال
عنوان ژورنال: Journal of Geography (Chigaku Zasshi)
سال: 1967
ISSN: 0022-135X,1884-0884
DOI: 10.5026/jgeography.76.6_275