Measurements of Active Tectonic Deformation Along the Pacific Coast of Mexico

该项目的目的是获取墨西哥太平洋沿岸格雷罗海岸沿岸地貌和地质记录（地层学）的实地数据、放射性碳数据和暴露年龄，以得出这一高地震区的长期构造变形率。目前正在综合使用地貌学、地层学-沉积学、放射性碳和宇宙成因等方法，评估地貌和沿海沉积序列中保留的构造变形的长期记录。地貌和地质的综合评估，洞察到第四纪的长期变形率的活动收敛边缘。测量包括精确测量和确定沿海景观和地层中指示构造变形的标志物的年代。具体目标是从格雷罗沿海地区的地貌和地层研究中得出构造变形率，以建立沿海构造的长期变形率模型，并与从大地测量和地震数据得出的短期变形率进行比较。1）研究表明格雷罗海岸构造位移的地貌标志（如海洋阶地、露出的潮汐缺口、海洋台地、海滩脊）。其中包括遥感和地理信息系统分析、地貌标志高程实地测量、制图、放射性碳和收集样品的宇宙生成年代测定，以确定出现的地貌的年代; 2）沿海地区的地层沉积学和放射性碳研究，以评估长期地壳运动的记录; 3）综合资料分析和建立海岸构造长期速率变形模型。模拟和量化高地震潜在性地区的长期（第四纪）构造变形速率，在该地区，历史地震（如米霍坎1985年事件）造成3000人死亡和数亿美元的经济和财产损失。 格雷罗缺口代表了一个高地震潜力的地区，可能积累的应变可以在大规模地震中释放。

This project is to obtaining field data, radiocarbon data and exposure ages on coastal landforms and the geologic record (stratigraphy) along the Guerrero Coast, on the Pacific coast of Mexico, to derive long-term rates of tectonic deformation in this area of high seismic. combining geomorphic, stratigraphic-sedimentological, radiocarbon and cosmogenic approaches are being used to assess the long-term records of tectonic deformation retained on the landscape and in coastal sediment sequences. Comprehensive assessment of the geomorphology and geology give insights into the Quaternary long-term rates of deformation of this active convergent margin. Measurements include precise surveying and dating of markers in the coastal landscape and in the stratigraphy indicative of tectonic deformation. The specific objective is to derive rates of tectonic deformation from geomorphic and stratigraphic studies of the Guerrero coastal area to generate a long-term deformation rate model of coastal tectonics and compare with the short-term rates derived from geodetic and seismic data.The specific work being carried out is: 1) Studies of geomorphic markers indicative of tectonic displacement (e.g. marine terraces, emerged tidal notches, marine platforms, beach ridges) on the Guerrero coast. These include remote sensing and GIS analysis, field surveying of geomorphic markers elevations, mapping, radiocarbon and cosmogenic dating of collected samples to determine the ages of emerged landforms; 2) Stratigraphic-sedimentological and radiocarbon studies of the coastal areas to assess the records of long-term crustal movements; 3) Comprehensive data analysis and development of a long-term rate deformation model of coastal tectonics.This work adds to the understanding, modeling and quantifying long-term (Quaternary) rates of tectonic deformation in an area of high seismic potential where historic earthquakes such as the Michoacan 1985 event caused 3000 deaths and hundreds of millions of dollars in economic and property losses. The Guerrero gap represents an area of high seismic potential, probably accumulating strain that could be released in a large magnitude earthquake.