I am really struggling with this. Could anyone good at Earth science help me wit

Question

I am really struggling with this. Could anyone good at Earth science help me with detail essay, please?

This is the composition of a sediment core from one place in the deep ocean. It was recovered in a water depth of 4000 m. How can this layering be explained? What are the conditions under which each of these layers would be expected to have been formed? Recognizing that this location is on a moving plate, what does this tell you about the path (geologic history) of this location of the sea floor at this location?

Explanation / Answer

Pelagic sediments are sediments which are fine grained and they accumulate as settlings on the ocean floor, the major type of pelagic sediments are red clays, calcareous and siliceous ooze and sometimes a very tiny/trace amounts of meteoric dust and volcanic ash can be found.

                Pelagic sediments composition are controlled by three major factors, which are distance from the land which will affect dilution by sediments derived from land (terrigenous), water depth which show affect on preservation of calcareous and siliceous particles as they move down to the ocean floor and the last one is fertility of the oceans producing large amount of biogenic particles on water surfaces.

OOZES

                Oozes include many organisms like pteropod, coccoliths, radiolarian, diatoms, foraminifera, globigerina etc. They have the composition of silica and calcium too, settling slowly in the oceans may take few centimeters for thousands of year.

                Calcium ooze is one of the type covering 48% of the ocean floor around the world. Generally these calcium oozes accumulate on the ocean floor if the oceans are above the calcium compensation depth which may vary from 4300-5000(approx.) all over the world, below this, there will be the dissolution of calcium ooze as the oxygen levels will be decreasing, results in no accumulation after the calcium compensation depth. Calcareous ooze accumulation for thousand years will be 5 cm thickness.

                Siliceous ooze can accumulate on the surface floor of oceans below the carbonate compensation depth. They accumulate very slowly than calcareous ooze, may be for thousand years only 0.2/1 cm thickness will accumulate.

RED AND BROWN CLAYS

                                Red clays are also called pelagic or brown clays, generally accumulate in the area which are deeper in the oceans, these clays comparatively, they accumulate very very slowly than oozes on the ocean surface. These red clays are the sediments consisting of clay minerals, aeolian quartz and volcanic ash. The colour of clays are because of organic carbon absence due to which manganese and iron remain in oxidized state, so the clays remain brown , as they are deep buried changes to red clays. These Red clays accumulate on ocean surface where there is a little planktonic activity. These clays have been transported to deep oceans in suspension which be either by air flowing above the oceans or on the surface waters, these ocean and wind currents transporting these sediments through suspension few thousands of kilometers away from the oceans for so many thousands of year.

IN THE GIVEN PICTURE/SCENARIO

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