I am an igneous rock black or grey in colour I make up most of the ocean floor
Answers
Answer:
The Earth was formed about 4.6 billion years ago. The planet was so hot that the entire Earth was molten or liquid. As the Earth cooled, the lightest materials floated to the top and the heaviest materials sank to the center. The outer part of the Earth, the crust, consists of the lightest rock.

The lightest rocks form the continents, which are made mostly of the rock granite. Most of the granite on the continents has, over millions of years, been broken down, transported, and deposited into sedimentary rock. These layers of sedimentary rock vary from 8-9 miles thick to nothing in some areas like the Canadian Shield of North America. The Canadian Shield has huge outcroppings of granite right on the surface. Under the thick layers of sedimentary rock lies the denser granite.
The granitic continents ride on a much denser rock called basalt. These basalts form the bottom of our continents and the bottoms of our great oceans. This layer of rock extends down to 40 miles from the surface of the earth.
Answer:
Basaltic
Explanation:
- Most to the oceanic floors are made by the spreading of the lavas and the magmas on either side of the mid oceanic ridges and these ridges tend to deposit the lavas on the north and the southern sides of the floor and hence leads to the formation of the newer oceanic floor and the rocks that are younger in nature tend to be found closer to the ridges and the rocks that are older far away.
- These rocks have a fiery content and are high on the silica contents and their crystals are denser and these rocks re dark-colored, thin and heavy and are quite hard and make up most of the seafloor, as evident by the sea floor spreading.