Discussion of “Permian—Triassic vertebrate footprints from South Africa: Ichnotaxonomy,producers and biostratigraphy through two major faunal crises” by Marchetti,L., Klein,H., Buchwitz,M., Ronchi,A., Smith,R.M.H., DeKlerk,W.J., Sciscio,L., and Groenewald,G.H. (2019)

A newly devised tripartite subdivision of the Karoo Basin, South Africa, is based on a number of vertebrate-trackways spanning the Middle Permian (Wordian/Capitanian) to Lower Triassic (reportedly Induan) rocks of the Beaufort Formation. The youngest Footprint Assemblage (FA III) is reported to occur in the lowermost Triassic rocks of the Palingkloof Member. One collection site from which seven trackways are reported, Bethel farm, is a classic South African locality where some authors place the end-Permian extinction event and, coincidentally, the vertebrate-based terrestrial Permian—Triassic Boundary. Published GPS coordinates for the Bethel farm site, though, indicate that these trackways originate from exposures of the Burgersdorp Formation near the town of Aliwal North. Outcrops here are assigned to the Cynognathus Assemblage Zone, and indicate a Middle Triassic age assignment. In addition, we caution the use of any small temporally or spatially restricted dataset, which is of severely limited utility, in making broad generalizations about paleoenvironmental or paleoecological interpretations.     

Background radiation in the Albuquerque,New Mexico,U.S.A., area

Background radiation levels in the Albuquerque, New Mexico, area are elevated when compared to much of the United States. Soil K, U, and Th are somewhat elevated compared to average values in this country and generate roughly 60 mrem per year to the average resident. Cosmic ray contribution, due to the mean elevation of 5,200 ft above sea level, is 80 mrem/yr—well over the average for the United States. Thirty percent of the homes in Albuquerque contain indoor radon levels over the EPA action level of 4 pCi/ compared to 10–12 percent of homes for the entire United States. Indoor radon contributes about 100–300 mrem/yr. Food, beverages, and x-ray doses are assumed at an average-equivalent for the United States and locally yield 96 mrem/yr. Total contributions from other minor sources (color TV, coal, weapons fallout, etc.) are under 10 mrem/yr. Thus total background radiation received by Albuquerque residents is about 330–530 mrem/yr, well in excess of the rest of the United States. The spread in mrem values is due to variations in the contribution from indoor radon.Douglas G. Brookins, Professor of Geology and former Chairman of the Department, 1976–1979, passed away unexpectedly on April 30, 1991. He was a man of passion, intellect, and conviction. He left us at the peak of his productive career, but he leaves behind a legacy of exceptional accomplishments and contributions to his friends, family, students, and profession. He was a member of the Faculty Senate at the time of his death and had served two previous terms in 1984 and 1986.Doug's academic accomplishments were of world class, beginning with an AB degree, Summa Cum Laude, from U.C. Berkeley in 1958 and a PhD from MIT in 1963. He came to UNM as a full professor in 1971, having previously served at Kansas State University, and built a first class program in isotope geochemistry. He wrote five books and had a sixth in progress, edited several others, and authored or coauthored approximately 500 technical papers, book chapters, and reports.—Bruce M. Thomson and Wolfgang E. Elston, University of New Mexico.