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(12> Ulllted States Patent (16) Patent N63 US 6,373,396 B2

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(12> Ulllted States Patent (16) Patent N63 US 6,373,396 B2 US006373396B2 (12> Ulllted States Patent (16) Patent N63 US 6,373,396 B2 Zamfes (45) Date of Patent: Apr. 16, 2002 (54) METHOD FOR PREDICTING SEISMIC (56) References Cited EVE TS N U.S. PATENT DOCUMENTS (76) Inventor? Konstalldinos 5- Zamfes, 1830-10TH 4,359,766 A * 11/1982 Waters et al. ............... .. 367/38 Avenue, Ca1gary,A1b9rta (CA), T3C 4,964,087 A * 10/1990 Widrow ............... .. 367/45 018 5,555,220 A * 9/1996 Minto . .. 340/853.9 5,784,334 A * 7/1998 Sena et al. .................. .. 367/47 ( * ) Notice: Subject to any disclaimer, the term of this * _ d b _ patent is extended or adjusted under 35 Cue y exammer U-S-C- 154(k)) by 0 days- Primary Examiner—Van T. Trieu (74) Attorney, Agent, or Firm—Sean W. Goodwin (21) Appl. No.: 09/736,313 (57) ABSTRACT (22) Filed: Dec. 15, 2000 A method for predicting seismic events Wherein measurable (30) FOI‘EigIl APPIiCHtiOII PI‘iOI‘itY Data and calculable parameters relating to alterations in the shape of the geoid, such as centripetal and tidal gravitational Dec. 17, 1999 (CA) ........................................... .. 2292803 effects, and gravitational anomalies related to a buildup of (51) Int. Cl.7 .............................................. .. G08B 21/00 energy at any given point in the earth are incorporated With (52) US. Cl. .................. .. 340/690; 340/601; 340/853.9; Observations from at least tWO previous, subsequent seismic 367/45 events, to calculate the energy buildup required to result in (58) Field Of Search ............................... .. 340/601, 690, a future Seismic event 340/853.9, 853.1, 854.1; 367/38, 45, 47, 86; 324/344, 347, 348 2 Claims, 6 Drawing Sheets U.S. Patent Apr. 16, 2002 Sheet 1 6f 6 US 6,373,396 B2 U.S. Patent Apr. 16, 2002 Sheet 2 6f 6 US 6,373,396 B2 w.QI U.S. Patent Apr. 16, 2002 Sheet 3 6f 6 US 6,373,396 B2 U.S. Patent Apr. 16, 2002 Sheet 4 6f 6 US 6,373,396 B2 U.S. Patent Apr. 16, 2002 Sheet 5 6f 6 US 6,373,396 B2 V4122 / ww , i/ f 9/3 W M342 Fig. 5 U.S. Patent Apr. 16, 2002 Sheet 6 6f 6 US 6,373,396 B2 KSAg US 6,373,396 B2 1 2 METHOD FOR PREDICTING SEISMIC BRIEF DESCRIPTION OF THE DRAWINGS EVENTS FIG. 1 is a section through the center of the earth Which FIELD OF THE INVENTION illustrates the effect of polar shift on the corresponding section through the geoid surface; The present invention relates to methods of predicting the FIG. 2 is a section through the center of the earth Which occurrence of seismic events from changes in the earth’s illustrates the effect of polar shift on the forces at a geo equipotential gravitational surface due to polar motion. graphical location on the earth; More particularly, accumulated gravitation shift in geoids FIG. 3 is a side vieW of a truncated ellipsoid earth betWeen successive polar motions is associated With the 10 illustrating rotational planes and rotation vectors of a single accumulation in energy in the earth’s crust Which can be mass on the surface of a geoid; correlated to seismic events. FIG. 4 is a fanciful vieW to illustrate the tidal gravitational BACKGROUND OF THE INVENTION effects of the sun and the moon; FIG. 5 is a plot of the polar motion of the earth over a The majority and most destructive of earthquakes or 15 seismic events are the tectonic quakes Which are a result of selected time period of 1964—1968; a sudden release of energy accompanying a shift or dislo FIG. 6a illustrates tWo geoids spaced in time With partial cation of the earth’s crust (shalloW) and in the upper mantle indications of the many intermediate incremental geoids (deep). Which could be calculated therebetWeen and the magnitude of the change in gravitational effect; Shifts in the earth’s crust create a potential energy, Which 20 is occasionally released in a seismic event. Due to the FIG. 6b is a pair of charts Which respectively illustrate; a devastating results of earthquakes, particularly those occur plot of the Ag over each time increment betWeen tWo seismic ring in populated areas, there have been concerted efforts to events at t1 and tn and accumulates over time future event at predict such events. tm, and a plot of the accumulation of energy betWeen events. There are knoWn areas of frequent seismic activity such as 25 DETAILED DESCRIPTION OF THE geological locations having faults. Monitoring stations are PREFERRED EMBODIMENT provided at these locations Which, at best, provide Warning of an immediately impending event. Monitoring primarily It is not neW that gravitational anomalies affect the shape consists of recording geophysical precursors such as P-Wave of the equipotential surface of the earth. This undulating velocity, ground uplift, radon emission, rock electrical resis 30 surface is also knoWn as a geoid. Effects Which alter the tivity and Water level ?uctuations. These precursors can shape of the geoid include the centripetal effect of the earth’s have lead times of one day through to several years depend rotation (an equatorial bulge) and tidal gravitational effects. ing upon the magnitude of the upcoming event. The surface undulates due to local gravitational anomalies. Some approaches to obtaining more advance notice or While the surface of the ocean provides a good approxima prediction of future events includes statistical analysis of the 35 tion of the geoid, the shape of the geoid can also be history of earthquakes in a given location so as to determine calculated over a land mass. These undulations are conven Whether there is a recurrent, or cyclical pattern to the events. tionally determined as departures from the theoretical ellip These methods can provide a statistical value, for eXample, soid. a 70% probability of an event happening every 100 years, The geoid is associated With the earth’s orientation Which 40 but still leave an uncertainty of tens of years. varies according to an annual elliptical component and a Generally hoWever, there is a need for an earlier Warning Chandler circular component With a period of about 435 system and one Which can be tied to knoWn and independent days. The variation is due in part to annual spring melt factors. cycles and tidal effects Which eXert a torque on the earth. This torque results in precession of the earth’s rotational 45 SUMMARY OF THE INVENTION aXis. The precession is not a steady process hoWever, there Using the motion of the earth’s poles, a series of succes being discontinuities or a lull in the precession each time the sive geoids can be determined. The shift betWeen incremen tidal mass crosses the equatorial plane. Further, beyond the tal geoids provides information necessary to determine tidal precession, the earth itself undergoes a free, Eulerian precession, some times called a “free nutation” or the changes in gravitational anomalies and ultimately the accu 50 mulation in energy at a given geological location. Knowing Chandler Wobble. the energy Which Was released in a previous seismic event, The earth’s orientation or polar motion is monitored. One the geoidal shift method of the present invention can be used such monitoring service is the International Earth Rotation to monitor and predict a subsequent seismic event. Service (IERS) located at the US. Naval Observatory. It has In a broad form of the invention, a method is provided for 55 been determined that the earth’s aXis has scribed a conical predicting seismic events comprising: determining a ?rst path of about 235° in about 26,000 years. geoid surface at ?rst instance in time; determining succes The major sources of energy for seismic events are the sive geoid surfaces for successive and incremental instances gravitational anomalies. Gravitational anomalies are gener in time; determining an incremental energy associated With ated by differences betWeen the gravity equipotential sur each incremental shift betWeen the successive geoid sur 60 faces and the centripetal force of the earth’s rotation (r002). faces; accumulating energy associated With the incremental This value, of course, varies With latitude from Zero at a pole shifts; and comparing the accumulated energy With a pre to a maXimum at the equator (r=R cos (1)). A shift in aXis of determined energy Which has resulted in a seismic event as the earth’s rotation changes the radius of rotation (a vector being indicative of the likelihood of a future seismic event. of rotation force is a component of the gravitation vector). Preferably, the pre-determined energy for a seismic event is 65 Variation of sea-level gravity from a theoretical ellipsoid determined by establishing measures of the energy released Was ?rst set forth, by mid-18th century scientist Alexis in a previous seismic event. Clairaut, as a function of latitude. Adoption of internation US 6,373,396 B2 3 4 ally agreed upon constants improved the accuracy of the energy required to cause the earthquake. This energy rep gravity calculations. Using the expression for gravity, relat resents energy accumulated from factors including those ing mass and distance, increased distance from the earth’s caused by the shift of axis of the earth betWeen said events. center can be added to the calculation. At sea level, the From the knoWn energy level, one can predict a similar gradient is about —0.3086 milligal per meter of elevation energy Which Will trigger or initiate a subsequent seismic increase. Calculations for such uniform changes in elevation event at that same location. are also knoWn as the Free-Air Anomaly.
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