Slope-Channel Complexes at Guadalupe Canyon, Upper Brushy Canyon Formation, Texas, USA
C Rossen, R. T Beaubouef, 2008. "Slope-Channel Complexes at Guadalupe Canyon, Upper Brushy Canyon Formation, Texas, USA", Atlas of Deep-Water Outcrops, Tor H. Nilsen, Roger D. Shew, Gary S. Steffens, Joseph R. J. Studlick
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Upper Brushy Canyon outcrops at Guadalupe Canyon (north outcrop belt) provide a spectacular, strike view of vertically stacked, large, erosional channels that are incised into thick successions of laminated siltstones and thin-bedded sandstones (Zelt and Rossen, 1995; Beaubouef et al., 1999). The channel-bounding master erosion surfaces are low-aspect-ratio (<20:1) features, 15–30 m (50–100 ft) deep and up to 400 m (1300 ft) wide. The channels trend southeast–east, indicating flow toward the basin at a high angle to the basin-margin trend. channel fills are variable and include: 1) thick packages of thin-bedded siltstones and sandy turbidites that drape channel margins, 2) tabular, nonamalgamated, thick-bedded, massive, fine-grained sandstones that change facies into thin-bedded turbidites at channel margins (dominant type), and 3) erosionally based, amalgamated, thick-bedded, fusulinid-rich sandstones. channel margins are geometrically complex and characterized by: 1) stacked erosion surfaces, 2) inclined packages of thin-bedded, sandy turbidites and siltstones that drape channel margins, and 3) remnant (or truncated) channelform sandstones. At the base of the section, a siltstone-draped truncation surface with irregular geometry is a possible slump scar that appears to have influenced the location of younger channels.
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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