Roger D. Shew, 2008. "Sheet, Thin-bed, and Channel Architectures in the Tourelle Formation, Ste. Anne des Monts, Gaspé Peninsula, Canada", Atlas of Deep-Water Outcrops, Tor H. Nilsen, Roger D. Shew, Gary S. Steffens, Joseph R. J. Studlick
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The Lower Ordovician Tourelle Formation is well exposed near Ste. Anne des Monts on the Gaspé Peninsula (Figures 1, 2). It was deposited along the southeast margin of an elongate foredeep trough as a series of small, coalescing, sand-rich to mixed-sediment fans. Deposition occurred in a partitioned basin formed as a part of the Taconic orogeny. The deep-water deposits have been slightly metamorphosed and structurally deformed (minor faulting and up turned/vertical beds).
The outcrop is composed of >180 m (>600 ft) of stacked sandstones and shales (Figure 3). The overall net-to-gross (N/G) is 60%. Three units were studied in detail: a lower sheet sand, a middle thin-bed interval, and an upper channel. The sheet sand and channel were described as Units 4 and 5, respectively, by Hiscott and DeVries (1995). All of the outcrops studied have >275 m (>900 ft) of excellent lateral exposure at low tide.
The lower sheet sand is a layered sheet with laterally continuous beds that are bounded by mudrocks. There are amalgamated beds in the middle of the unit that increase the vertical connectivity. The N/G is 75%. The flow units are composed of fine- to coarse-grained, poorly sorted sandstones with both base- and top-missing Bouma sequences. Slurry beds (debris flows) are locally present as complete beds and/or as parts of beds. The thin beds, interpreted as interchannel deposits, have a N/G of 50%. They are composed of base-missing Bouma sequences dominated by Tc bedding. Although the ripples pinch and swell,
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Atlas of Deep-Water Outcrops
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