I had the honor of meeting Hans Renz in 1946 in Caracas, where Hollis Hedberg had asked him to come to discuss a possible position with Mene Grande Oil Company. He was a tall man with a ramrod straight posture, thinning brown hair, and a basso guttural voice. He spoke excellent English, Spanish, and French, although German was his native language. Hans transferred to Caracas when I was leaving for the States, but we maintained a professional relationship and a personal friendship that lasted until his death.
Hans Hermann Renz was born on May 9, 1910, in Ludwigsburg, southwestern Germany. His father was a tailor who worked for a large manufacturing firm there. He had an older brother, Willy, and a twin sister, Gretel. In 1927, the family was transferred to Bern, Switzerland, but Hans remained in Germany until completion of his high school degree in 1928. He rejoined the family, but later returned to Germany where he attended a few semesters at the Stuttgart Polytechnic School. There he became very interested in the natural sciences, geology in particular.
In 1930, he enrolled at the University of Bern, majoring in geology under Professor Paul Arbenz. In 1934, he graduated, magna cum laude, with a Ph.D. in geology and paleontology. His thesis, his first paper, was published in the Eclogae Geologicae Helvetiae in 1935. It concerned the stratigraphy and paleontology of the Mytilus Shale in the Swiss Prealps. Hans remained at the university for two additional years, doing post-graduate work in stratigraphy and paleontology. During that time, he was an assistant to Professor Arbenz, and during the summers of 1934 and 1935, he worked with Professor Maurice Gignoux from the University of Grenoble.
In December 1936, Hans married a young lady from Switzerland named Martha Renz—no relation! Shortly afterward, he left, alone, for a position as micropaleontologist with the Trinidad Leaseholds Ltd. geological laboratory in Pointe-à-Pierre, Trinidad, under Hans Kugler. Six months later, Martha joined him. In 1939, he was promoted to Chief Stratigrapher in charge of the laboratory. That same year, Martha had a son, Hansueli, and in 1942, a daughter, Marianne. Both were born in Pointe-à-Pierre.
In addition to his regular duties, Hans published a number of papers on the stratigraphy and paleontology of Trinidad, Venezuela, and California.
In 1947, he moved to Caracas, Venezuela, as Director of Mene Grande Oil Company’s Stratigraphic Laboratory. He held that position until 1963. This was a very prolific period of his life. Besides directing the laboratory and being involved in Mene Grande exploration decisions, he was a member of the Gulf Oil Geological Committee. He assisted at the inaugural session of the International Sub-commission on Stratigraphic Classification (ISSC) at the International Geological Congress in Algiers in 1952, and was a member of the Sub-commission until 1985. He also published a number of papers on paleontology and Venezuelan geology. Among these are several papers co-authored with J.A. Cushman. His most outstanding paper is the Geological Society of America Memoir 32 on the “Stratigraphy and Fauna of the Agua Salada Group, State of Falcón, Venezuela,” published in 1948.
From 1963 to 1969, with the impending Venezuelan nationalization of oil companies, Hans worked as an exploration advisor on loan to Gulf’s Eastern Hemisphere Division headquartered in London. There he came in contact with European, African, and Middle Eastern exploration problems.
In 1969, Hans retired from Mene Grande and moved back to Switzerland. However, in 1972, he was asked to consult for Gulf Oil Corp., and he moved to Coral Gables, Florida. His studies covered exploration problems in the Caribbean, eastern Canada, Taiwan, Sulawesi, northern Sumatra, and northeastern Colombia.
This activity lasted until 1981, when he returned to Switzerland, and his forty-five year involvement with the petroleum industry came to an end.
Hans Renz belonged to many American, Venezuelan, and European scientific organizations. He had been a member of the American Association of Petroleum Geologists since 1941 and a Fellow of the Geological Society of America since 1949. Besides numerous private reports, Hans authored or co-authored 35 publications.
He was part of a group of brilliant Swiss biostratigraphers, which included Hans Bolli and Paul Brönnimann, gathered by a relatively small oil company, Trinidad Leaseholds Ltd. In those days, micropaleontology was still a young science used mostly for the purpose of well correlation. Hans was one of the earliest workers to stress the importance of planktonic species for regional correlations because of their relative independence from local environment. He stated in 1948 (GSA Memoir 32) “The composition of a foraminiferal assemblage at any given point in the sea depends on depth, temperature, salinity, aeration, light, configuration of sea floor, etc. … However if there are pelagic species of known time significance present in otherwise heterotropic faunas, a correlation will be possible regardless of the faunal facies. A pertinent example is Globorotalia foshi.” Today, pelagic microfauna are widely used in chronostratigraphy. In 1969, Hans was co editor with Paul Brönnimann of the Proceedings of the First International Conference on Planktonic Microfossils held in Geneva in 1967.
During his entire life, Hans had a deep concern about stratigraphic nomenclature. With H.D. Hedberg and H.G. Schenck, he was one of the early proponents of a clear separation between chronologic, chronostratigraphic, and lithologenetic units. He made great contributions to the understanding of northern South American stratigraphy.
Although Hans always enjoyed Swiss fondue, hiking, swimming, tennis, and photography, his real hobby was geology—he was a geologist’s geologist.
In 1993, after nearly fifty-eight years of marriage, his beloved Martha died after a long illness, and he passed away ten years later, on January 10, 2003.
Hans is survived by his son, Hansueli, who, with his family, lives in Switzerland, and by his daughter, Marianne, who resides in the United States.
SELECTED BIBLIOGRAPHY OF HANS H. RENZ
1935 Zur Stratigraphie und Paläontologie der Mytilus-Schichten im östlichen Teil der Préalpes Romandes: Eclogae Geologicae Helvetiae, v. 28, no. 1, p. 141–247
1936 Pflanzenführender Keuper in der Breccien-Decke des Simmentals: Eclogae GeologicaeHelvetiae, v. 29, no. 1, p. 257–259
—— Neuen Cephalopoden aus der Oberen Kreide vom Rio Grande del Norte (Mexico und Texas): Mém. Soc. Pal. Suisse, v. 57, p. 1–16.
1940 Wissenschaftliche Ergebnisse der Neiderländischen Expeditionen in der Karakorum und die Gebeite in den Jahren 1922, 1925, 1929/30 und 1935. v. III, Fasc. 1, Paläontologie: Leiden, E.J. Brill, p. 4–88, 119–293, Plates I to XVI, one sketch map.
1941 (with Cushman, J.A.) New Oligocene-Miocene Foraminifera from Venezuela: Cushman Laboratory for Foraminaferal Research, Contributions, v. 17, pt. 1, p. 1–27.
1942 Stratigraphy of Northern South America, Trinidad and Barbados. Eighth American Scientific Congress Proceedings, Washington, D.C., v. IV, Geological Sciences, p. 513–571.
—— (with Cushman, J.A.) Eocene, Midway, Foraminifera from Soldado Rock, Trinidad: Cushman Laboratory for Foraminaferal Research, Contributions, v. 18, pt. 1, p. 1–14.
1946 (with Cushman, J.A.) The Foraminiferal Fauna of the Lizard Springs Formation, Trinidad, British West Indies. Cushman Laboratory for Foraminaferal Research, Contributions, Special Publication no. 18, p. 1–48.
1947 (with Cushman, J.A.) Further Notes on the Cretaceous Foraminifera of Trinidad. Cushman Laboratory for Foraminaferal Research, Contributions, v. 23, pt. 2, p. 31–51.
—— (with Cushman, J.A.) The Foraminiferal Fauna of the Oligocene Ste. Croix Formation in Trinidad, B. W. I. Cushman Laboratory for Foraminaferal Research, Special Publication no. 22, p. 1–46.
1948 Stratigraphy and Fauna of the Agua Salada Group, State of Falcón, Venezuela: Geological Society of America Memoir 32, 219 p.
—— (with Cushman, J.A.) Eocene Foraminifera of the Eocene Navet and Hospital Hill Formations of Trinidad: B.W.I. Cushman Laboratory for Foraminaferal Research, Special Publication no. 24, p. 1–42.
1949 (with Probst, D.A., and Otamendi, P.) Sedimentación Aplicada: Boletín de la Asociación Venezolana de Geología, Minería y Petróleo, Tomo I, no. 1, p. 33–53.
1951 (with Mencher, E., Fichter, H.J., Renz, H.H., Wallis, W.E., Patterson, J.M., and Robie, R.H.) National Petroleum Convention, Caracas, Venezuela, September 9–18, 1951: The Ministry of Mines & Hydrocarbons: Geological Reviews, p. 50–53, 56–70.
1953 (with Mencher, E., Fichter, H.J., Renz, H.H., Wallis, W.E., Patterson, J.M., and Robie, R.H.) Geology of Venezuela and its Oil Fields. American Association of Petroleum Geology Bulletin, v. 37, no. 4, p. 690–777.
1955 Some Upper Cretaceous and Lower Tertiary Foraminifera from Aragua and Guárico, Venezuela: Micropaleontology, v. I, no. 1, p. 52–71.
1956 Contributor to: Léxico Estratigráfico de Venezuela: Ministerio de Minas e Hidrocarburos, Dirección de Geología: Boletín de Geología, Publicación Especial, no. 1. Published also by the Congrès Géologique International, Mexico, 1956. Commission de Stratigraphie, v. V, Fascicule 3, p. 1–741.
—— Review of the “Geological Structure of the South American Cordillera,” by Heinrich Gerth: American Association of Petroleum Geology Bulletin, v. 40, no. 4, p. 769–773.
—— (with Young, G.A., Bellizzia, A., Johnson, F.W., Robie, R.H., and Mas Vall, J.) Geología de las Cuencas Sedimentarias de Venezuela y de sus Campos Petrolíferos: Ministerio de Minas e Hidrocarburos, Boletín de Geología, Publicación Especial no. 2. Also: XXº Congreso Geológico Internacional, 1956 —Pt. D. Symposio sobre Yacimientos de Petróleo y Gas, Tomo IV, América del Sur y Antillas: México, p. 161–322.
1957 Stratigraphy and Geological History of Eastern Venezuela: Geologische Rundschau, v. 45, Heft 5, p. 728–759.
—— (with Bermudez, P.J.) Determination of Smaller Foraminifera from the Gatuncillo (p. 15–19) and Bohio (p. 26–27) Formations, in Woodring, W.P., ed., Geology and Paleontology of Canal Zone and Adjoining Parts of Panamá: Geological Survey Professional Paper 306-A.
1958 (with Alberding, H., Dallmus, K.F., Patterson, J.M., Robie, R.H., Weisbord, N.E., and Mas Vall, J.) The Eastern Venezuelan Basin Habitat of Oil. Symposium: Tulsa, Oklahoma, American Association of Petroleum Geologists, p. 551–600.
1961 Correlation of Geologic Formations in Venezuela: Asociación Venezolana de Geología, Minería y Petróleo, Boletín Informativo, v. 4, no. 6, p. 199–203.
1962 Stratigraphy and Paleontology of the Type Section of the Santa Anita Group, and Overlying Merecure Group, Río Querecual, State of Anzoátegui, Northeastern Venezuela: Asociación Venezolana de Geología, Minería y Petróleo, Boletín Informativo, v. 5, no. 4, p. 89–108.
1963 (with Alberding, H., Dallmus, K.F., Patterson, J.M., Robie, R.H., Weisbord, N.E., and Mas Vall, J.) La Cuenca Oriental de Venezuela: Aspectos de la Industria Petrolera en Venezuela: Primer Congreso Venezolano de Petróleo, Caracas, 1962, p. 100–189.
1969 (with Brönnimann, P.) Editor, Proceedings of the First International Conference on Planktonic Microfossils, Geneva, 1967, Leiden, E.J. Brill