The paper considers the superposition of modified Omori functions as a conditional intensity function for a point process model used in the exploratory analysis of earthquake clusters. For the examples discussed, the maximum likelihood estimates converge well starting from appropriate initial values even though the number of parameters estimated can be large (though never larger than the number of observations). Three datasets are subjected to different analyses, showing the use of the model to discover and study individual clustering features.

An earthquake with a magnitude of 7.6 struck the town of Neftegorsk (population about 3,000) on 27 May, 1995. This paper describes the devastation and the human aspects of the catastrophe of the first week following the quake. A total of 1,995 persons were found dead under the rubble, including 268 children less than 16 years of age. There were 1,144 survivors. A total of 406 person were rescued alive from under the rubble of which an additional 37 persons died in a hospital following rescue. Most of the survivors have been relocated, but some remain in the area. There remains a need for psychological support for the survivors and rescuers.