Use of GIS for 3D soil modeling and application to seismic hazard assessment

The great Michoacan earthquake of 1985 in Mexico City illustrates the importance of site effects in determining the distribution of earthquake damage (Celebi et al, 1987). Ground acceleration in the lakebed area of Mexico City, located about 400 km from the earthquake source, was greatly amplified, reaching a level even higher than the one produced near the epicenter. Other recent earthquakes, like the 1995 Kobe earthquake (Kaneko et al, 1996), have confirmed that site effects play a predominant role in the distribution of damage during earthquakes. Ideally, the effect of subsoil conditions on the site hazard can be determined by a detailed microzoning study. However, sismic hazard assessment studies in developing countries or in rural areas of industrialized countries often face the following difficult circumstances: a) there is a lack of sufficient information and data; b) existing information can be difficult to find because it is stored in many different locations, usually by the public or private organizations that produced it; and c) the levels of reliability and completeness of the existing data vary widely. Alternate methodologies that address these issues need to be developed in order to more accurately assess the seismic hazard and risk of non-industrialized countries. In this paper, GIS technology with 3D capabilities is used to collect, combine, and analyze available information in the production of an analytical soil model. The preparation of a soil model for the City of Quito, Ecuador, is presented as an example of the proposed methodology. The modeling of the subsurface soil was required for the estimation of damage due to future hypothetical earthquakes and carried out in the Quito, Ecuador Earthquake Risk Management Project. Due to the absence of available GIS technology at the time of the project, the 3D, analytical, soil model has been prepared as part of follow up efforts to refine and update the results of the Quito, Ecuador Earthquake Risk Management Project

Lessons for Central Asia from Armenia and Sakhalin : Strategies for urban, earthquake risk, management for the Central Asian Republics

Central Asia's earthquake activity has long benn recognized as one of the highest in the world, but the extreme vulnerability of its soviet-area residential buildings was realized only after two recent earthquakes otuside the region. This document refers to the urgency of addressing Central Asia's urban earthquake risk. This report summarizes the findings and recommendations of a workshop held in Almaty, Kazakhstan, from October22-25, 1996. It involved more than 50 experts from fields of seismology, earthquake resistant design, and urgency response from across Central Asia and around the world