geohazards in britian

• the somerset levels in 1607 flooded. Evidence from a layer of sand in mud deposits in five places:

  • South Gloucestershire
  • Cardiff 
  • Swansea 
  • Croyde bay 
  • Devon 
  • Bideford 
• somerset levels:

  Pebbles and broken shells were found - brought from the ocean. 
• Storegga slide

  Tsunami deposits of sand and rip up clasts of coastal deposits and microfossils were found under a peat line. Tsunami deposits found 9 meters above current sea level. 

   
• Storegga slide:

  • Expansion of methane hydrates 
  • Glacial sediment dropped off continental shelf
  • Isostatic rebound due to melting icecap 
• UK is a low to moderate earthquake hazard region. 
• Specific safety measures are not needed for most buildings, but are need for important structures like dams and nuclear facilities. 
• Major earthquake effects include fall of old structures and damage to anything else from the fall of material is secondary damage. 
• Largest recorded British earthquake was in june 1931 with a magnitude of 6.1, located in the north sea. 
• Low magnitude quakes occur every month but are rarely felt.