DATING OF EARTHQUAKES - TREE-RING RESPONSES TO THE CATASTROPHIC EARTHQUAKE OF 1887 IN ALMA-ATA, KAZAKHSTAN

A tree ring study of Picea schrenkiana Fisch. et Mey. growing on the northern slopes of the Zaileeskii Alatau mountain ranges near the epicentre of the 1887 earthquake was carried out to evaluate the effect of strong earthquakes on tree growth patterns. Tree growth was found to be severely reduced following the earthquake, generally for a period of three to four years, but in certain cases growth suppression lasted for up to 15 years. The long-term growth suppression is attributed to the tilting of trees as a result of the earthquake. Such studies in earthquake-prone zones can be of value in identifying and dating prehistoric earthquake events.