Felix Andries Vening Meinesz
Encyclopedia
Felix Andries Vening Meinesz (The Hague
July 30, 1887 - Amersfoort
August 10, 1966) was a Dutch geophysicist
and geodesist
. He is known for his invention of a precise method for measuring gravity. Thanks to his invention, it became possible to measure gravity at sea, which led him to the discovery of gravity anomalies
above the ocean floor. He later attributed these anomalies to continental drift
.
Named after him are:
, then of Amsterdam
. He grew up in a protected environment. In 1910 he graduated in civil engineering in Delft
. The same year he started working for the Dutch gravitational survey. In 1915 he wrote his dissertation on the defects of the gravimeters used at that time.
Vening Meinesz then designed a new gravimeter, which the KNMI (Royal Dutch Meteorological Institute) built. The apparatus has two pendula
of the same size hanging in a frame but moving in opposite phases. With mirrors and lightbeams the difference in amplitude of the two pendula is captured on a film. Vening Meinesz had discovered that horizontal accelerations (as by waves on a boat) had no influence on the difference in amplitude between the two pendula. The recorded difference then is the amplitude of a theoretical, undisturbed pendulum. Now it became possible to measure gravity more accurately. Vening Meinesz started with measuring gravity all over the Netherlands, for which a network of 51 monitoring stations was created. This became a success, which encouraged him to do measurements at sea. A perfected gravimeter, hanging in a 'swing', was designed. The experiment was successful.
Now measuring gravity at sea had become possible. Between 1923 and 1929 the tall (over 2 metres) Vening Meinesz embarked in small submarines for some uncomfortable expeditions. His goal was to establish the exact shape of the geoid
and the Earth. When his expedition with the submarine Hr. Ms. K XVIII was made into a movie in 1935, Vening Meinesz became a hero of the Dutch cinema public. Besides, his research was in the international scientific spotlight. In 1927 he become a parttime professor in geodesy, cartography
and geophysics at Utrecht University
, and in 1937 he became professor at the Delft University of Technology
as well. He was awarded the Howard N. Potts Medal in 1936.
In World War II
, Vening Meinesz was involved in the Dutch resistance. After the war he could take up his tasks as a professor again. From 1945 to 1951 he was the director of the KNMI. He retired in 1957.
, B.G. Escher
and Ph.H. Kuenen
, the results were published in 1948. An important result was the discovery of elongated belts of negative gravity anomalies
along the oceanic trench
es. The mean gravity force appeared to be the same on land and at sea, which was in agreement with the principle of isostasy
. Vening Meinesz was especially intrigued by the oceanic trenches. The coexisitence of active volcanism
, large negative gravity anomalies and the sudden difference in terrain elevation could only be explained by assuming the Earth's crust
was somehow pushed together at these places. As a geophysicist, he was prejudiced that the crust was too rigid to deform at that scale in such a way. His discoveries could be explained only with the development of the theory of plate tectonics
in the '50s.
The Hague
The Hague is the capital city of the province of South Holland in the Netherlands. With a population of 500,000 inhabitants , it is the third largest city of the Netherlands, after Amsterdam and Rotterdam...
July 30, 1887 - Amersfoort
Amersfoort
Amersfoort is a municipality and the second largest city of the province of Utrecht in central Netherlands. The city is growing quickly but has a well-preserved and protected medieval centre. Amersfoort is one of the largest railway junctions in the country, because of its location on two of the...
August 10, 1966) was a Dutch geophysicist
Geophysics
Geophysics is the physics of the Earth and its environment in space; also the study of the Earth using quantitative physical methods. The term geophysics sometimes refers only to the geological applications: Earth's shape; its gravitational and magnetic fields; its internal structure and...
and geodesist
Geodesy
Geodesy , also named geodetics, a branch of earth sciences, is the scientific discipline that deals with the measurement and representation of the Earth, including its gravitational field, in a three-dimensional time-varying space. Geodesists also study geodynamical phenomena such as crustal...
. He is known for his invention of a precise method for measuring gravity. Thanks to his invention, it became possible to measure gravity at sea, which led him to the discovery of gravity anomalies
Gravity anomaly
A gravity anomaly is the difference between the observed acceleration of Earth's gravity and a value predicted from a model.-Geodesy and geophysics:...
above the ocean floor. He later attributed these anomalies to continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...
.
Named after him are:
- a gravimeterGravimeterA gravimeter or gravitometer is an instrument used in gravimetry for measuring the local gravitational field of the Earth. A gravimeter is a type of accelerometer, specialized for measuring the constant downward acceleration of gravity, which varies by about 0.5% over the surface of the Earth...
, an apparatus to measure gravity - a mathematical function used in geodesy
- a medal of the European Geophysical Society/European Geosciences UnionEuropean Geosciences UnionThe European Geosciences Union is an interdisciplinary non-profit learned society open to individuals who are professionally engaged in or associated with geosciences, planetary and space sciences, and related studies.The mission statement of the EGU is "Dedicated to the pursuit of excellence in...
- a research school at Utrecht UniversityUtrecht UniversityUtrecht University is a university in Utrecht, Netherlands. It is one of the oldest universities in the Netherlands and one of the largest in Europe. Established March 26, 1636, it had an enrollment of 29,082 students in 2008, and employed 8,614 faculty and staff, 570 of which are full professors....
- The crater Vening MeineszVening Meinesz (crater)Vening Meinesz is a lunar crater on the far side of the Moon. The northern inner wall of this crater lies along the lunar equator. To the north of this formation is the larger crater Mandel'shtam, and slightly farther to the south is the larger Keeler...
on the MoonMoonThe Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
.
Biography
Vening Meinesz' father, Sjoerd Anne Meinesz, was mayor, first of RotterdamRotterdam
Rotterdam is the second-largest city in the Netherlands and one of the largest ports in the world. Starting as a dam on the Rotte river, Rotterdam has grown into a major international commercial centre...
, then of Amsterdam
Amsterdam
Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...
. He grew up in a protected environment. In 1910 he graduated in civil engineering in Delft
Delft
Delft is a city and municipality in the province of South Holland , the Netherlands. It is located between Rotterdam and The Hague....
. The same year he started working for the Dutch gravitational survey. In 1915 he wrote his dissertation on the defects of the gravimeters used at that time.
Vening Meinesz then designed a new gravimeter, which the KNMI (Royal Dutch Meteorological Institute) built. The apparatus has two pendula
Pendulum
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position...
of the same size hanging in a frame but moving in opposite phases. With mirrors and lightbeams the difference in amplitude of the two pendula is captured on a film. Vening Meinesz had discovered that horizontal accelerations (as by waves on a boat) had no influence on the difference in amplitude between the two pendula. The recorded difference then is the amplitude of a theoretical, undisturbed pendulum. Now it became possible to measure gravity more accurately. Vening Meinesz started with measuring gravity all over the Netherlands, for which a network of 51 monitoring stations was created. This became a success, which encouraged him to do measurements at sea. A perfected gravimeter, hanging in a 'swing', was designed. The experiment was successful.
Now measuring gravity at sea had become possible. Between 1923 and 1929 the tall (over 2 metres) Vening Meinesz embarked in small submarines for some uncomfortable expeditions. His goal was to establish the exact shape of the geoid
Geoid
The geoid is that equipotential surface which would coincide exactly with the mean ocean surface of the Earth, if the oceans were in equilibrium, at rest , and extended through the continents . According to C.F...
and the Earth. When his expedition with the submarine Hr. Ms. K XVIII was made into a movie in 1935, Vening Meinesz became a hero of the Dutch cinema public. Besides, his research was in the international scientific spotlight. In 1927 he become a parttime professor in geodesy, cartography
Cartography
Cartography is the study and practice of making maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively.The fundamental problems of traditional cartography are to:*Set the map's...
and geophysics at Utrecht University
Utrecht University
Utrecht University is a university in Utrecht, Netherlands. It is one of the oldest universities in the Netherlands and one of the largest in Europe. Established March 26, 1636, it had an enrollment of 29,082 students in 2008, and employed 8,614 faculty and staff, 570 of which are full professors....
, and in 1937 he became professor at the Delft University of Technology
Delft University of Technology
Delft University of Technology , also known as TU Delft, is the largest and oldest Dutch public technical university, located in Delft, Netherlands...
as well. He was awarded the Howard N. Potts Medal in 1936.
In World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, Vening Meinesz was involved in the Dutch resistance. After the war he could take up his tasks as a professor again. From 1945 to 1951 he was the director of the KNMI. He retired in 1957.
Research and Discoveries
The vast amounts of data that his expeditions yielded were analyzed and discussed together with other leading Dutch Earth scientists of the time J.H.F. UmbgroveJohannes Herman Frederik Umbgrove
Johannes Herman Frederik Umbgrove , called in short Jan Umbgrove, was a Dutch geologist and Earth scientist.Umbgrove studied geology at Leiden University, he finished his studies in 1926...
, B.G. Escher
Berend George Escher
Berend George Escher was a Dutch geologist.Escher had a broad interest, but his research was mainly on crystallography, mineralogy and volcanology. He was a pioneer in experimental geology. He was a half-brother of the artist M.C. Escher, and had some influence on his work due to his knowledge of...
and Ph.H. Kuenen
Philip Henry Kuenen
Philip Henry Kuenen was a Dutch geologist.Kuenen spent his earliest youth in Scotland, where his father was professor in physics. He studied geology at Leiden University, where he was a pupil of K. Martin and B.G. Escher. He finished his studies in 1925 and then became assistant to Escher...
, the results were published in 1948. An important result was the discovery of elongated belts of negative gravity anomalies
Gravity anomaly
A gravity anomaly is the difference between the observed acceleration of Earth's gravity and a value predicted from a model.-Geodesy and geophysics:...
along the oceanic trench
Oceanic trench
The oceanic trenches are hemispheric-scale long but narrow topographic depressions of the sea floor. They are also the deepest parts of the ocean floor....
es. The mean gravity force appeared to be the same on land and at sea, which was in agreement with the principle of isostasy
Isostasy
Isostasy is a term used in geology to refer to the state of gravitational equilibrium between the earth's lithosphere and asthenosphere such that the tectonic plates "float" at an elevation which depends on their thickness and density. This concept is invoked to explain how different topographic...
. Vening Meinesz was especially intrigued by the oceanic trenches. The coexisitence of active volcanism
Volcanism
Volcanism is the phenomenon connected with volcanoes and volcanic activity. It includes all phenomena resulting from and causing magma within the crust or mantle of a planet to rise through the crust and form volcanic rocks on the surface....
, large negative gravity anomalies and the sudden difference in terrain elevation could only be explained by assuming the Earth's crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...
was somehow pushed together at these places. As a geophysicist, he was prejudiced that the crust was too rigid to deform at that scale in such a way. His discoveries could be explained only with the development of the theory of plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
in the '50s.