Measurements of Active Tectonic Deformation Along the Pacific Coast of Mexico

该项目旨在获取墨西哥太平洋沿岸格雷罗海岸海岸地貌的野外数据、放射性碳数据和暴露年龄以及地质记录（地层学），以得出该地区高地震区构造变形的长期速率。结合地貌学、地层学-沉积学、放射性碳和宇宙成因的方法正在被用来评估在景观和海岸沉积物序列中保留的构造变形的长期记录。对地貌和地质的综合评估使我们对这一活动辐合边缘第四纪的长期变形速率有了深入的了解。测量包括对海岸景观和指示构造变形的地层学标志进行精确测量和定年。具体目标是从格雷罗海岸地区的地貌和地层学研究中得出构造变形率，从而得出海岸构造的长期变形率模型，并与大地测量和地震数据得出的短期变形率进行比较。具体工作是：1)研究格雷罗海岸指示构造位移的地貌标志（如海相阶地、涌现潮沟、海相台地、海滩脊）。其中包括遥感和地理信息系统分析、地貌标志海拔的实地测量、制图、放射性碳测定和宇宙起源定年，以确定出现地貌的年龄；2)沿海地区的地层-沉积学和放射性碳研究，评估长期地壳运动记录；3)综合资料分析，建立海岸构造长期速率变形模型。这项工作增加了对高地震潜力地区的长期（第四纪）构造变形率的理解、建模和量化，该地区的历史地震，如1985年米却肯事件，造成3000人死亡和数亿美元的经济和财产损失。格雷罗断裂带代表了一个高地震潜力地区，可能积累了在大地震中释放的应变。

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.