Answer:
The oldest rocks of the oceanic crust are found in deep ocean trenches far away from active mid-ocean ridges.
Explanation:
Beginning in the late 1940s, oceanic expeditions continued to map the Atlantic ocean floor using new equipment and collecting thousands of rock samples. These works made it possible to map a gigantic system of submarine mountain ranges, called meso-ocean ridges. By perfecting the method of dating rocks, scientists have been able to determine the true age of seabed rocks. They found that the closer to the mid-ocean ridge the rocks were much younger than imagined, while rocks close to the continents were increasingly older, thus corroborating the Continental Drift.
The correct answer is letter B. increase deposition of sediments upstream. The negative effect of using too much water for the irrigation of crops is that it wash out sediments and these sediments are brought down the water streams.
Consolidating name geology