Brief historical review of the geological cartography in Ecuador.

Abstract

Since 1892, seven versions of the national geological map of the Republic of the Ecuador have been published. In 1892, Dr. Theodor Wolf, of the German Scientific Mission, published the 1st map which included a preliminary geomorphological description. Later, Dr. Walther Sauer with the support of the Universidad Central del Ecuador (Central University of Ecuador), published a 2nd version in 1950, and then an update in 1970, both included oil wells information. In 1969, the Servicio Nacional de Geología y Minería del Ecuador (National Service of Geology and Mining of Ecuador), and Institut Français du Pétrole (French Petroleum Institute), published the 3rd version which included a mineralogical index. The 4th version was developed by the Dirección General de Geología y Minas del Ecuador (General Directorate of Geology and Mines of Ecuador) and Institute of Geological Sciences & Natural Environment Research Council, and was published in 1982, it included a geological model from a plate tectonics approach. Later, in 1993, the Corporación de Desarrollo e Investigación Geológico Minero y Metalúrgica del Ecuador (Geological, Mining and Metallurgical Research and Development Corporation of Ecuador) and the British Geological Survey published a 5th version, which included an overview of mineral occurrences on the Ecuadorian Andes. On the 21st. century, in 2001 was published the 6th version, that consisted of a reviewed national geological map, which included data transferring to the geographical information system ArcGis. Ultimately in 2017, the Instituto Nacional de Investigación Geológico Minero Metalúrgico (National Institute of Geological-Mineral-Metallurgical Research), published the 7th version, incorporating the last updated geological results of previous campaigns. Every version contributed to the understanding of the regional geodynamic framework. Nevertheless, in the last two decades, informal coding of units for the geological cartography, thrived, involving a lack of characterization and descriptions of representative outcrops, along with uncertainties on geochronological control for newly mappable defined units, reduce reliability on the national geological cartography, increasing the uncertainties for the understanding the regional geodynamic framework.