Douglas James Shearman

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Douglas James Shearman (born July 2, 1918 in Isleworth , Middlesex , † May 12, 2003 in Cassington , Oxfordshire ) is a British geologist and sedimentologist who has made significant contributions to the study of evaporites and other sediments in arid climates .

Life

Shearman began his education in Hounslow , a London suburb. The family moved to Southend-on-Sea in the county Essex , where the students in the estuary of the River Thames roamed. After graduating from school, he began training at the Post Office , which was interrupted in 1939 when he was called up for service in the Navy during World War II. During his basic training in Dover , he became acquainted with geology through a comrade who was studying fossils in a rock fragment . He did his military service as a radio officer on a minesweeper in the North Atlantic.

His geological career began in 1946 when he enrolled at the University of London's Chelsea Polytechnic . After a good degree as a structural geologist , he received the post of Assistant Lecturer at Imperial College in London in 1949, at the request of HH Read , where he gave lectures on sedimentology, an area that would determine his further career. Although he never completed his doctoral thesis on the structure and geology of North Devon , he was first Lecturer in 1951 , then Senior Lecturer (1963) and Reader (1971) before being made an honorary doctorate for his services and professor of sedimentology in 1978 . Shearman has been retired since 1983 .

Research activity

From the mid-1950s to the beginning of the 1960s, Shearman and his group investigated the limestones and dolomites of the French Jura . The scientists developed coloring methods that made it possible to differentiate between the generations of cements found in these rocks under the microscope . Through the investigation of trace elements and the use of other techniques, the working group gained insight into the processes that took place in the dolomitization and dedolomitization of limestones. A second focus of Shearman's work during this period was the intertidal deposits of the wash on the east coast of England.

Shearman later extended his research on tidal and intertidal sediments to areas outside of England. In the course of the work on the pirate coast on the Arabian Gulf (today United Arab Emirates ), it was possible to prove that the anhydrite , which was previously only known from older rocks , is still formed today, among other things in tidal environments. The special formation conditions of such and related sediments of the intertidal zone are now assigned to the facies area of the coastal Sabcha . Shearman also examined similar sediments in Baja California and Canada using stratified intertidal salt deposits . The results of his investigations into evaporitic sediments led Shearman to the conclusion that the mostly fine stratification of the sediments is not due to the evaporation of sea water, which according to the then generally accepted view should produce a thin layer of evaporitic minerals every day in the tidal and diurnal rhythm. Rather, the fine stratification existed before the evaporation and was created by biological processes ( algae mats, etc.), so that finely stratified limestone was created. The displacement of material from these already deposited rocks by gypsum , anhydrite and salt only took place after the limestone was deposited and later.

He finally applied the findings of his investigations into intertidal sediments to the exploration for crude oil , the deposits of which are often associated with evaporites such as anhydrite or salt.

Honors and prizes

literature

Web links

Individual evidence

  1. ^ Professor Douglas Shearman, Unorthodox and inspiring geologist. Obituary for Shearman, The Independent , Friday May 23, 2003.
  2. ^ Lyell Fund. Website of the Geological Society.
  3. ^ Graham Evans: Obituary of Douglas James Shearman: Bsc. Dsc. 1918-2003 . In: Earth and Environmental Science, Carbonates and Evaporites . Volume 18, No. 2 , 2003, p. 171-174 , doi : 10.1007 / BF03176236 .
  4. ^ Lyell Medal. Website of the Geological Society.
  5. ↑ Wollaston Medal. ( Memento of the original from June 5, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Website of the Geological Society.  @1@ 2Template: Webachiv / IABot / www.geolsoc.org.uk
personal data
SURNAME Shearman, Douglas James
BRIEF DESCRIPTION British geologist and sedimentologist
DATE OF BIRTH July 2, 1918
PLACE OF BIRTH Isleworth , Middlesex
DATE OF DEATH May 12, 2003
Place of death Cassington , Oxfordshire