It does not matter if the earthquake happens during the day or night, what is more important is to protect yourself under a sturdy object such as a table or desk using the recommended method, DROP, COVER, and HOLD ON. However, if it is too dark, stay calm and protect yourself wherever you are, by ducking and protecting your head with your arms. If you are on your bed, put yourself in a fetal position, do not move and protect your head with a pillow or cushion. If you try to drop to the floor or run during an earthquake, it could raise the probability of injuries caused by fallen objects, and/or broken glass. Once the earthquake stops, use lanterns or flashlights to illuminate your way out the building. Avoid using fire (i.e., candles, matches). Keep in mind of the damage that may have occurred in your surroundings, including the possibility of gas leakage or spilled flammable liquids that could trigger a fire.

During an earthquake, you should stay away from everything made of glass or mirrors. The vibration produced by the seismic waves could shatter the glass causing the pieces to propel like projectiles. Move away from the windows and mirrors and look for a place where you can follow the DROP, COVER, and HOLD ON.

Earthquakes happen without previous warning and can be violent, without even a chance to run or move easily, nor avoiding falling down on the floor. The recommended action is to DROP, COVER, and HOLD ON as it could protect yourself. Duck and cover under a sturdy table or desk and hold on to it (even if it is moving) will increase the chance of survival and reduce injuries from falling or flying projectiles. The triangle of life proposes that during an earthquake it is safe to stand next to a strong object and not underneath it, since according to this method, when a building collapses, it crushes furniture, but creates a triangular void or space next to it, which is unaffected by falling debris. This concept relies on observations of imploded building collapses in Turkey, which is different from the damage caused by the propagation of seismic waves during an earthquake. It should be noted that Turkey's building standard codes are different from those used in countries such as the United States and Puerto Rico. It is also important to mention that Turkey has numerous active earthquake faults running through the country. The triangle of life method should not be the first choice of protection during an earthquake, as it has no scientifically proven support and relies on false assumptions such as the possibility of determining the direction in which the structure will collapse and thus identifying the safe space for protection, which is impossible to know before an earthquake occurs. The triangle of life also assumes that buildings will collapsed, that there will be enough time to move when finding the safe space next to a resistant object, assuming it did not moved during shaking. Recent studies of injuries and deaths resulted from earthquakes indicate that you will more likely be harmed by falling or thrown objects (televisions, lamps, glass, bookcases, etc.) than to die in a collapsed building. The "Drop, Cover, and Hold On" position is easy to understand, most people can do it, and chances are that wherever you are, you will be able to identify a sturdy object where to protect yourself under. For more information, go to http://www.earthquakecountry.org/dropcoverholdon.

The shaking of an earthquake can be so violent that it will not allow us to stand, much less run. When trying to run during the severe shaking by an earthquake we may easily fall, causing injuries from falling heavy objects around, glass or any object that shoots out. Evidence suggests that most injuries and deaths caused by earthquakes are by falling or flying objects and not by building collapses.

If the earthquake occurs while you are driving, if possible move to an area free of hazards (away from buildings, trees, poles, traffic lights, and electrical wiring), and stop until the shaking ends. Turn on the vehicle's emergency lights and tune in to a radio station that allows you to get updated information on the event. In most cases do not get out of the car as you will be safer inside. When the shaking stops, proceed with caution, move away from the coast, and avoid bridges or ramps as they may have unnoticed structural damage and may collapse. If you are near a bridge, overpass, or ramp, analyze the situation and determine if you need to move away from it or if it is safer to stay inside. Remember that evacuations should be on foot, as there may be debris in the way that may not allow you to pass.

If the shaking is too strong and does not allow you to move or take cover under a sturdy object, find an area free of hazardous objects such as glass windows, light fixtures, ceiling fans and unsecured shelving. Another option is to position yourself against an inside wall since exterior walls are more likely to collapse. Crouch down and cover your head with your arms until the shaking stops. If you have mobility problems or use a moving device (wheelchair, walker, cane) and cannot drop to the floor, move away from falling objects, apply the brakes on your wheel chair, and cover your head with your arms, pillow or cushion nearby, until the shaking stops. Avoid sheltering under the doorframe. Modern homes have structural elements, mostly aesthetic, that can weaken structures, and will not protect you from objects or glass expelled by the shaking.

No, Puerto Rico will not sink during a major earthquake because it is located on the Caribbean plate and is part of an emerging submarine mountain system founded on solid bedrock. This submarine mountain system is due to tectonic uplift by the subduction process generated by the North American Plate passing under the Caribbean Plate.

The easiest way to locate the epicenter of an earthquake is through triangulation. This method uses the distance data from three different seismic stations to determine where the earthquake occurred. On a map, circles are drawn around each seismic station. The radius of each circle is scaled to the estimated distance from the station to the earthquake. Earthquakes are composed of four types of seismic waves, Primary (P), Secondary (S), Love and Rayleigh. The arrival time of the P and S waves at each station is used to locate an earthquake. The difference, S-P, between the arrival times of both waves gives us the distance traveled by the seismic wave from the source to the station. The epicenter of the earthquake will be at the point where the 3 circles intersect.

The preliminary information of an earthquake is obtained through the first data coming from the seismic stations to a detection and analysis program. This program processes the seismic records that give us the location, depth, and magnitude of an earthquake, allowing us to inform the public, as soon as possible, of the event that has just occurred and even activate any alert if necessary. On the other hand, the updated information of the event is released after a geophysical analyst studies the traces or signal of the earthquake and integrates them to another program, which recalculates the data received from other seismic stations, obtaining a more accurate location, magnitude, and depth of the earthquake.

There is no way to determine if there will be a higher seismicity from one year to another, since there is no established pattern that confirms that the occurrence of earthquakes is constantly increasing. In Puerto Rico, as in other countries, the annual number of earthquakes could vary drastically from one year to another, depending on seismic activity. However, what has increased is the number of seismic stations and instrumentation and better earthquake detection and monitoring equipment. Currently, the seismic networks worldwide has modern equipment and automatic detection systems that allow us to register smaller earthquakes, even those not felt by people. There is also an increase in the means to access information such as television, radio, newspapers, and social networks, which keeps us informed about any seismic event occurring in our region, as well as in the rest of the world.

Aftershocks are tremors that occur after a major earthquake or main event in a seismic sequence. These earthquakes of smaller magnitudes and intensities occur in the same area of fault rupture or close to it. They are unpredictable and may cause the collapse of buildings already weakened or affected by the major event. They gradually decrease in magnitude and intensity, although the greater the magnitude of the main earthquake, the duration of the seismic sequence may continue for days, months or even years.

No, so far there is no correlation between weather conditions and earthquakes. Earthquakes are the result of the release of energy due to geological, physical, and chemical processes in the Earth's interior. They can occur in any climate and time of year, whether it is sunny or rainy weather, summer, or winter, temperate or tropical regions. Earthquakes originate miles deep in the Earth's crust, beyond the reach of atmospheric conditions, such as pressure, winds, and clouds, which do not interfere with the internal processes of the planet.

Many people think that the occurrence of many small earthquakes can prevent a large earthquake. However, the magnitude scale used to value the energy released by earthquakes is logarithmic, which means that each unit of magnitude is 30 times larger than the previous. Given this, for the energy of a major earthquake to be released, thousands or even millions of micro-earthquakes must occur on the same fault and at the same hypocenter, which is unlikely. Small earthquakes may release some stress, but not enough to prevent a large earthquake from occurring.

The effectiveness of communication methods after an earthquake will depend on what you have contemplated within your family emergency plan, work plan, etc. It is especially important to determine in advance a meeting place for emergencies and to identify an external (out-of-country) contact who will be responsible for keeping all family members, who are not together, informed during the emergency. It is unlikely that you will be able to make phone calls after an earthquake, due to congestion and the collapse of phone lines. If possible, send text messages, as they are more likely to get through than phone calls. Even if you do not see that the message has been sent, the moment you have some signal, the message will be sent. Text messages have a shorter bandwidth compared to voice messages or calls. If you see that you have a poor signal, opt to leave a message on your voicemail, indicating your status. With this, if your family member is unable to reach you, they will be able to listen to the message and know how you are doing. You can also choose to send messages to your family members through radio stations and social networks. It is important to remember that there is no 100% accurate or secure method of communication in emergencies, so the forms of contact will depend on the viable options you have at hand.

Although it is possible to monitor volcanic activity using seismic instrumentation, at present there is no scientific evidence that correlates the occurrence of earthquakes with volcanic eruptions. This means that a strong volcanic eruption will not generate an earthquake, nor will a strong earthquake cause a volcano to erupt. However, earthquakes of intermediate depth that occur in subduction zones favor volcanic activity.

You will be able to find tsunami evacuation maps for each coastal town, including Bayamón and Canóvanas (these two towns have large rivers that could increase their flow because of a tsunami arriving at the mouth of the river). To find these, you can go to http://redsismica.uprm.edu, click on the Terremotos and Tsunamis window located at the top right and choose Tsunami Program Portal. All maps are available for online access or download.

The assembly points indicated on the tsunami evacuation maps are determined by the municipality, Municipal Emergency Management, and the Puerto Rico Seismic Network. These assembly points are identified by a red circle, containing a letter and a number, which correspond to public places such as shopping center parking lots, parks, courts, among others. There are some criteria for the determination of these places, such as being accessible on foot, avoiding the use of bridges, minimizing evacuation time, among others. These meeting points are located outside the area delimited on the evacuation maps as tsunami evacuation zones. It is at these points where emergency management agencies and other first responders will arrive to offer services.

Tsunamis cause strong currents in coastal waters and flooding in low-lying coastal areas, endangering the lives of those who are there, destroying ecosystems and all kinds of stuff in their path. The generation of a tsunami will depend on the magnitude of the event that causes it (whether an earthquake, submarine landslide, submarine volcanic eruption, among others), its location, the bathymetry (depth of the seabed) and the elevations of the terrain (topography). In the case of tsunamis caused by earthquakes, their generation will also depend on the mechanism of fault rupture. On the other hand, the time of arrival of a tsunami to the coast will depend on the distance from where the disturbance was generated and the changes in depth of the seabed. Tsunami wave velocities are relative to bathymetry and decrease when they encounter shallow areas.

The eruption of a volcano can generate a tsunami only if it is a submarine volcano, i.e., underwater, and will depend on the depth at which it is located. However, a tsunami can also be triggered when a volcano near the coast erupts causing the collapse of one of its flanks generating the displacement of a large volume of water.

Conferences or information tables offered by the educational personal of the Puerto Rico Seismic Network are requested through the web page http://redsismica.uprm.edu. Once on the page, go to the "Earthquakes & Tsunamis" window on the upper right side and then select “Conference Request”. You will automatically be directed to the rules and instructions for requests. When you check the box accepting the conditions, a "Fill out online form" window will appear. Fill in all the blanks and submit the form. Once submitted, a Seismic Network employee will contact you within a reasonable amount of time to coordinate the activity. We have both face-to-face and remote talks, through digital platforms.