The Weald region is primarily characterized by younger sedimentary bedrock that is visible at the surface, predominantly featuring mudstone, sandstone, and siltstone. These rocks are part of various geological formations that give the Weald its distinctive landscape.
The geological composition of the Weald, particularly its surface bedrock, largely consists of these sedimentary rock types, which were laid down millions of years ago.
Primary Sedimentary Rock Types
The surface geology of the Weald reveals a fascinating interplay of different sedimentary rock formations. These include:
- Mudstone: Fine-grained sedimentary rock, often associated with ancient marine or low-energy depositional environments.
- Sandstone: A clastic sedimentary rock composed mainly of sand-sized mineral particles or rock fragments, indicative of higher energy environments.
- Siltstone: A sedimentary rock intermediate in grain size between sandstone and mudstone.
Key Geological Formations and Their Composition
The specific rock types found in the Weald are organized into distinct geological groups and formations, each contributing to the diverse landscape of the area. The reference indicates that these visible surface rocks largely comprise:
| Geological Formation | Primary Rock Type(s) | Typical Location/Characteristics |
|---|---|---|
| Gault Clay | Mudstone | Predominantly found in the Low Weald |
| Weald Clay | Mudstone | A significant component of the Low Weald |
| Upper Greensand | Sandstone | Forms part of sequences alternating with mudstones |
| Lower Greensand | Sandstone | Also forms part of sequences alternating with mudstones |
| Wealden Group | Sandstone, Siltstone, Mudstone | Characterizes the High Weald, presenting mixed sequences |
The Gault Clay and Weald Clay are prominent mudstone formations, especially visible across the Low Weald. In contrast, the Upper Greensand and Lower Greensand primarily consist of sandstones. The High Weald is distinctive for its Wealden Group, which comprises a complex mix of sandstone, siltstone, and mudstone sequences.
