Geology for ELR SMS1 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 |
|---|---|---|---|
| 0M -088y to 0M 1705y | Thames Group - Clay, Silt, Sand and Gravel | ||
| 0M 1705y to 2M 0055y | Sand and Gravel | River Terrace Deposits Ⓤ | Thames Group - Clay, Silt, Sand and Gravel |
| 2M 0055y to 2M 0605y | Clay, Silt and Sand | Alluvium | Thames Group - Clay, Silt, Sand and Gravel |
| 2M 0605y to 3M 0137y | Thames Group - Clay, Silt, Sand and Gravel |