Geology for ELR BLI1 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 -086y to 0M 0275y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 0M 0275y to 0M 0385y | White Chalk Subgroup - Chalk | ||
| 0M 0385y to 0M 0605y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 0M 0605y to 0M 0935y | Lambeth Group - Clay, Silt, Sand and Gravel | ||
| 0M 0935y to 2M 1595y | White Chalk Subgroup - Chalk | ||
| 2M 1595y to 3M 0275y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 3M 0275y to 3M 1045y | White Chalk Subgroup - Chalk | ||
| 3M 1045y to 4M 0165y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 4M 0165y to 4M 0935y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | Lambeth Group - Clay, Silt, Sand and Gravel |
| 4M 0935y to 6M 0935y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 6M 0935y to 6M 1045y | Clay, Silt and Sand | Alluvium | White Chalk Subgroup - Chalk |
| 6M 1045y to 6M 1265y | Clay, Silt and Sand | Alluvium | |
| 6M 1265y to 6M 1485y | |||
| 6M 1485y to 7M 1595y | Clay, Silt and Sand | Alluvium | White Chalk Subgroup - Chalk |
| 7M 1595y to 8M 1265y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 8M 1265y to 9M 1155y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | Lambeth Group - Clay, Silt, Sand and Gravel |
| 9M 1155y to 9M 1705y | Clay, Silt and Sand | Alluvium | Lambeth Group - Clay, Silt, Sand and Gravel |
| 9M 1705y to 10M 0275y | Clay, Silt and Sand | Alluvium | Thames Group - Clay, Silt, Sand and Gravel |
| 10M 0275y to 10M 0825y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | Thames Group - Clay, Silt, Sand and Gravel |
| 10M 0825y to 11M 0825y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | Lambeth Group - Clay, Silt, Sand and Gravel |
| 11M 0825y to 15M 1045y | Sand and Gravel | Sand and Gravel of Uncertain Age and Origin | White Chalk Subgroup - Chalk |
| 15M 1045y to 16M 0825y | Silt | Brickearth | White Chalk Subgroup - Chalk |
| 16M 0825y to 19M 0880y | Clay, Silt and Sand | Alluvium | White Chalk Subgroup - Chalk |