Editing Gerard De Geer (section)

== Biography ==
Baron Gerard Jacob De Geer comes from a well-known [[List of Swedish noble families|Swedish aristocratic family]] of [[Duchy of Brabant|Brabant]] origin, who had emigrated to Sweden in the early seventeenth century. His family included prominent industrialists and politicians. His father [[Louis Gerhard De Geer|Louis]] and older brother [[Gerhard Louis De Geer|Gerhard Louis]] served as the [[Prime Minister of Sweden]].{{sfn|Bailey|1943|p=475}}

Gerard Jacob was born on 2 October 1858, in [[Stockholm]] in the family of Baron Louis Gerhard de Geer, at that time the [[Minister for Justice (Sweden)|first Minister of Justice]] in the [[Swedish government]], and Carolina de Geer, née Countess Wachtmeister. Since 1869 he studied at primary school, and since 1873 - at the [[:sv:Stockholms gymnasium|Stockholm gymnasium]]. In 1877, de Geer entered [[Uppsala University]]. In May 1879 he graduated and received a Bachelor of Arts degree.{{sfn|Madsen|1943|p=281}}<ref>{{cite web
 |url         = https://sok.riksarkivet.se/sbl/Presentation.aspx?id=17350
 |title       = Gerard Jacob de Geer
 |author      = Lennart von Post
 |author-link      = Lennart von Post
 |work        = [[Svenskt biografiskt lexikon]]
 |access-date  = 12 July 2020
 |language        = sv
}}</ref>

In 1878, De Geer became an employee of the [[Geological Survey of Sweden]], initially freelance,{{sfn|Madsen|1943|p=281}} then, since 1882, as an assistant to a geologist, and since 1885, a full-time geologist.{{sfn|Madsen|1943|p=283}} At this time he started to study the late [[Quaternary]] deposits and landforms of southern Sweden. In 1897, he left his job in the geological service for the position of professor of general and historical geology at [[Stockholm University]].{{sfn|Madsen|1943|p=286}}

In 1882, on the recommendation of [[Otto Martin Torell]], de Geer participated in the Swedish expedition to [[Spitsbergen]] as part of the first International Polar Year as a staff geologist.{{sfn|Madsen|1943|p=283}} This marks the beginning of many years of research on the modern glaciation of the Svalbard archipelago: in total he took part in six expeditions to Svalbard (1882, 1896, 1899, 1901, 1908 and 1910).<ref name = Stadnamn>{{cite web
 |url         = http://stadnamn.npolar.no/stadnamn?q=de+geer
 |title       = Place names in Norwegian polar areas
 |website     = placenames.npolar.no
 |publisher   = [[Norwegian Polar Institute]]
 |access-date  = 26 February 2015
}}</ref>

Gerard de Geer remained a lecturer at the Department of Geology at the University of Stockholm from 1897 to 1924.{{sfn|Bailey|1943|p=475}} At the university, he served as rector (1902-1910) and vice-chancellor from (1911-1924).{{sfn|Cato|Stevens|2011|p=2}} In addition, De Geer was a member of the [[Parliament of Sweden|Swedish Parliament]] from 1900 to 1905.{{sfn|Cato|Stevens|2011|p=2}}

The pinnacle of de Geer's scientific career can be considered the receipt of the presidency of the X International Geological Congress, held in Stockholm in 1910. At first he took part in the preparation of the Congress as vice-chairman of the preparatory committee, and from May 1907 - as chairman of the executive committee. Within the framework of the congress, he delivered the now classic lecture "A geochronology of the last 12000 years".<ref name = Sundquist_2004>{{cite journal |last1=Sundquist | first1=Björn |last2=Nordlund|first2=Christer |title= Science and Honour: The 11th International Geological Congress in Stockholm 1910 |journal= Episodes  |year= 2004 |publisher=IUGS  |volume= 27 |issue=  4|pages = 284–292 |doi =  10.18814/epiiugs/2004/v27i4/008|language= en |doi-access=free }}
</ref> He began this lecture with such words "Geology is the history of the earth, but hitherto it has been a history without years." At the congress De Geer formally introduced the term [[varve]] defining it as any annual sedimentary layer, and also proposed that the term [[geochronology]] be restricted to varve dating, other existing techniques being less accurate and precise. By then, observations of the [[stratigraphy|stratigraphic]] relationship between varved sediment and recessional [[moraine]]s, and the correlation of varve sequences between geographically distant sites, added more compelling evidence to De Geer's essentially circumstantial speculation. The geological community accepted that the couplets were unlikely to represent any period other than the year. In addition, before the start of the Congress, De Geer conducted an excursion for 65 delegates from 14 countries, within the framework of which he examined the [[Dicksonfjorden]] on Spitsbergen.{{sfn|Madsen|1943|p=288}}