The parish slopes gently from the northwest to southeast from a height of 250 feet to 50 feet at the southern boundary, Thorpe Beck.

The parish of Grindon lies in the geological area known as the Tees Lowlands. The underlying structure in this area is of Triassic deposits (195-225 million years old). During the last ice age a great thickness of ice was formed over the Tees Lowlands by glaciers flowing into the area from the Pennines, the Cheviots and Scandinavia. These glaciers contained large quantities of rock debris and boulders suspended in the ice. Indeed one such boulder can still be seen in the village of Sadberge, a few miles west of Grindon.

About 13,000 BC the climate warmed up and the ice melted. The rock debris was deposited as coarse boulders known as boulder clay with patches of gravel occurring.

Then a lake formed in the Tees Lowlands. This was fed by streams flowing from the residual glaciers in the west, which brought in finer sediments to be deposited on the lake floor.

Sea Level rose so that by 7,500 BC the British Isles were cut off from mainland Europe, the North Sea eroding the coastline to its present position by about 5,000 BC.

The deposits formed during this change are known as laminated clays made up of thin layers of fine sand and clays. These clays have a maximum depth of 10 metres (30 ft.) but thin out rapidly away from the River Tees petering out completely at between 17 and 25 metres (50-80 ft.) above sea level.

The deposits of sand and gravel often form workable deposits, which have frequently been exploited in the parish, particularly around the Thorpe Beck area.

The very fertile agricultural land of the parish is a result of this geology.

After the last Ice Age when the ice had retreated a covering of grasses and herbs spread in from the south and east followed by a variety of trees. First pine and birch followed by hazel, elm and oak with alder arriving by about 3000 BC. This heralded the first arrival of man.