Forecast mega-earthquake in California, Ms? 7.8

The reports of 11 May 2009 and 12 May 2009 was a forecast of strong earthquakes in southern California based on the SS California with threshold magnitude Mp = 7.5. It was predicted that in southern California can be prepared earthquake with M = 7.7-7.9 from 2014 to 2016. segment on the San Andreas Fault (from Palmdale in San Bernardino to Riverside). In a communication dated October 4, 2009 was considered a possible scenario for the preparation of an earthquake with M = 7.8 in 2011, the segment of the San Andreas Fault Parkfield (Cholame Valley) to Raytvuda (Wrightwood).

I. MEGA SS California, Ms? 7.8. After the catastrophic earthquake in Japan, we considered the possibility of a mega-earthquake in California SS with M? 7.8. Mega SS California belongs to the category of ill-defined. There were three earthquakes in 1690, 1857 and 1906. The earthquake rupture occurred in 1690 from San Bernardino through the Coachella Valley (Coachella Valley) to Salton Cea. Of the three major earthquakes, we can reconstruct the two ended seismic cycle for earthquake Fort Tizhon 1857, M = 7.9, and San Francisco, 1906, M = 7.8 (see Figure 1 and Table 1). Average return period of 108 years. After the earthquake in 1906 was 105. Next on the frequency needs to happen in 2014. Culminating in two seismic cycles, using the values of Chart 1, we define the law of seismic entropy production (see Figure 2):

In May 2011 in the mega system, entropy W = 19.768. Substituting into (1), the energy class of the expected earthquake Ks = 16.947, which corresponds to M = 8.1. Today in Southern California earthquake of energy produced 1.8 times more than in the earthquake of 1857. The gap on the San Andreas Fault in the earthquake in 1857 extends to 300 km from Parkfield (Cholame Valley) to Raytvuda (Wrightwood); horizontal displacement reached 9 meters. With the expected earthquake with M = 8.1, if all the energy in conjunction with the San Andreas fault rupture along a fault that reaches 520 km and an area of 10400 km shifts2, with an average of 5 m Ie progress would amount breaks 1690 and 1857 earthquakes (Fig. 1). Figure 3 shows the track diagram Mega SS California. Of the track diagram shows that earthquake-indicator Kern County (Kern Caunty) in 1952 occurred near the region of instability mega earthquakes. This earthquake is considerably strengthened by the SS and took a track from the attractor (yellow line in Figure 3). By the second half of the 80s track again approached the attractor, but subsequent earthquakes-indicators 1989, 1992 and 1999, again removed the track from the attractor. Since the system is ill-defined, we have calculated the attractor points for earthquake-indicators in 1952 and 1992 (in general this is incorrect):

Of May 2011 K = 17.078. Substituting in Eq (2) is critical values of entropy Wk = 19.800. Lull in seismic entropy reaches this value by February 2014. Thus, the cycle frequency and the critical value of the entropy of an earthquake with M = 8.1 must occur before March 2014 in the area of Sun Fig.1.

Fig.1. Mega SS California. Shows focal area of three strong earthquakes. In the area of Sun is preparing a catastrophic earthquake M = 8.1.

 

Fig.2. Energy diagram Mega SS California. Prepared by the catastrophic earthquake M = 8.1. Shows a hypothetical location of earthquake 1690.

 

Since Mega SS California ill-defined, we performed a comparative analysis of preparation mega earthquakes in California with other systems. From all we have found similar values SS had three tracks preparations subduction zone earthquakes in Japan and the Kuril Islands. Most of them had similar values track earthquake preparation November 15, 2006, M = 8.1 in the SS Central Kurils. Figure 4 shows the center of the earthquake and the contours of the SS Central Kuriles map rotated clockwise by 90 °. The preparation time of the earthquake 91 years. Shifts from 1 to 9 m (average 2.5 m to a depth of 30 km) occurred on the subduction plane area 250h100 km2= 25,000 km2.
Figure 5 shows a portion of the track of the earthquake combined with the track preparation of the catastrophic earthquake in Southern California. Like the earthquake in 1952 in the case of California's earthquake-indicator 1951, M = 7.4 essentially rejected track from the attractor and only to 2006, he again approached the instability region.

Comparative analysis shows that despite a few different pleyttektonicheskie situation in Southern California and the Kuriles prevailing dynamic situation in Southern California is comparable to the subduction zone of the central Kuriles. In contrast, preparations of earthquakes in 1857 and 1906, the system requires a tremendous effort not only to transform movements, but also to overcome the thrust fault / podvigovyh processes. 2006 earthquake in the Kuril Islands occurred at W = 19.766 K = 17.053. The coordinates of the track in case of California in May 2011 have already surpassed these values, but the critical value of entropy is difficult to assess. Attractor for the Kuriles on points in 1951 and 2006 is given by: K = 0.697W +3.269. If we take it as a basis for the California track, the track reaches the critical value of entropy Wk = 19.802 in August 2014, and the hypothetical center of expected earthquake in Southern California would have the form shown in Figure 6.

Because, in contrast to the Kurils, California average horizontal displacement will be more, presumably by half (5 m), the total area of progress is only half of the order of 12,000 km2.

In fact, taking into account the structure of the fault, the situation will be in between as described in paragraph I and II. The total length of the fault movements distributed between the San Andreas Fault (70%) and other faults (Sierra Madre, 13%, 9% of San Jacinto, San Gorgon 4%, …). This can result in a cascade of several strong aftershocks in a narrow time interval. Figure 7 shows the expected area of the earthquake with M = 8.1. An earthquake can happen at any time, the final date for the first half of 2014. The forecast of this mega-earthquake removes / replaces the previous predictions made for the SS California with M? 7.5 (see the beginning of the message). Remains in effect that the earthquake in Parkfield can serve as a trigger expected catastrophe.

 

Fig.5. Fragments of track diagrams Mega SS Central California and was smoking on a plane. Earthquakes in 1952 and 1951. remove tracks from attractors respectively California and the Kuriles (straight lines).

Fig.6. Hypothetical source region prepare mega subduction earthquake in Southern California (the imposition of an earthquake fault zone of the Kuril 2006).

 

 

Fig.7. Predicted focal area mega earthquake with M = 8.1, taking into account the source of the fault and the Kurile earthquake structure of Southern California.

 

 

Source: GeoKveyk.

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