K-Ar Dates of Fault Rocks Along the Catalina Detachment Fault, Tanque Verde Ridge, Rincon Mountains, Arizona

K-Ar data files from the Laboratory of lsotope Geochemistry at the Department of Geosciences, University of Arizona, were transferred to the Arizona Geological Survey in about 2003. This report, originally part of a proposal to the National Science Foundation, was found in those files following Professor Damon's death in 2005. It is being made available because it contains valuable and interesting information regarding the timing of movement on the Catalina detachment fault and uplift and exhumation of the Rincon Mountains. Sample locations are known only as well as can be approximated from the map figure in the text and from location information given for two of the samples by Damon et al. (1996). Additional mapping of the area by Richard et al. (2004) allows restriction of possible sample locations to the well-mapped fault zone. The types of rock in the hanging-wall of the fault at the sample areas are specified in the text of this report, but these do not match well with the rock types mapped by Richard et al. (2004). Handwritten UTM sample coordinates in this report are only estimated positions from information in this report, from Damon et al. (1996), and from Richard et al. (2004).Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected]

K-Ar Dates of Fault Rocks Along the Catalina Detachment Fault, Tanque Verde Ridge, Rincon Mountains, Arizona

K-Ar data files from the Laboratory of lsotope Geochemistry at the Department of Geosciences, University of Arizona, were transferred to the Arizona Geological Survey in about 2003. This report, originally part of a proposal to the National Science Foundation, was found in those files following Professor Damon's death in 2005. It is being made available because it contains valuable and interesting information regarding the timing of movement on the Catalina detachment fault and uplift and exhumation of the Rincon Mountains. Sample locations are known only as well as can be approximated from the map figure in the text and from location information given for two of the samples by Damon et al. (1996). Additional mapping of the area by Richard et al. (2004) allows restriction of possible sample locations to the well-mapped fault zone. The types of rock in the hanging-wall of the fault at the sample areas are specified in the text of this report, but these do not match well with the rock types mapped by Richard et al. (2004). Handwritten UTM sample coordinates in this report are only estimated positions from information in this report, from Damon et al. (1996), and from Richard et al. (2004).Documents in the AZGS Documents Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected])

COMPILATION OF UNPUBLISHED ARIZONA K-Ar DATES FROM THE UNIVERSITY OF ARIZONA LABORATORY OF ISOTOPE GEOCHEMISTRY, 1971-1991

This compilation reports the results of 296 K-Ar analysis that were done during 1971-1991 on rock samples from throughout Arizona and, for a small number of samples, from bordering areas of adjacent states and from the Pinacate volcanic field of northwestern Sonora, Mexico. All of the reported analysis were done at the Laboratory ofIsotope Geochemistry at the Department of Geosciences, University of Arizona. Most of these dates have not been previously published. Those that have been published have not included analytical data. Some of these dates have not been released because, for various reasons, it seemed likely that they did not accurately represent rock age or cooling through the argon closure temperature. 57 pages.Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected]

Compilation of Unpublished USGS and University of Arizona K-Ar Dates of Volcanic Rocks of the San Francisco Volcanic Field, Northern Arizona

This compilation reports 174 K-Ar dates from the San Francisco Volcanic Field in northern Arizona. Of these dates, 112 are from the US Geological Survey in Menlo Park, California, and 62 are from the Laboratory of Isotope Geochemistry at the Department of Geosciences, University of Arizona. Most of these dates have not been previously published and none are in the compilation by Reynolds and others (1986). Those that have been published have not included analytical data. Some of these dates have not been released because, for various reasons, it seemed likely that they did not accurately represent rock age. Dates reported here have all been recalculated using lUGS decay and abundance constants (Table 1; Steiger and Jager, 1977; see also Dalrymple, 1979). Potassium was measured by flame photometry using a lithium internal standard. Uncertainty in potassium analysis is either sample standard deviation or 0.5%, whichever is greater. Uncertainty of date, representing one standard deviation, was calculated by the method of Cox and Dalrymple (1967) assuming a standard deviation of 0.3 % for tracer calibration.Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected]

Intercomparison of high precision C-14 measurements at the University of Arizona and the Queens University of Belfast radiocarbon laboratories

High-precision measurements were completed concurrently at the University of Arizona and the Queen's University of Belfast on blind samples of Irish oak originally measured for the 1986 radiocarbon calibration curve. Subsequent single-year Sequoindendron results were decadally averaged and compared with published results on decadal Douglas-fir samples. The results of these intercomparisons show that the Arizona high-precision results compare favorably with published values from the University of Washington, but show a systematic offset with published Belfast data

Secular variation of Delta C-14 during the Medieval Solar Maximum : A progress report

The Earth is within the Contemporaneous Solar Maximum (CSM), analogous to the Medieval Solar Maximum (MSM). If this analogy is valid, solar activity will continue to increase well into the 21st century, we have completed 75 single-ring and 10 double-ring measurements from AD 1065 to AD 1150 to obtain information about solar activity during this postulated analog to solar activity during the MSM. Delta(14)C decreases steadily during the period AD 1065 to AD 1150 but with cyclical oscillations around the decreasing trend. These oscillations can be successfully modeled by four cycles. These four frequencies are 1/52 yr(-1), 1/22 yr(-1), 1/11 yr(-1), and 1/5.5 yr, i.e., the 4th harmonic of the Suess cycle, the Hale and Schwabe cycles and the 2nd harmonic of the Schwabe cycle