Geology for ELR HUL1 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 -066y to 2M 1705y | Clay, Silt and Sand | Alluvium | White Chalk Subgroup - Chalk |
| 2M 1705y to 3M 0715y | Clay, Silt and Sand | Alluvium | |
| 3M 0715y to 4M 0495y | Clay, Silt and Sand | Alluvium | White Chalk Subgroup - Chalk |
| 4M 0495y to 5M 0935y | Diamicton | Till | White Chalk Subgroup - Chalk |
| 5M 0935y to 5M 1595y | White Chalk Subgroup - Chalk | ||
| 5M 1595y to 6M 0495y | Diamicton | Till | Grey Chalk Subgroup - Chalk |
| 6M 0495y to 6M 0605y | Diamicton | Till | West Walton Formation, Ampthill Clay Formation and Kimmeridge Clay Formation Ⓤ - Mudstone |
| 6M 0605y to 7M 0495y | Diamicton | Till | |
| 7M 0495y to 8M 1705y | Diamicton | Till | West Walton Formation, Ampthill Clay Formation and Kimmeridge Clay Formation Ⓤ - Mudstone |
| 8M 1705y to 9M 0275y | Clay | Lacustrine Deposits Ⓤ | West Walton Formation, Ampthill Clay Formation and Kimmeridge Clay Formation Ⓤ - Mudstone |
| 9M 0275y to 9M 1595y | Clay | Lacustrine Deposits Ⓤ | Kellaways Formation and Oxford Clay Formation Ⓤ - Mudstone, Siltstone and Sandstone |
| 9M 1595y to 10M 0495y | Clay | Lacustrine Deposits Ⓤ | Great Oolite Group - Sandstone, Limestone and Argillaceous Rocks |
| 10M 0495y to 10M 1045y | Clay | Lacustrine Deposits Ⓤ | Inferior Oolite Group - Limestone, Sandstone, Siltstone and Mudstone |
| 10M 1045y to 12M 0385y | Clay, Silt and Sand | Alluvium | Lias Group - Mudstone, Siltstone, Limestone and Sandstone |
| 12M 0385y to 15M 0275y | Clay, Silt and Sand | Alluvium | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone |
| 15M 0275y to 22M 1485y | Clay | Lacustrine Deposits Ⓤ | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone |
| 22M 1485y to 25M 0055y | Clay | Lacustrine Deposits Ⓤ | Triassic Rocks Ⓤ - Sandstone and Conglomerate, Interbedded |
| 25M 0055y to 25M 1045y | Clay, Silt and Sand | Alluvium | Triassic Rocks Ⓤ - Sandstone and Conglomerate, Interbedded |
| 25M 1045y to 29M 0385y | Clay | Lacustrine Deposits Ⓤ | Triassic Rocks Ⓤ - Sandstone and Conglomerate, Interbedded |
| 29M 0385y to 30M 0886y | Clay, Silt and Sand | Alluvium | Triassic Rocks Ⓤ - Sandstone and Conglomerate, Interbedded |