In the process of cooling and condensation, the crust on the earth's surface is constantly impacted and squeezed by the violent movement inside the earth, so it becomes uneven and sometimes crushed, forming earthquakes and volcanic eruptions, spewing magma and hot gas.
For a long time, the water vapor in the sky coexisted with the atmosphere, with dense clouds and dark days. With the gradual cooling of the earth's crust, the temperature of the atmosphere is also slowly decreasing. Water vapor takes dust and volcanic ash as condensation nuclei and becomes water droplets, which accumulate more and more. Due to uneven cooling and strong air convection, lightning storms and turbidity currents have formed, and it has been raining harder and harder for hundreds of years. Surging floods, through thousands of rivers and valleys, converge into a huge water body, which is the primitive ocean.
In the primitive ocean, seawater is not salty, but acidic and anoxic. Water is constantly evaporating, repeatedly forming clouds to cause rain, falling back to the ground, dissolving salt in rocks on land and seabed, and continuously collecting it into seawater. After hundreds of millions of years of accumulation and integration, it has become a generally uniform salt water.
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Application of marine resources:
1, medical resources
Some drug researchers are conducting experiments to extract toxic compounds from algae and tiny marine life as an effective means to treat some diseases. Preliminary experiments show that toxic substances extracted from sponges can inhibit the development of cancer cells.
Medical experts attach great importance to the development and utilization of coral when considering taking medicine from the ocean. Experiments show that the toxic substances extracted from coral reefs, like those extracted from some spongy creatures, also have the effect of inhibiting the development of cancer cells; Other substances extracted from coral reefs can reduce inflammation of arthritis and asthma.
There is a kind of coral from Hawaii, which is very toxic and can be used to make specific drugs for leukemia, hypertension and some cancers. Soft coral purified from Nanhai, China, has the functions of lowering blood pressure, resisting arrhythmia and relieving spasm.
2. Mineral resources
Oil and gas fields-With the modernization of human economy and life, the demand for oil is increasing. At present, oil occupies the first place in energy. However, because some large oil fields on land are relatively easy to exploit, some have been exhausted and some are on the verge of exhaustion.
In the past two or three decades, many countries in the world have been vigorously developing offshore oil industry. The exploration results show that the world oil resources reserves are 654.38+000 billion tons, and the recoverable amount is about 300 billion tons, of which the seabed reserves are 654.38+03 billion tons.
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