4 intensity Flashcards
Perceptible to people under favorable circumstances. Delicately balanced objects are disturbed slightly. Still Water in containers oscillates slowly.
I Scarcely Perceptible
Felt by few individuals at rest indoors. Hanging objects Swing slightly. Still Water in containers oscillates noticeably.
II Slightly Felt
Felt by many people indoors especially in upper floors of Buildings. Vibration is felt like one passing of a light truck.
Dizziness and nausea are experienced by some people. Hanging objects swing moderately. Still water in containers Oscillates moderately.
III Weak
Felt generally by people indoors and by some people Outdoors. Light sleepers are awakened. Vibration is felt
Like a passing of heavy truck. Hanging objects swing Considerably. Dinner, plates, glasses, windows and doors Rattle. Floors and walls of wood framed buildings creak. Standing motor cars may rock slightly. Liquids in containers Are slightly disturbed. Water in containers oscillate Strongly. Rumbling sound may sometimes be heard
IV Moderately Strong
Generally felt by most people indoors and outdoors. Many Sleeping people are awakened. Some are frightened, some run Outdoors. Strong shaking and rocking felt throughout building.
Hanging objects swing violently. Dining utensils clatter And clink; some are broken. Small, light and unstable Objects may fall or overturn. Liquids spill from filled open Containers. Standing vehicles rock noticeably. Shaking of Leaves and twigs of trees are noticeable.
V Strong
Many people are frightened; many run outdoors.
Some people lose their balance. Motorists feel like driving
in flat tires. Heavy objects or furniture move or may be shifted.
Small church bells may ring. Wall plaster may crack. Very old
or poorly built houses and man-made structures are slightly Damaged though well-built structures are not affected. Limited rock falls and rolling boulders occur in hilly
to mountainous areas and escarpments. Trees are noticeably Shaken.
VI Very Strong
Most people are frightened and run outdoors. People find it Difficult to stand in upper floors. Heavy objects and furniture Overturn or topple. Big church bells may ring. Old or Poorly-built structures suffer considerably damage.
Some well-built structures are slightly damaged. Some cracks may appear on dikes, fish ponds, road surface, or concrete
Hollow block walls. Limited liquefaction, lateral spreading And landslides are observed. Trees are shaken strongly.
(Liquefaction is a process by which loose saturated
Sand lose strength during an earthquake and behave like liquid).
VII Destructive
People are panicky. People find it difficult to stand even Outdoors. Many well-built buildings are considerably
Damaged. Concrete dikes and foundation of bridges are Destroyed by ground settling or toppling. Railway tracks
Are bent or broken. Tombstones may be displaced, twisted
Or overturned. Utility posts, towers and monuments mat tilt
Or topple. Water and sewer pipes may be bent, twisted or broken.
Liquefaction and lateral spreading cause man- made structure To sink, tilt or topple. Numerous landslides and rock falls Occur in mountainous and hilly areas. Boulders are thrown Out from their positions particularly near the epicenter. Fissures and faults rapture may be observed. Trees are Violently shaken. Water splash or stop over dikes or banks
Of rivers.
VIII Very Destructive
