Alexander Logie du Toit FRS ( ; 14 March 1878 – 25 February 1948) was a geologist from

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...

and an early supporter of

Alfred Wegener Alfred Lothar Wegener (; ; 1 November 1880 – November 1930) was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher. During his lifetime he was primarily known for his achievements in meteorology and ...

's theory of

continental drift Continental drift is the hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed. The idea of continental drift has been subsumed into the science of pl ...

Early life and education

Du Toit was born in

Newlands, Cape Town Newlands (Nuweland) is an upmarket suburb of Cape Town, South Africa. It is located at the foot of Table Mountain in the Southern Suburbs of Cape Town, and is the wettest suburb in South Africa due to its high winter rainfall. The neighborhood ...

in 1878, and educated at the

Diocesan College The Diocesan College (commonly known as Bishops) is a private, English medium, boarding and day high school for boys situated in the suburb of Rondebosch in Cape Town in the Western Cape province of South Africa. The school was established on ...

Rondebosch Rondebosch is one of the Southern Suburbs of Cape Town, South Africa. It is primarily a residential suburb, with shopping and business districts as well as the main campus of the University of Cape Town. History Four years after the first Dutch s ...

and the University of the Cape of Good Hope. Encouraged by his grandfather, Captain Alexander Logie, he graduated in 1899 in

mining engineering Mining in the engineering discipline is the extraction of minerals from underneath, open pit, above or on the ground. Mining engineering is associated with many other disciplines, such as mineral processing, exploration, excavation, geology, a ...

at the

Royal Technical College The Royal College of Science and Technology was a higher education college that existed in Glasgow, Scotland between 1887 and 1964, and is the predecessor institution of the University of Strathclyde. Its main building on George Street now serve ...

Glasgow Glasgow ( ; sco, Glesca or ; gd, Glaschu ) is the most populous city in Scotland and the fourth-most populous city in the United Kingdom, as well as being the 27th largest city by population in Europe. In 2020, it had an estimated popu ...

. After a short period studying geology at the

Royal College of Science The Royal College of Science was a higher education institution located in South Kensington; it was a constituent college of Imperial College London from 1907 until it was wholly absorbed by Imperial in 2002. Still to this day, graduates from th ...

in London, he returned to Glasgow to lecture in geology, mining and surveying at the

University of Glasgow , image = UofG Coat of Arms.png , image_size = 150px , caption = Coat of arms Flag , latin_name = Universitas Glasguensis , motto = la, Via, Veritas, Vita , ...

and the Royal Technical College.

Career

In 1903, du Toit was appointed as a geologist within the Geological Commission of the Cape of Good Hope, and he began to develop an extensive knowledge of the geology of southern Africa by mapping large portions of the

Karoo The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe !Orakobab or Khoemana word ''ǃ’Aukarob'' "Hardveld") is a semi-desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its ex ...

and its

dolerite Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grain ...

intrusions, publishing numerous papers on the subject. Subsequently, he mapped the entire Karoo System through the complete stratigraphy from Dwyka

tillite image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...

to the

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...

of the

Drakensberg The Drakensberg (Afrikaans: Drakensberge, Zulu: uKhahlambha, Sotho: Maluti) is the eastern portion of the Great Escarpment, which encloses the central Southern African plateau. The Great Escarpment reaches its greatest elevation – within t ...

. He worked at a furious rate but was known for his painstaking meticulousness, as reflected in his book "Our Wandering Continents". It still bears reading for its creative and closely argued theses in the light of the geology of the day, and is soberingly consistent with modern principles of plate tectonics. In 1920, du Toit joined the Union Irrigation Department as water geologist, and in 1927, he became chief consulting geologist to

De Beers Consolidated Mines De Beers Group is an international corporation that specializes in diamond mining, diamond exploitation, diamond retail, diamond trading and industrial diamond manufacturing sectors. The company is active in open-pit, large-scale alluvial and ...

until his retirement in 1941. In 1923, he received a

grant Grant or Grants may refer to: Places *Grant County (disambiguation) Australia * Grant, Queensland, a locality in the Barcaldine Region, Queensland, Australia United Kingdom * Castle Grant United States * Grant, Alabama * Grant, Inyo County, ...

from the

Carnegie Institution of Washington The Carnegie Institution of Washington (the organization's legal name), known also for public purposes as the Carnegie Institution for Science (CIS), is an organization in the United States established to fund and perform scientific research. Th ...

, and used this to travel to eastern South America to study the geology of Argentina,

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to t ...

and Brazil. As is apparent from his remarks in "Our Wandering Continents", he had requested support for the expedition not on a whim but specifically to test his predictions of correspondences between the geology of both continents. In the event, he was able to demonstrate and follow the predicted continuation of specific features that had already documented in Southern Africa into the continent of South America. Although it might perhaps seem less impressive to the layman, that evidence was far more convincing to the geologist than was the matching of continental shelves. In the light of his research, du Toit published a review of the

stratigraphic Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostra ...

and

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...

evidence from those regions that supported Wegener's ideas, ''A Geological Comparison of South America with South Africa'' (1927). His best-known publication, ''Our Wandering Continents'' (1937), expanded and improved this work and, departing somewhat from Wegener, proposed two original

supercontinent In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leav ...

s separated by the

Tethys Ocean The Tethys Ocean ( el, Τηθύς ''Tēthús''), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean that covered most of the Earth during much of the Mesozoic Era and early Cenozoic Era, located between the ancient continents ...

, a

northern Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a r ...

equator The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can also ...

ial

Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pa ...

and a

southern Southern may refer to: Businesses * China Southern Airlines, airline based in Guangzhou, China * Southern Airways, defunct US airline * Southern Air, air cargo transportation company based in Norwalk, Connecticut, US * Southern Airways Express, M ...

polar Polar may refer to: Geography Polar may refer to: * Geographical pole, either of two fixed points on the surface of a rotating body or planet, at 90 degrees from the equator, based on the axis around which a body rotates *Polar climate, the cli ...

Gondwanaland.

Awards and honours

In 1933, du Toit was awarded the

Murchison Medal The Murchison Medal is an academic award established by Roderick Murchison, who died in 1871. First awarded in 1873, it is normally given to people who have made a significant contribution to geology by means of a substantial body of research and ...

by the

Geological Society of London The Geological Society of London, known commonly as the Geological Society, is a learned society based in the United Kingdom. It is the oldest national geological society in the world and the largest in Europe with more than 12,000 Fellows. Fe ...

, and in 1943, he became a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...

. In 1949, the year after his death, the

Geological Society of South Africa The Geological Society of South Africa (GSSA) is a learned society for geological science that was founded in 1895, making it one of the oldest such societies in Africa. The GSSA publishes the peer-reviewed scientific journal, the '' South Afric ...

inaugurated a biennial lecture series in his honour that continues to the present day. In 1973, a 75 km

crater Crater may refer to: Landforms * Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet * Explosion crater, a hole formed in the ground produced by an explosion near or below the surf ...

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...

(71.8°S, 49.7°W) was named "Du Toit" in recognition of his work.Du Toit crater
Google Mars, retrieved 10 July 2007

Significant works

* du Toit, A.L. (1926) ''The Geology of South Africa'', Oliver & Boyd, London, UK * du Toit, A.L. and Reed, F.R.C. (1927) ''A Geological Comparison of South America with South Africa'', Carnegie Institution of Washington, Washington, USA * du Toit, A.L. (1937) ''Our Wandering Continents; An Hypothesis of Continental Drifting'', Oliver & Boyd, London, UK

References

External links

Biography
(Charles H. Smith,

Western Kentucky University Western Kentucky University is a public university in Bowling Green, Kentucky. It was founded by the Commonwealth of Kentucky in 1906, though its roots reach back a quarter-century earlier. It operates regional campuses in Glasgow, Elizabethtow ...

)
Alexander du Toit's map of two ancient supercontinents
(more detail

Hartebeesthoek Radio Astronomy Observatory)
Alexander du Toit papers and letters archive
(

University of Cape Town The University of Cape Town (UCT) ( af, Universiteit van Kaapstad, xh, Yunibesithi ya yaseKapa) is a public research university in Cape Town, South Africa. Established in 1829 as the South African College, it was granted full university statu ...

) {{DEFAULTSORT:Du Toit, Alexander 1878 births 1948 deaths South African geologists Tectonicists University of Cape Town alumni Alumni of Diocesan College, Cape Town Fellows of the Royal Society Presidents of the South African Archaeological Society Presidents of the Geological Society of South Africa