REFERENCE: The Blue Planet An Introduction to Earth System Science. Brian J. Skinner and Barbara W. Murck (2011) Third Edition. John Wiley and Sons Inc.

Watch the YouTube video called

“How do tsunamis relate

to Earthquakes”

Tsunami (tsu=harbor and nami=wave) are often erroneously called tidal waves, but they have nothing to do with tides.They are initiated by sudden movement of the seafloor caused by

an earthquake, volcanic eruption, or underwater landslide.

Sumatra

Computer-simulated maps Satellite images of Sri Lanka

TAT = Tsunami Arrival Time

Magnitude 9.0Friday, March 11, 2011 at 02:46:23 PM at epicenter

Watch the YouTube video called

“Tsunami 101”

TSUNAMI IN PUERTO RICO

The 1918 San Fermín earthquake, also known as the

Puerto Rico earthquake of 1918, struck the island of

Puerto Rico at 10:14:42 local time on October 11. The

earthquake measured 7.1 on the moment magnitude scale

and IX (Violent) on the Mercalli intensity scale. The

mainshock epicenter occurred off the northwestern coast

of the island, somewhere along the Puerto Rico Trench.

The earthquake triggered a tsunami with waves measured

that swept the west coast of the island. The combined

effects of the earthquake and tsunami made it one of the

worst natural disasters that have struck the island. The

losses resulting from the disaster were approximately 76–

118 casualties[4] and $4–29 million in property damage.

TSUNAMI IN PUERTO RICO

Picture of damage caused by the 1918, Puerto Rico tsunami. This picture was taken in the

coastal area of "La Marina" in Mayagüez. The inscription on bottom leftmost part of the photo

reads "la imbacion del mar" or "the invasion of the sea". The tsunami ripped houses from their

foundations destroying some and others pulled out to sea when the tsunami retreated.

TSUNAMI IN PUERTO RICO

In this picture you can see the results of the effects of the forces contained in the

tsunami of 1918. This wooden house was torn from it's support columns and carried

out to the sea. Like in this example, the 1918 tsunami cause much damage and loss of

lives.

TSUNAMI IN PUERTO RICO

Approximately 45 people lost their lives because of the tsunami of 1918 in Puerto Rico. This

tsunami was caused by an earthquake of a magnitude of 7.5. Most structures at the time were

poorly constructed and did not survive the attack of the tsunami. Also their location close to

the sea or in flood able areas made them vulnerable.

TSUNAMI IN PUERTO RICO

This picture is also from the 1918 tsunami of Puerto Rico. Probably shot at the

Mayagüez city bay, it shows how the tsunami dragged a house out to sea. Also note

the tree that was unrooted and pulled to the bay. The tsunamis can will cause

destruction when they arrive as well as when they retreat.

TSUNAMI IN PUERTO RICO

In 1997 Professor Aurelio

Mercado, generated a

simulation that demonstrated

a possible scenario of the

1918 Puerto Rico Tsunami.

The results of this simulation

were compared to official

reports and witness accounts.

This confirmed the accuracy

of the simulation because the

simulation concurred almost

exactly to the what really

occurred in 1918.

Provided by Ruperto Chaparro