Jens Esmark

Jens Esmark (1763–1839) was an expert mountain climber and professor of mineralogy who contributed to many of the initial discoveries and conceptual analyses of glaciers, specifically the concept that glaciers had covered larger areas in the past.

History

In 1798 Esmark was the first person to ascend Snøhetta, highest in the mountain range Dovrefjell in southern Norway. [cite web
url=http://www.visitnorway.com/templates/NTRproduct.aspx?id=173612&lang=EN
title=Snøhetta
publisher=
accessdate=2007-01-18] The same year he lead the first expedition to Bitihorn, a small mountain in the southernmost outskirts of Jotunheimen, Norway. In 1810 he was the first person to ascend the mountain Gaustatoppen in Telemark, Norway.

Professor Esmark theorized in 1824 that glaciers had once been larger and thicker and had covered much of Norway and the adjacent sea floor. [cite book
first= William J.
last=Burroughs
authorlink=
coauthors=
year= 2005
title= Climate Change in Prehistory: The End of the Reign of Chaos
edition=
publisher=Cambridge University Press
location= Cambridge
pages= p. 22-24
id= ISBN 978-0521824095 ] He also attributed erratic boulders and moraines to glacial transportation and deposition. He first recognized glaciers as a powerful agent of erosion that had carved the Norwegian fjords. [cite web
url=http://academic.emporia.edu/aberjame/histgeol/agassiz/glacial.htm
title=Birth of the Glacial Theory
publisher=academic.emporia.edu
accessdate=2007-01-18]

Professor Esmark was also an important figure in the history and cultural heritage of mineralogy. [cite web
url=http://www.nhmus.hu/~pappmin/publ_history.html
title=Publications related to the history and cultural heritage of mineralogy
publisher=
accessdate=2007-01-18] On the island of Løvø, Norway, his son, Hans Morten Thrane Esmark, found the first specimens of a black mineral, thorite, from which the element thorium is derived. [cite web
url=http://www.bbc.co.uk/dna/h2g2/A3768861
title=Thorium
publisher=BBC.co
accessdate=2007-01-18] His son also provided him with a new mineral which he found in Arendal, Norway. In 1806 he named datolite, from the Greek word meaning "to divide". This was a reference to the granular structure of the first specimens studied. [cite web
url=http://www.gemologyproject.com/wiki/index.php?title=Datolite
title=Datolite
publisher=The Gemology Project
accessdate=2007-01-18]

Notes

References

*Cunningham, F.F. 1990. James David Forbes: Pioneer Scottish glaciologist. Scottish Academic Press, Edinburgh
*Burroughs, William James, Climate Change in Prehistory: The End of the Reign of Chaos, Cambridge University Press (2005) ISBN 978-0521824095

External links

* [http://www.preikestolen.no/tekstsider_reiseliv.cfm?id=4&lang=eng Forsand]
* [http://www.cst.cmich.edu/users/dietr1rv/datolite.htm Photos of Datolite]
* [http://nautilus.fis.uc.pt/st2.5/scenes-e/elem/e09010.html Thorium: History]