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Kuenen, Philip Henry

KUENEN, PHILIP HENRY

(b. Dundee, Scotland, 22 July 1902; d. Leiden, Netherlands, 17 December 1976), sedimentology, marine geology, experimental geology.

Kuenen grew up in a bilingual household and came from a strong intellectual and scientific background. He was the third of the five children of Johannes Petrus Kuenen, of Dutch heritage, and Dora Wicksteed, who was English. Kuenen’s father was professor of physics at Dundee (1896–1907) and then at Leiden until his death (1922); Kuenen’s brother Donald Johan became an eminent zoologist at Leiden University.

As a child, Kuenen was a collector: his first acquisition was a human appendix in a jar, and he began collecting rocks at the age of eight. He received virtually all of his schooling in Leiden and was awarded an undergraduate degree in geology in 1922 and a Ph.D. in 1925. As an undergraduate Kuenen had begun research on Tertiary fossils from Timor under the direction of the paleontologist Karl Martin, whom he greatly admired. Taxonomic work did not suit him, however, and he was relieved to turn it over to another student when Martin retired in 1922, and to study under B. G. Escher, a structural geologist. Escher set up an experimental laboratory upon his arrival in 1922, and his approach to solving geological problems had a lasting impact on Kuenen.

Kuenen’s graduate research was on the porphyry district of Lugano, in the Alps, but he soon diverged from this area of study. He remained at Leiden from 1926 to 1934 as a geological assistant, and during this time began conduction divers geological experiments. Escher recommended Kuenen as geologist for the Snellius expedition (1929–1930) to the Netherlands Indies (specifically, to the Moluccas) and its associated deep basins and troughs. The emphasis of this expedition was on oceanography, biology, and geology, particularly on collecting data with new instrumentation, such as continuousrecording echo sounding. During this same period and at various other times in the 1920’s, the eminent Dutch geophysicist Felix Andries Vening Meinesz was conducting gravity surveys in the Netherlands Indies. These surveys were to have a major impact on tectonic concepts, and Kuenen modeled some of the results in an experiment.

In 1934 Kuenen took a position as undergraduate lecturer and curator of collections at Groningen, where the professorship of geology had been abolished after the retirement of Bonnema in 1932. There were very few students, an arrangement that suited Kuenen, who could therefore devote most of his time to research. He was promoted to reader in 1939 and to professor in 1946 (later backward to 1943); the latter promotion was held up by the German-influenced administration. ostensibly because of Kuenen’s English heritage, though his political views were probably a factor. Kuenen served as an observer in the Dutch air force and was wounded during the German takeover (May 1940); later he was briefly imprisoned by the Germans, and his collection of photographs was confiscated (it was never returned).

When Leiden University was closed early in the was, geology students came to Groningen to study, which at first pleased Kuenen but soon reconfirmed his preference for research rather than teaching and supervision. He tried to discourage undergraduates from pursuing geology as a career, commonly expressing the opining that there was no future in geology, and he would not take graduate students until they had completed all their graduate coursework (and a first graduate degree) elsewhere. Kuenen did take teaching seriously. however, and considered it his duty to educate. He was a thorough but dry lecturer, and students who came to know him learned to recognize his very subtle humor. He helped to write two textbooks and also wrote nontechnical books and articles. He produced at least one paper on teaching technique, encouraging the use of stereo paris of photographys; Kuenen sometimes used stereo projections in class, and the students wore special glasses. He was an excellent photographer and used stereo pairs in some publications or made them available to readers.

Kuenen was professor of geology and director of the Geological Institute at the University of Groningen until his retirement in 1972; he briefly held the positions of dean of the faculty (1951–1952) and rector magnificus (1960). Although Kuenen’s eminence had resulted in the revival and maintenance of a geological program at Groningen, he did not develop a strong school or a political base in an academic system that was strongly political; the small scale of the program at Groningen was in part a result of Kuenen’s reluctance to take on students, Neverthelevess, some very prominent young sedimentologists came to do their doctorates at Groningen or to conduct postdoctoral research and others held state-supported positions in the institute. Around 1970 Kuenen spent considerable time and effort fighting abolition of the geology program at Groningen and elsewhere in the Netherlands; the stress constributed to his second nervous breakdown.

On 2 April 1932 Kuenen married charlotte susanne Wilhelmine Pijzel, who became a strong helpmate and counterbalance to Kuenen’s rather sober demeanor. They had three daughters and a son. Kuenen’s daily life was quite regimented-he bicycled to work, bicycled home for lunch, bicycled back to work. Kuenen did not own a car, nor did he drive. But he traveled extensively to international meetings, usually with his wife, and he typically took advantage of these trips to visit field localities. The death of his wife in 1967 was a great shockto Kuenen, probably causing the first of two nervous breakdowns. Thisloss, combined with administrative problems, caused a dramatic drop in Kuenen’s scientific productivity. He died in 1976 during surgery for an aneurysm.

Kuenen’s influence was in three fields: experimental geology, encouraged by his mentor, Escher; marine geology, stimulated by his experience on the Snellius expedition; and the combination of these two with field geology (in collaboration with others) to generate a model for the deposition of coarse sediments in the deep sea by the action of turbidity currents. On the latter topic he wrote some fifty papers (about a quarter of his published work), nearly all of which he wrote alone. For his scientific contributions, particularly his work on turbidity currents and turbidites, Kuenen received six major geological medals (Waterschoot van der Gracht, Penrose, wollaston. Shepard, Dumont, and steinmann). three honorary doctorates (Dublin, Cracow, and Exeter), and numerous distinguished lectureships, honorary memberships, and other awards.

Over a ten-year period beginning in 1928, Kuenen published a remarkable series of papers in experimental geology (almost all in Leidsche geologische mededeelingen), Principally relating to structural and tectonic problems. His first major paper (1928) concerned the effects of wind action on pebbles; he reversed the flow of a vacuum cleaner and sandblasted easily erodible articfical pebbles of chalky consistency, in order to speed up the processes. This work confirmed laws of wind faceting formulated by Albert Heim (Escher’s former supervisor). He followed this project with an experimental study written with Escher (1929) on the genesis and structure of folds in salt domes; other related work included a paper with L. U. de Sitter on folding (1938) and a paper on ptygmatic folding (1938), a subject to which Kuenen later returned (1968). Spurred by results from the Snellius expedition and Vening Meinesz’s gravity data, Kuenen also performed experiments on the genesis of volcanic cones (1934) and of negative gravity anomalies by downbucking of the crust due to horizontal compressive stresses (1936).

As a preface to the latter paper, Kuenen quoted Chester R. Longwell: “The field of tectonics is no place for a prim individual who likes everything orderly and settled and has a horror of loses ends.” It was not long after this paper that Kuenen left the field of structural geology and tectonics—partly because he considered it to be “messy” and probably partly because he was being overshadowed by L. U. de Sitter and Particularly by J. H. F. Umbgrove.

In a review of experimental geology (1965), KUenen concluded that structural geology and tectonics (“endogenic geology”) were stubborn subjects, and that the most promising area of experimental geology was that of external or surface Processes. He stated that transportation by ice, water, and wind could be tested, qualitatively and quantitatively, and wind fouls be tested, qualitatively and flows, and turbidity currents offered a wide field for the experimental approach. Kuenen’s first experimental work, mentioned above, was on surface processes, and his first experiment on turbidity currents was conducted in 1936 and 1937; he continued experimenting with turbidity currents and related phenomena for the rest of his active career. In addition. in the 1950’s he began a protracted series of experiments on abrasion of pebbles and sand by various processes. published in a series of six papers (1955–1964).

Experiments conducted by Kuenen ranged from sophisticated to simple; he had a knack for clever experimental design on a low budget, and he enjoyed tinkering and woodworking—as a hobby he constructed detailed models of sailing ships. Clearly he was led into experimental geology by Escher, but several other factors motivated him. His up-bringing and his superior intellect would have inclined him to test critically ideas or hypotheses generated in his or others’studies; he also had strong physical intuition but professed no mathematical ability. (For the time and in his field of sedimentology, Kuenen was considered to be quantitative.) Experimental work suited his life-style as well as his scientific approach; although he traveled extensively, he was not particularly attract to fieldwork.

Kuenen became a proselytizer for experimental geology. publishing several versions of papers on its value while acknowledging that experimental technique did not seem to suit most geologists, compared with physicists or chemists. He discussed the pitfalls of experiments, such as incorrect scaling or producingsomething that looked right by processes improbable in nature; but he extolled the productive functions of geological experiments: “to illustrative, clarify, test, or exclude suggested explanations or imagined processes, to provide new concepts, to furnish data, to allow inspectionof processes [that is, processes that otherwise could not be observed], [and] to allow study of simplified natural processes” (“The Value of Experiments in Geology,” p.32).

Marine Geology. Kuenen’s career as marine geologist started with his participation in the Snellius expedition. As had been true of Charles Darwin and James Dwight Dana, this endeavor matured Kuenen, deepened and broadened his experience in a very short time, and provided a fertile ground for the generation of ideas to be tested (and ultimately to be published). Kuenen was a very careful observer, and his original reports include geological mapping and description of islands, discussion of bathymetrical results, discussion of geological significance of gravity data, and geology of coral reefs; Gerda A. Neeb analyzed the sediment samples taken by Kuenen on the expedition.

Oceanic coral reefs had been a focus of geological study at least since Darwin’s time, particularly because they were indicators of sea level; yet some were at present dead and submerged, whereas others had survived, apparently by accumulating to great thickness. Theories for the controls of coral–reef life, growth, and death included tectonic subsidence and eustatic (worldwide) sea–level change, particularly during the late Cenozoic glacial ages; temperature changes during glacial ages were also incorporated. Darwin and Dana considered some aspects of this problem in the nineteenth century, and twentieth–century contributors to the discussions included William Morris Davis, Reginald Aldworth Daly, and Umbgrove. Kuenen (1933, 1947) favored a combination of controls on reef growth and pointed out that coral in the Moluccas had survived sealevel changes and ocean-temperature variation in the late Cenozoic.

Other work that emanated from Kuenen’s Snellius experience included discussions of eustatic changes of sea level, calculations of the total mass of sediments in the deep sea and on Earth, studies of several volcanogenic phenomena, and consideration of submarine currents. Three books were generated during this time, two of them popular works; Kuenen’s “diary” of the expedition, Kruistochten over de Indische diepzeebekkens (1941), and De kringloop van het water (1948; revised and translated into English in 1955), a discussion of the presence and action of water in its various forms on earth. The third was a textbook, Marine Geology (1950).

The field of marine geology grew explosively following World War II, and Kuenen’s text was influential, though quickly eclipsed by rapid progress in the field. He never revised it. In his book Kuenen tried to summarize the state of the entire field. but the text also presents many of his own studies and contains many fertile ideas. At about the same time (1948), Francis P. Shepard published Submarine Geology, which went through two revisions and ultimately supplanted Kuenen’s work. Whereas Shepard continued to practice marine geology—to direct scientific cruises—Kuenen never again participated in an oceanographic expedition. However, he kept abreast of developments in marine geology and several times gave papers in which he emphasized the importance to geologists of marine geology and the study of modern processes. He Contributed ideas, for example, to the studies of H. Postma and of Kuenen’s colleague L. M. J. U. van Straaten concerning Sediment transport and deposition on modern Dutch tidal flats (1958). Kuenen firmly believed that experiments and studies of the modern were critical tests of historical geological reconstructions.

Submarine Canyons and Turbidity Currents . The development of continuous echo sounding in the 1930’s led to the discovery and detailed mapping of many submarine topographic features. some of the most spectacular of which were submarine canyons. Study of these steep-walled, valleys deep–sea launched the careers of Kuenen and Shepard, but in very different ways. Shepard made a career of the detailed field study of canyons—their topography, the composition of their walls and floors, the currents that flowed within them, and related features. Impressed with their steepness, he originally postulated that they were eroded subaerially when the continents were much more elevated, and by observation he spent much of his career testing and revising this hypothesis.

Kuenen never personally studied a submarine canyon; he entered the field when he read a paper by Daly (1936) postulating that submarine canyons were eroded by the action of subaqueous. sedimentladen density currents (subsequently named “turbidity currents” by Douglas Johnson, 1938). These currents had been observed in lakes and reservoirs, and Daly believed they had been very active at the edge of the continental shelf during glacioeustatic lowstands of sea level, when waves would generate great turbulence there. By his own admission, Kuenen did not take this paper seriously until Vening Meinesz said he thought it presented a viable hypothesis. Kuenen was then spurred to conduct experiments on the generation, nature, and erosive capability of turbidity currents. He concluded that they could erode submarine canyons, siding with Daly in a debate that has not yet been entirely resolved. At that time, both Daly and Kuenen were considering low–density, mud–laden currents. Kuenen’s first two papers on this subject, published in 1937 and 1938, did not generate much interest, acceptance, or rebuttal outside of those directly involved.

During World War II, Kuenen continued to publish papers based on his Snellius experience, as well as on a variety of topics that did not require fieldwork. At this time he apparently also was working on his books, as well as a text on earth history with Isaak M. van der Vlerk (the principal author), all of them published in the late 1940’s. In 1947 Kuenen published a major summary and discussion of his ideas about coral atolls and submarine canyons; in regard to the latter, he restated his position but put more emphasis on the action of submarine slumps in addition to turbidity currents.

Also at this time Kuenen renewed his experiments, now concentrating on high–density turbidity currents generated in a flume and in a ditch in his yard. He produced a film of these experiments, and presented the results and conclusions at the International Geological Congress at London in 1948. He postulated that submarine slumps and mudflows could transport very coarse sediments out of canyons, and that they could generate or evolve into highdensity turbidity currents, transporting sediments coarser that silt(that is, sand) to the deep–sea floor. Although it is clear that previous workers had published some of these ideas, it is widely agreed that Kuenen’s paper and film of 1948 started a revolution in the interpretation of graded beds of sand in the geological record.

Attending the meeting was C. I. Migliorini, who in 1944 had suggested that coarse–grained graded beds in Italy were deep–water deposits of submarine landslides and associated muddy currents. In the discussion following Kuenen’s presentation, he suggested that Kuenen’s high–density turbidity currents were the mechanism that transported coarse sediments and deposited these graded beds. Kuenen had not considered the deposits until this time— he was more concerned with erosion of submarine canyons. Migliorini took Kuenen to the Apennines, and they collaborated on a paper, “Turbidity Currents as a Cause of Graded Bedding” (1950). The paper, combining experimental results and field data, was very well received, helped in particular by a simultaneously published favorable review by Francis J. Pettijohn, one of the most influential sedimentary geologists of the era.

Also present at the meeting was Ian Campbell. He was familiar with the studies of Manley L. Natland (1933), whose paleoecological analysis of foraminifera in the Cenozoic Ventura Basin in California indicated to him that not only sands but also conglomerates had been deposited in deep water. His ideas had been met with rejection and even ridicule. Upon hearing of Kuenen’s paper and as chairman of the Research Committee of the Society of Economic Paleontologists and Mineralogists (SEPM), Natland organized a symposium at the 1950 SEPM annual meeting in Chicago, inviting Kuenen to attend and to visit him in the Ventura Basin; this visit resulted in a collaborative paper presented at the symposium. During his visit, Kuenen also traveled around the United States, lecturing and showing his film. By the time (or shortly after) the symposium proceedings were published (1951), most concerned sedimentary geologists had accepted that graded beds were the products of turbidity currents (Kuenen and Migliorini, 1950), and that these graded beds of coarse sediments (sand and coarser)were deposited in up to thousands of meters of water(Natland and Kuenen, 1951).

Therevision in interpretation of coarse-grained, graded beds caused the reinterpretation of numerous sedimentary basins. Kuenen and his students, coworkers, and others went on to refine the interpretation of sedimentary structures generated by turbidity currents and associated processes. The importance of paleocurrent indicators in these sediments was recognized, and new paleogeographic reconstructions of various basins were generated. Kuenen continued to publish numerous papers on aspects of these problems, including results of fieldwork and of newly designed experiments. He was particularly excited to learn more of coarse–grained sediment samples from deep–sea cores, especially as reported by Maurice Ewing, Bruce C. Heezen, and others from Lamont Geological Observatory in New York. He also followed their work and contributed his own to calculation of turbidity–current velocities from submarine cable breaks; it was later shown that some of these breaks were caused by slumps.

Kuenen is considered by many to be the first modern, process–oriented sedimentary geologist, principally for his work on turbidity currents, which integrated marine geology, experiment, and geological fieldwork, Roger G. Walker (1973, p. 3)argued that’ the [turbidity current]theory…represents the only true revolution in thought in this century about clastic rocks, ’ Kuenen’s other experimental work, in particular his studies of sedimentary structures and textures, generated significant results: none of Kuenen’s students became experimentalists, however, to carry on the tradition. Kuenen was a meticulous observer and a critical thinker who constantly questioned the validity of geological interpretations. A supremely intelligent individual, he could be merciless to those who were not so critical in their thinking; if asked incisive questions, however, he was very helpful. Kuenen could be gracious and witty when the occasion arose, and exhibited a sharp sense of humor. Although at times, especially in later life, Kuenen expressed insecurity about his eminence in sedimentology, it is clear that he was a giant in his field. Many prominent sedimentologists were influenced by him personally, as well as by his papers.

BIBLIOGRAPHY

1. Original Works. No bibiography has been published; Kuenen’s curriculum vitae lists 211 publications.

Kuenen’s monographs include Geology of Coral Reefs: The “snellius”Expedition, V, pt. 2 (Leiden, 1933); Geological Interpretation of the Bathymetrical Results, The snellius Expendition, V, pt. 1 (Leiden, 1935); Kruistochten over de Indische diepzeebekkens (The Hague, 1941); De Kringloop van het water (The Hague, 1948); Marine Geology (New York, 1950); and Realms of water (new york, 1955). In addition he contributed to Geheimschrift der aarde (utrecht, 1948; 6th ed., 1951), Isaak M. van der Vlerk the principal author;and wrote the introductory section to Bottom Samples:The “snellius” Expedition, V, pt. 3 (Leiden, 1943), Gerda Neeb author of the body of the report.

Kuenen’s papers include “Experiments on the Formation of Windworn Pebbles,” in Leidsche geologische mededeelingen, 3 (1928), 17–38; “Experiments in connection with salt Domes,” ibid., 3 (1929), 151–182, with B. G. Escher; “Experiments on the Formation of Volcanic Cones,” ibid., 6 (1934), 99–118; “The Negative Anomalies in the East Indies (with Experiments),” ibid., 8 (1936), 169–214 “Expermients Investigation with Daly’s Hypothesis on the Formation of submaric Canyons,” ibid. 8 (1937), 327–351; “Experimental Investigation into the Mechanism of folding,” ibid., 10 (1938), 217–239, with L. U. de sitter; “Observations and Experiments on Ptygmatic Folding,” in C. R. Soc. géol. Finl., 12 (1938), 11–28; “Density Currents in connection with the problem of Submarine Canyons,” in Geological Magazine, 75 (1938), 241–249; “Geological Calculations Concerning the total Mass of Sediments in the Earth,” in American journal of science, 239 (1941), 161–190; “Pitted Pebbles,” in Leidsche geologische mededeelingen, 13 (1942), 189– 201; “TwoProblems of Marine Geology: Atolls and Canyons,” in Verhandelingen der Koninklijke Nederlandsche akademie van wetenschappen, afdeeling natuurkunde, sec. 2, 43 no. 3 (1947), 1–69; “The Formation of Beach Cusps,” in Journal of Geology, 56 , (1948), 34–40 “Turbidity Currents of High Density,” in Report of the 18th International Geological Congress, pt. 8 (London, 1950), 44–52; “Turbidity Currents as a Cause of Graded Bedding,” in Journal of Geology, 58 (1950), 91–127, with C. I. Migliorini.

“Sedimentary History of the Ventura Basin, California, and the Action of Turbidity Currents,” in J. L. Hough, ed., Turbidity Currents and the Transportation of Coarse Sediments to Deep Water, Society of Economic Paleontologists and Mineralogists Special Publication no. 2 (1951), 76–107, with Manley L. Natland; “Significant Features of Graded Bedding,” in Bulletin of the American Association of Petroleum Geologists, 37 (1953), 1044–1066; “Origin and Classification of Submarine Canyons,” in Bulletin of the Geologica; Society of America. 64 (1953), 1293–1314; “Sea Level and Crustal Warping,” in Arie poldervaart, ed., Crust of the Earth. Geological Society of America special Paper no. 62 (1955), 193–204; “Experimental Abrasion of Pebbles 2. Rolling by Current,” in Journal of Geology, 64 (1956), 336–368; “Tidal Action as a Cause of Clay Accumulation.” in Journal of Sedimentary Petrology. 28 (1958), 406–413, with L. M. J. U. van Straaten: “Sand,” in Scientific American, 202 no. 4 (1960), 94–110; “Deep-Sea Sands and Ancient Turbidites,” in A. H. Bouma and A. Brouwer, eds., Turbidites (Amsterdam, 1964), 3’33; “Emperimental Abrasion, 6, Surf Action,” in Sedimentology, 3 (1964), 29–43; “Value of Experiments in Geology,” in Geologie en mijnbouw, 44 (1965), 22–36; “Experimental Turbidite Lamination in a Circular Flume,” in Journal of Geologuy, 74 (1966), 523–545; “Emplacement of Flysch-Type Sand Beds,” in Sedimentaology, 9 (1967), 203–243; “Origin of Ptygmatic Features,” in Tectonoplihsics, 6 (1968), 143’158; “Tentative Data on Flow Resistance in Resistance in Suspension Currents,” in Geologie en mijnbouw, 50 (1971), 429–442; and “Continental Shelf” and “Continetal Slope,” in Encyclopaedia Britannica, 15th ed. (1974), III, 585.

II. Secondary Literature. Only short memorial notes have been published: A. Brouwer, in De Leidse geoloog, 40 (1977), 7–12, a newsletter of Leiden geology students (in Dutch); Francis P. Shepard, in Geological Society of America. Memorials, 8 (1978); L. M. J. U. van Straaten, in Geologie en mijnbouw. 56 (1977), 1–3 (in Dutch); and E. K. W. (E. K.Walton), in Geological Society of London Annual Report for 1977, 35–36.

Kuenen and F. L. Humbert published a 700–entry “bibliography of Turbidity Currents and Turbidites,” in A. H. Bouma and A. Brouwer, eds., Turbidites (Amsterdam, 1964), 222–246. Roger G. Walker has written a history of turbidity-current and turbidity conscepts: “Mopping Up the Turbidite Mess,” in Robert N. Ginsburg, ed., Evolving Concepts in Sedimentology (Baltimore, 1973), 1–37.

This biography was preparde from the content of Kuenen’s papers, from memorials and medal citations, and from interviews with and questionnaires from Kuenen’s students, colleagues, and contemporaires, including Tj. van Andel, G. J. Boekschoten, J. R. Boersma, A. H. Bouma, A. Brouwer, R. H. Dott, Jr., G. de V. Klein, G. V. Middleton, G. Postma, H. G. Reading, J. E. Sanders, L. M. J. U. van Straaten, J. Terwindt, and R. G. Walker. I was provided with copies of correspondence between some of these people and Kuenen, as well as correspondence between Kuenen and Shepard from the Scripps Institution of Oceanography archives. Kuenen’s daughter Madeline Dommering-Kuenen compiled information for me from the Kuenen family.

Joanne Bourgeois

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Kuenen, Philip Henry

Kuenen, Philip Henry (1902–72) A Dutch geologist and one of the founders of modern sedimentology, Kuenen's participation in the Snellius deep-sea expedition to the Moluccas (1929–30) directed his attention to marine geology. One of the very few experimental geologists, he demonstrated the efficacy of high-density turbidity currents in transporting sand to deep-sea environments. In 1950 Kuenen, together with the Italian geologist C. I. Migliorini, interpreted the graded sandstone beds of ancient flysch sequences as turbidites. The study of their sedimentary structures has contributed much to palaeogeography. His most widely known book in the English language is the early classic on Marine Geology (1950).

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"Kuenen, Philip Henry." A Dictionary of Earth Sciences. . Retrieved August 21, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/kuenen-philip-henry