What happens to the seafloor as it moves away from the ridge?

What happens to the seafloor as it moves away from the ridge?

As oceanic crust moves away from the shallow mid-ocean ridges, it cools and sinks as it becomes more dense. This increases the volume of the ocean basin and decreases the sea level.

How the age of a rock changes as the distance from the mid ocean ridge increases?

With increasing distance from the axis of the ridge, the rocks become older, thicker, and cooler. They also have more sediments above them. Seafloor rocks are oldest near the edges of continents or deep-sea trenches. But even the oldest seafloor rocks are less than 180 million years old.

Why does the age of oceanic crust increases as the distance from the ocean ridge increases?

The new crust is pushed away from the Ocean Ridge in both directions as newer crust is formed. This is called sea floor spreading. The crust that makes up the sea floor starts to have time to accumulate a layer of sediments as it gets older and moves away from the Ocean Ridge.

What can you say about the thickness of the sediment far from the ridge?

As you move away from the ridge spreading center the sediments get progressively thicker (see section 4.5), increasing by approximately 100-200 m of sediment for every 1000 km distance from the ridge axis.

Why does the seafloor near the ridge be younger than those far from the ridge?

Why is the seafloor so young? It is due to the process of subduction; oceanic crust tends to get colder and denser with age as it spreads off the mid-ocean ridges. It gets so dense, that it sinks in the upper mantle (subduction).

How is the age of ocean sediments related to the distance from a mid-ocean ridge?

Seafloor sediment increases in thickness away from the mid-ocean ridge because the oceanic crust is older farther away from the ridge. More sediment will accumulate on the seafloor over time; therefore, the older the crust, the thicker the sediment deposits.

Why do the rocks ages increase as you get further from the center of the ridge?

As rocks crystallise from lava at the ridges, they literally record the magnetic field of the Earth at the time of their creation. The two parts of the oceanic plate are pulled apart, and magnetic stripes become older as they move away from the mid-ocean ridge.

Why does the oceanic lithosphere get thicker with distance away from the oceanic ridges quizlet?

Newly created oceanic lithosphere is hot and therefore less dense than cooler rocks of the deep-ocean basin. Why does the lithosphere thicken as it moves away from the ridge as a result of seafloor spreading? Because it is capped by large outpourings of basaltic lava or other crustal fragments.

What happens to the old oceanic crust?

The oldest oceanic crust is about 260 million years old. It is due to the process of subduction; oceanic crust tends to get colder and denser with age as it spreads off the mid-ocean ridges. It gets so dense, that it sinks in the upper mantle (subduction).

What happens to oceanic plates at convergent boundaries Brainpop ocean floor?

That’s when a dense ocean plate converges with a lighter continental plate. Dense sedimentary rock making up the Pacific seafloor is subducted, transformed into metamorphic rock through pressure and heat, and then recycled as igneous rock through volcanic eruptions.

What are the thickness of sea floor sediments?

This material comes from several different sources and is highly variable in composition, depending on proximity to a continent, water depth, ocean currents, biological activity, and climate. Sea-floor sediments (and sedimentary rocks) can range in thickness from a few millimetres to several tens of kilometres.

What causes sediment to thicken on the flanks of a ridge?

Sediment on ridge flanks commonly thicken with distance from the spreading axes, reflecting the increasing age of the volcanic seafloor. Complications to this simple picture occur where there is substantial sediment transport or varied dissolution of carbonate.

How does rapid deposition of sediment affect the seafloor?

Rapid deposition dramatically changes the sediment thickness, seabed slope gradient, and distribution of sediment; it has vital influence on the seafloor geomorphology and the physical and engineering features of sediment.

What kind of sediments are found on mid ocean ridges?

The sediments accumulating on and around mid-ocean ridges are mostly formed from the calcareous and siliceous tests of pelagic organisms.