Lake level change, climate, and the impact of natural events: the role of seismic and volcanic events in the formation of the Lake Patzcuaro Basin, Michoacan, Mexico

摘要

In Central Mexico, lake-level change is commonly used as a proxy for climatic fluctuation. Lacustrine sequences are not stable units, however, and have been dramatically impacted by processes related to the evolution of the Mexican Volcanic Belt (MVB) and the fragmentation of the southern part of the North American plate including volcanism, tectonic action, landslides, and human activity. One notable example is the Lake Patzcuaro Basin, Mexico, which has one of the most intensively studied paleoenvironmental records in Latin America. Geologic processes have altered the lacustrine sequence in the southwest portion of the lake basin during the last 48,000 years. These include volcanic activity, major uplift, landslides and related tsunamis, and earthquakes. This new record has important implications for interpretations of climatic events in Central Mexico during the Pleistocene, and the impact these may have had on human settlement in the region.