See detailed information for ELR THO
⚠️ Geology shown below is based on British Geological Survey (BGS) low-resolution data sampled at 100 metre intervals along the ELR. The geology relative to the mileages should not be treated as accurate or complete. Data marked with Ⓤ is classed as undifferentiated by the BGS.
| Mileage | Material | Deposit | Bedrock |
|---|---|---|---|
| 0M -216y to 1M 1705y | South Wales Upper Coal Measures Formation - Mudstone, Siltstone, Sandstone, Coal, Ironstone and Ferricrete | ||
| 1M 1705y to 2M 0385y | Clay, Silt and Sand | Alluvium | South Wales Upper Coal Measures Formation - Mudstone, Siltstone, Sandstone, Coal, Ironstone and Ferricrete |
| 2M 0385y to 3M 0605y | Clay, Silt and Sand | Alluvium | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone |
| 3M 0605y to 3M 1045y | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone | ||
| 3M 1045y to 4M 0165y | Clay, Silt and Sand | Alluvium | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone |
| 4M 0165y to 4M 1485y | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone | ||
| 4M 1485y to 4M 1705y | Dinantian Rocks Ⓤ - Limestone with Subordinate Sandstone and Argillaceous Rocks | ||
| 4M 1705y to 5M 0605y | Triassic Rocks Ⓤ - Mudstone, Siltstone and Sandstone | ||
| 5M 0605y to 6M 0165y | Dinantian Rocks Ⓤ - Limestone with Subordinate Sandstone and Argillaceous Rocks | ||
| 6M 0165y to 6M 0495y | Lower Devonian Rocks Ⓤ - Sandstone and Conglomerate, Interbedded | ||
| 6M 0495y to 6M 0616y | Triassic Rocks Ⓤ - Sandstone and Conglomerate, Interbedded |