Deeply Weathered Rock

You would think that when the bedrock was buried 30m below theground level, it should be well protected and in nice form. 
This photo tells you a different story. The Shale bedrock at 28m to 33m is almost disintegrated especially towards the deeper depth. 
Previous blog had shown you why and how water permeated into the rock.
Give these rocks another thousands of years, they will turn into soils, clay/silt with some sand.

Oh, what are those crystallised whitish pieces of rocks embedded in the dark grey Shale rock at 32.5m depth?

These rocks were not from above, i.e. not deposited soils from Earth weathering processes. They were from deep beneath the earth, 10-30 kilometres down from magma layer, who tried to escape to the surface through cracks and small vents, probably million years ago, but lost their steam before reaching the surface and solidified to form quartz seam. They are now weathered into smaller quartz pieces. Quartz is the second most abundant minerals on Earth.