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In the Bulletin 001 were given forecasts for the strong earthquakes in SS Java to the beginning December 2008. In the forecast for the strong earthquakes from М≥6.6 it communicated: " … Situation in the system is not dangerous, but is unstable. Trajectory is located in the attractor. Probability of strong earthquake in system 4% (on entropy 19%, and on cumulative energy 22%). Prior to the end of 2010 the trajectory will be located near the oceanic zone of instability on 100 km southern from the West of Java. Is here possible earthquake from M6.6, which does not present danger for populating…".

The oceanic zone of instability, near which was located the trajectory in the attractor, this close the diagonally directed dotted region A' , shown on Fig.1. In the region A' were located the previous strong earthquake in system 2006.07.17, М=7.2 forecast by us, (Akopian S.Ts.). To Fig.1 is shown potentially hazardous zone A for earthquakes from М≥7.8. By August 2009 probability grew to 6% (25% and 23%) (see Fig.2), but trajectory yet it did not suffice to the unstable region of attractor for А' region. Strong earthquake occurred on September 2, 2009 ☼ 100 km eastern-northeastern from the expected zone (see Fig.1). It occurred earlier than the time, out of the expected region and with the larger magnitude. In the language of the method of seismic entropy it occurred with the scarcity of cumulative energy and entropy of indicator-earthquakes. This it indicates that the seismic cycle started from the middle of 2006 was not sufficient for its preparation. Let us try to understand why?

	JAVA (Indonesia), Мs≥7.8 System of IV level (badly determined)
	Situation in the system is not yet dangerous. Occurs the preparation of strong earthquake from Ms>7.8. Undoubtedly, earthquake dated September 2, 2009 will contribute and it will accelerate the preparation of catastrophic earthquake. As before, the southwest of Java remains potentially dangerous. Probability of strong earthquake in the system on entropy 0.3%, and on cumulative energy 5%. To inhabitants of the east of island Java and Bali within the next few years catastrophic earthquake from Ms>7.8 it does not threaten. Let us note that the quality of forecast in the system is poor.	P_K=4.85% P_W=0.34% Р=0.02%
	JAVA (Indonesia), Мs≥6.6
	Earthquakes with 6.6≤М<7.8 is not expected. In this system earthquake dated September 2, 2009 we assume as strong and we interrupt seismic cycle. It occurred with the scarcity of cumulative energy and entropy of indicator-earthquakes with probability P=6% (on entropy 25%, on cumulative energy 23%). To inhabitants of the east of island Java and Bali within the next few years strong earthquake from Ms> 6.6 and tsunami does not threaten.	P_K=0% P_W=0% Р=0%
	JAVA (Indonesia), Мs≥5.8
	The situation in subsystems - West and East of Java. (Subsystems according to the sizes they are small, they control Java island and 100 km coastal part in the East and West). Earthquake dated September 2, 2009 discharged western subsystem. Probability of strong earthquakes from 5.8≤Мs<6.6 it is small in the West of Java. In the next year will be observed activation of indicator-earthquakes from M5.0-5.6. It is potentially dangerous on the western tip of Java. In the East Java situation is stable, there is no seismic danger. Residents of the islands of Java and Bali within the framework controlled region strong earthquake from 5.8≤Ms<6.6 (on the semblance of an earthquake Yogyakarta 2006) is not threatened. Prior to the end of 2010 will be observed the activation of indicator-earthquakes from М5.0-5.5.	P_K=0% P_W=0% Р=0% P_K=21% P_W=33% Р=7%

September 2, 2009 earthquake on the southwest from the island Java by the mechanism of source is uncommon for the subduction zones. Tectonics of this region is caused by the north-northeastern motion of Australian plate with a average speed of 6 cm/yr and by its sinking under the Sunda plate. The sources of strong earthquakes, in essence, are timed to the contact plane of these plates in the zone of subduction and have the reverse faulting (thrust) mechanism on these planes. Earthquake on September 2 occurred at the depth of 50-60 km; it also had the reverse faulting mechanism (see Fig.3); however, its plane of slip it differs significantly from the mechanisms of earthquakes, proceeding on these surfaces. At this earthquake occurred reverse faulting motions on the break within the subducting Australia plate, oriented perpendicularly to Java trench (see Fig.3 and 4). If the first, typical for the subduction zones, strong earthquakes appear as a result compressive stresses in the direction of Australian plate motion (on the thrust plane of Australian plate beneath the Sunda plate), then the second occur as a result compressive stresses, directed perpendicularly to direction of plate motion, that appear as a result of the bend of Australian plate in the zone of Java trench (there is a view of island arc, a cylindrical bending of rigid plates plunging). On longitudinal faulting indicate the distribution of the aftershocks of this uncommon earthquake (see Fig.3).

DIFFICULTIES OF THE FORECAST OF EARTHQUAKE on September 2, 2009, Java. The basic strong earthquakes in Java, which we is forecast on the basis of the method of seismic entropy, are caused by large-scale motions between the Australia and the Sunda plates within the framework SS Java. They relate to the reverse faulting type with the small angles of dipping. Earthquakes of such type are regular, frequently they are repeated and are basis for constructing the energy and track diagrams in the method of seismic entropy. Interplate faulting earthquakes, type of earthquake dated September 2, 2009, are relatively rare events. The magnitudes of such earthquakes can reach 7, but hardly they will exceed 7.3 (since the surfaces areas of slip are small). A stress drop in them it is great, in comparison with the basic earthquakes near the subduction interface. This is, apparently, connected with the fact that stress of friction or strength of the plate rocks substantially higher than on its boundaries. Accumulation and release of stresses within the sinking Australia plate within the framework SS Java, that generate with longitudinal faulting, are not connected directly with the motions of plate, and they occur for the wide intervals of time, than the duration of the seismic cycles, which we control. This indirectly indicates the fact that the earthquake on September 2 occurred with the scarcity of the controlling parameters on the track diagram. The sequences of such earthquakes as earthquake dated September 2 are extremely irregular in comparison with the sequences of events, typically for subduction zones; therefore they can be forecast with the adequate accuracy after the accumulation of the necessary statistics.

Summing up, we can say that the earthquake dated September 2, 2009, M=7 was strongest in its classification and such earthquakes of extensive damage than that which was observed, they cannot apply. Specifically, the special features of the mechanism of this earthquake described above were the reason for the fact, that the earthquake did not excite the fatal waves of tsunami and managed with relatively small destruction and victims.

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