A Complete Middle-to-inner Basin-floor-fan Cycle, Mount Messenger Formation, Tongaporutu, New Zealand
G. H. Browne, P. R. King, M. J. Arnot, K. Helle, 2008. "A Complete Middle-to-inner Basin-floor-fan Cycle, Mount Messenger Formation, Tongaporutu, New Zealand", Atlas of Deep-Water Outcrops, Tor H. Nilsen, Roger D. Shew, Gary S. Steffens, Joseph R. J. Studlick
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This outcrop begins at the Tongaporutu River estuary car park, where a sharp contact between thick-bedded sandstones and underlying slumped siltstones marks the basal sequence boundary of a fining-upwards cycle approximately 100 m (328 ft) thick. The cycle extends along the south bank of the river and for 800 m (2625 ft) along the beach to the south. The non-erosive or mildly erosive base and sheetlike morphology of the interval exposed at the beach and in surrounding hills indicate deposition on the basin floor. Further, the dominance of thick-bedded sands and lack of large-scale internal erosional features implies a middle-fan setting. The vertical stacking pattern reflects changes in relative base-level or autocyclic lobe switching, rather than channel fill. Micropaleontological dating suggests a cycle duration of ∼50 k.y. and very high sedimentation rates of approximately 500 cm (1.6 ft) k.y., equivalent to fifth-order cycle periodicity.
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Tor H. Nilsen, a red-haired Scandinavian who stood more than six feet tall, died October 9, 2005, at his San Carlos, California, home. This was after a valiant five-year fight with melanoma cancer. He was 63. His ashes were scattered at his family plot in Norway in 2006.
He was born in New York City on November 29, 1941, to Mollie Abrahamson and Nils Marius Nilsen of Mandal, Norway, and was the first of their children to be born in the United States. After graduating from Brooklyn Tech, he earned his B.S. in geology from City College of New York in 1962. While there, his prowess on the basketball court impressed a scout from the New York Knicks, but Tor went on to graduate school and earned his M.S. and Ph.D. degrees in geology from the University of Wisconsin at Madison in 1964 and 1967, respectively. His M.S. thesis was a study of Precambrian metasedimentary deposits in the Lake Superior area, and his Ph.D. thesis was a study of Devonian alluvial-fan deposits of the Old Red Sandstone in western Norway.
Dr. Nilsen’s principal expertise was in depositional systems analysis, stratigraphic analysis, and the relationships among tectonics, eustasy, and sedimentation. He began his industry career in 1967 as a research geologist with the Shell Development Company in Houston, Texas, and Ventura, California, where he worked on the tectonics and sedimentation of Tertiary shelf systems of coastal California. He subsequently spent two years with the U.S. Army Corps of Engineers as the Military