Geology for ELR FSS3 is based on British Geological Survey (BGS) low-resolution data sampled at 100 metre intervals along the ELR. The geology presented should not be treated as accurate or complete. Data marked with Ⓤ is classed as undifferentiated by the BGS.
| Mileage | Material | Deposit | Bedrock |
|---|---|---|---|
| 35M 0301y to 37M 0385y | Sand and Gravel | River Terrace Deposits Ⓤ | Thames Group - Clay, Silt, Sand and Gravel |
| 37M 0385y to 37M 0715y | Silt | Brickearth | Thames Group - Clay, Silt, Sand and Gravel |
| 37M 0715y to 37M 1155y | Thames Group - Clay, Silt, Sand and Gravel | ||
| 37M 1155y to 39M 0986y | Sand and Gravel | River Terrace Deposits Ⓤ | Thames Group - Clay, Silt, Sand and Gravel |