System and Method for Warning of the Estimated Arrival Time and Expected Intensity in a Particular Area, Caused by a Seismic Movement

Abstract

The present invention relates to a method and system of warning of estimated time of arrival and expected intensity in a given area resulting from a seismic movement, which comprises a plurality of measurement elements or monitoring stations configuring a network of measurement elements, said method comprising the steps of: arranging the plurality of measurement elements in a specific area; communicating each of the measuring elements with at least one common point or control center; storing in each measuring element an identifier that will uniquely identify the same within the network of monitoring stations; transforming by means of the measuring element the measurement of the movement to a scalar or set of scalars representing the intensity of the movement; transmitting periodically and in real time the measurement and the unique identifier thereof to the control center for the duration of the movement; recording through the control center the individualized measurements from each of the monitoring stations; verifying through the control center if the received measurement corresponds to an actual earthquake or a mechanical noise; designating a destination point; determining the expected intensity and expected arrival time; automatically dispatching an earthquake early warning to the destination point.

Claims

1. A method of warning of estimated time of arrival and expected intensity in a given area resulting from a seismic movement, said method using a system comprising a plurality of measurement elements or monitoring stations configuring a network of measurement elements, CHARACTERIZED in that it comprises the steps of: a. arranging the plurality of measurement elements in a specific area or coverage area, which corresponds to the geographic region delimited by perimeter monitoring stations; b. communicating each of the measuring elements with at least one common point or control center; c. storing in each measuring element an identifier that will uniquely identify the same within the network of monitoring stations, having the ability to detect and measure the movement it experiences; d. transforming by means of the measuring element the measurement of the movement to a scalar or set of scalars representing the intensity of the movement; e. transmitting periodically and in real time the measurement and the unique identifier thereof to the control center, generating an individualized measurement, for the duration of the movement experienced by each measurement element until the measurement element does not experience any movement; f. recording through the control center the individualized measurements from each of the monitoring stations; g. verifying through the control center if the received measurement corresponds to an actual earthquake or a mechanical noise; h. designating a destination point to the geographic location where an earthquake early warning message is to be delivered, which is within the coverage area of the monitoring station network; i. determining the expected intensity and expected arrival time at the destination point by comparing the measurement recorded from a monitoring station with historical intensity and arrival time records at the control center from an initial station, which is part of a set of monitoring stations or initial swarm; j. in the event that a historical record coincides with the initial swarm of the new earthquake in progress, the geo-referenced location of the destination point to which the alert is to be sent shall be considered, searching the records for the monitoring station (1) closest to the location of the destination point of interest; and k. automatically dispatching an earthquake early warning to the destination point, where the warning signal will have as parameters the expected time of arrival and the expected intensity.

2. The method according to claim 1, CHARACTERIZED in that the control center corresponds to an automatic logical entity, which has data storage and processing capacity, and comprises at least one or more data servers that may be physically located in the same place or geographically distributed in different locations.

3. The method according to claim 1, CHARACTERIZED in that when recording each measurement, the control center also records the time said measurement is received, including the date, hour, minute, second, millisecond and microsecond of reception, thus defining a time stamp.

4. The method according to claim 1, CHARACTERIZED in that the monitoring stations are logically associated in sets of geographically close stations or swarms of stations.

5. The method according to claim 4, CHARACTERIZED in that a swarm of stations comprises N monitoring stations (1), wherein N>1.

6. The method according to claim 5, CHARACTERIZED in that each swarm of stations comprises a unique identifier, which is represented within the control center, where the swarm identifier and the identifiers of the monitoring stations grouped therein are recorded.

7. The method according to claim 6, CHARACTERIZED in that the same monitoring station may belong to more than one swarm.

8. The method according to claim 7, CHARACTERIZED in that in order to verify if the measurement corresponds to a real earthquake, T is defined as a predetermined and particular time window for each swarm of stations.

9. The method according to claim 8, CHARACTERIZED in that a telluric phenomenon is defined as real if M stations of a given swarm (wherein 1<M<=N) report similar measurements to the control center within the time window T.

10. The method according to claim 9, CHARACTERIZED in that the maximum distance at which two monitoring stations belonging to the same swarm x.sub.a and x.sub.b can be located from each other is such that the time elapsed since x.sub.a detects a real telluric movement and x.sub.b detects the same movement is less than T.

11. The method according to claim 9, CHARACTERIZED in that the minimum distance at which x.sub.a and x.sub.b may be located is such that the same mechanical noise of a non-telluric nature will be measured by x.sub.a at a value much higher (l.sub.a) or much lower than the measurement of the same movement made by x.sub.b (l.sub.b).

12. The method according to claim 1, CHARACTERIZED in that in the step of recording the measurement through the control center, the measurement is recorded in tables so as to determine the expected intensity and the estimated time of arrival.

13. A system of warning of estimated time of arrival and expected intensity in a given area resulting from a seismic movement, comprising a plurality of measuring elements or monitoring stations that form a network of measuring elements, CHARACTERIZED in that it further comprises at least one common point or control center that communicates with each of the measuring elements, and at least one destination point at the geographic location where it is desired to deliver an earthquake early warning message, which is within the coverage area of the network of monitoring stations.

14. The system according to claim 13, CHARACTERIZED in that the monitoring stations are logically associated in sets of geographically close stations or swarms of stations.

15. The system according to claim 14, CHARACTERIZED in that a swarm of stations comprises N monitoring stations (1), wherein N>1.

16. The system according to claim 15, CHARACTERIZED in that each swarm of stations comprises a unique identifier, which is represented within the control center, where the swarm identifier and the identifiers of the monitoring stations grouped therein are recorded.

17. The system according to claim 16, CHARACTERIZED in that the same monitoring station may belong to more than one swarm.

Description

DESCRIPTION OF THE FIGURES

[0021] FIG. 1 shows a diagram of the interaction between the monitoring stations and the control center according to one embodiment of the invention.

[0022] FIG. 2 shows a diagram of the network of monitoring stations distributed in a geographical area, according to one embodiment of the invention.

[0023] FIG. 3 shows a diagram of the distribution of swarms of stations distributed in a geographical area, according to one embodiment of the invention.

[0024] FIG. 4 shows a diagram of the distribution of swarms of intersecting stations distributed in a geographical area, according to one embodiment of the invention.

[0025] FIG. 5 shows a diagram of the detection of an actual earthquake, according to one embodiment of the invention.

[0026] FIG. 6 shows a diagram of the detection of a fake earthquake, according to one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0027] The system (100) of the present invention comprises a plurality of measuring elements or monitoring stations (1) configuring a network (10) of measuring elements (1), wherein each of the measuring elements (1) is communicated to at least one common point or control center (2), as symbolically depicted in FIG. 1.

[0028] The measurement elements (1) are arranged in a specific area or coverage area, which corresponds to the geographic region delimited by perimeter monitoring stations. Each measuring element (1) stores an identifier that will uniquely identify the same within the network (10) of monitoring stations (1) having the ability to detect and measure the movement it experiences. The measuring element (1) can transform the measurement of the movement to a scalar or set of scalars representing the intensity of the movement. The measurement and its unique identifier are then transmitted in real time to the control center, thus generating an individualized measurement. For the duration of the movement of each measuring element (1), individual measurements will continue to be transmitted periodically to the control center (2). If a measuring element (1) is no longer moving, it will no longer transmit any measurements to the control center (2).

[0029] In a preferred embodiment of the invention, the control center (2) corresponds to an automatic logical entity, which has data storage and processing capacity, and comprises at least one or more data servers that may be physically located in the same place or geographically distributed in different locations. The control center (2) receives and records the individualized measurements coming from each of the monitoring stations (1) of the system (100). By recording each measurement, the control center (2) also records the time at which it is received, including—to the extent possible, the date, hour, minute, second, millisecond, and microsecond of receipt. This record of time is called a time stamp. The time stamp shall be unique for each individualized measurement received from each monitoring station (1) of the system (100).

[0030] The system (100) of the present invention requires the presence of a large number of monitoring stations (1), geographically distributed in the region to be monitored (see FIG. 2). The higher the density of monitoring stations (1) in the system (100), the greater the effectiveness of functionality thereof.

[0031] For the operation of the system (100) monitoring stations (1) are required to be logically associated in sets of geographically close stations or swarms of stations (11) (See FIG. 3). A swarm of stations (11) comprises N monitoring stations (1), wherein N>1. Each swarm of stations (11) comprises a unique identifier, which is represented within the control center (2), where the swarm identifier and the identifiers of the monitoring stations grouped therein are recorded. As this is a logical association, it is possible that the same monitoring station (1) may belong to more than one swarm (11) as shown in FIG. 4, where it can be seen that station 168 is part of swarm D and swarm F, for example.

[0032] Furthermore, the control center (2) has the capability to record the time stamp for all individualized measurements coming from the monitoring stations (1) of the system (100). In order to detect as early as possible an earthquake, differentiating it from another source of mechanical noise, the system (100) performs the following operations:

[0033] T is defined as a predetermined and particular time window for each swarm of stations (11). The time window T will have certain restrictions that will be detailed hereinafter.

[0034] In order to conclude that a real telluric phenomenon is taking place, it will suffice that M stations of a given swarm (11) (being 1<M<=N) report similar measurements to the control center (2) within the time window T. M will be a function of the number of monitoring stations (1) of the respective swarm (11).

[0035] Being x.sub.i the swarm monitoring stations, where 0<i<=N.

[0036] Being x.sub.a and x.sub.b any two stations in the swarm so as to the maximum distance at which they can be located from each other is such that the time elapsed since x.sub.a detects a real telluric movement and x.sub.b detects the same movement is less than T.

[0037] Likewise, the minimum distance at which x.sub.a and x.sub.b may be located is such that the same mechanical noise of a non-telluric nature will be measured by x.sub.a at a value much higher (l.sub.a) or much lower than the measurement of the same movement made by x.sub.b (l.sub.b). In particular, if x.sub.a perceives a noise of non-telluric origin, x.sub.b will not perceive it and vice versa, as shown in FIGS. 5 and 6.

[0038] In order for the system (100) to determine the expected intensity and expected time of arrival, the destination point is designated as the geographic location where an earthquake early-warning message is to be delivered. In addition, the destination point shall be within the coverage area of the monitoring station network (10).

[0039] Arrival time is further defined as the measured time it takes for seismic waves to propagate from the point on the surface where they were detected by the network of monitoring stations (10) and the destination point during a historical seismic event. Expected arrival time is defined as the time it should take for seismic waves to propagate from the point on the surface where they were detected by the network of monitoring stations (10) and the destination point during a new seismic event that is in progress.

[0040] Expected intensity will be defined as the intensity that the destination point is expected to experience during an earthquake.

[0041] In the system (100) of the present invention, each time an earthquake occurs in the region of location of the network of monitoring stations (10), the individualized measurements are recorded in the control center (1) along with their respective time stamp.

[0042] It is known that the displacement velocity of telluric waves depends on the geology between the point of origin of the earthquake (hypocenter) and the point of destination (on the surface). Similarly, the change in seismic intensity between the point of origin of the earthquake measured on the surface, and the point of destination will vary depending on the geology of the land through which the telluric waves have to pass, and depending on the energy released by the seismic event.

[0043] In the system (100) of the present invention it is possible to record the historical behavior of seismic wave propagation through the network of monitoring stations (10).

[0044] Considering that the network of monitoring stations (10) involves a suffice density, it is possible to construct the following tables that will be used to determine both the estimated time of arrival and the expected intensity.

[0045] Tables of Historical Intensities by Origin

[0046] Each time an earthquake is recorded, it is followed by a series of tremors known as aftershocks, which usually take place in a volumetric zone close to the hypocenter. This feature of large earthquakes—as well as the fact that in most cases earthquakes at a given geographic point will occur at approximately the same depth, will be exploited in favor of the warning method of the present invention.

[0047] In either case, each time an earthquake occurs, the monitoring station (1) that first detected the event will be known, which will be referred to as the initial station.

[0048] In particular, the swarm to which the initial station belongs will also be known, and will be referred to as the initial swarm. This will allow the creation of a table called as table of historical intensities by origin, which will allow the initial swarm to be related to the rest of the monitoring stations in the network, showing how the intensity and arrival time behaved. For example, tables 1 and 2 are shown. These two tables correspond to a series of tables representing all swarms (11) of stations (1) that were once initial swarms for some historical earthquake. Tables 1 and 2 are intended to represent that there will not be a historical record of all possible maximum intensities; however, in order to supplement the historical information, the effects of the missing maximum intensities for each origin could be interpolated or extrapolated, as the case may be, by means of some relevant function. Thus, the tables would consist of historical information supplemented with inferred data. The proposed system (100) and method can be improved with each new seismic event that occurs, having more historical information that allows adjusting those data that have been initially inferred.

[0049] Tables of Historical Intensities by Origin

TABLE-US-00001 Swarm B Historical intensity (MM) Monitoring station Arrival time (s) 8 6 5 4 3 Station 1 22 6 3 2 1 0 Station 2 16 7 5 4 0 0 Station 3 11 7 5 5 2 0 Station 4 0 8 6 5 4 3 Station 5 0 8 6 4 4 3 Station 6 15 7 5 3 3 2 Station 7 21 7 4 2 2 0 Station 8 22 6 3 0 0 0 Station 9 21 6 3 0 0 0 Station 10 31 5 0 0 0 0 Station 11 32 4 0 0 0 0 Station 12 47 3 0 0 0 0

TABLE-US-00002 Swarm J Historical intensity (MM) Monitoring station Arrival time (s) 9 7 5 Station 1 59 5 0 0 Station 2 40 5 0 0 Station 3 32 6 2 0 Station 4 31 6 4 0 Station 5 25 6 5 2 Station 6 20 7 5 3 Station 7 14 8 6 4 Station 8 12 9 7 4 Station 9 0 9 7 5 Station 10 0 9 7 5 Station 11 10 9 6 4 Station 12 12 8 5 3

[0050] The reason why only one column appears with the arrival time for each table is due to the propagation velocity of the seismic waves; therefore, the respective arrival time does not depend on the earthquake intensity.

[0051] Hence, every time a new earthquake occurs, the control center (2) will have to review its historical tables of intensities by origin. In the event that a table coincides with the initial swarm of the new earthquake in progress, the geo-referenced location of the destination point to which the alert is to be sent shall be considered, searching in said table the monitoring station (1) closest to the location of the destination point of interest. This cross-checking of data allows the control center (2) to automatically dispatch an earthquake early warning to the destination point, where the warning signal will have as parameters the expected time of arrival and the expected intensity.