ENGINEERING GEOLOGIC AND LIQUEFACTION SUSCEPTIBILITY ANALYSIS OF THE INNER VALLEY, RIO GRANDE BASIN, ALBUQUERQUE, NEW MEXICO

Albuquerque lies within the seismically active Albuquerque Basin, one of the largest tectonic basins within the Rio Grande Rift. Although there have been few large historical earthquakes, there are many Quaternary faults in the Albuquerque area. Therefore, there is a potential for future earthquakes and liquefaction related damage in the region. This study area is restricted to the Inner Valley of the Albuquerque Basin and extends from the southern boundary of Sandia Pueblo to the northern boundary of Isleta Pueblo. The Inner Valley is a 4.5 to 6.5 km (2.8 to 4 mi) wide lowland valley and floodplain that is underlain by unconsolidated, uncemented, and predominantly sandy alluvium. Clay and gravel lenses are locally present but generally not laterally persistent. The shallow water table in this region intersects the ground surface along the Rio Grande and gently slopes away from the river in both directions. A database of well log information pertinent to engineering geologic and liquefaction susceptibility analyses has been created for use in liquefaction susceptibility studies. Data from 383 boreholes are included in this database. This database is the groundwork for an ongoing geostatistical study of the spatial distribution of sediments within the Inner Valley of the Albuquerque Basin and a GIS based liquefaction susceptibility analysis. Results from this study will be compared to those from a previous liquefaction potential analysis of the Rio Grande valley.