Geology for ELR BSD4 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 |
|---|---|---|---|
| 8M 0343y to 8M 1045y | Diamicton | Till | Pennine Lower Coal Measures Formation and South Wales Lower Coal Measures Formation Ⓤ |
| 8M 1045y to 8M 1209y | Clay, Silt and Sand | Alluvium | Pennine Lower Coal Measures Formation and South Wales Lower Coal Measures Formation Ⓤ |