Research Article| June 01, 2001 Strong tectonic and weak climatic control of long-term chemical weathering rates Clifford S. Riebe; Clifford S. Riebe 1Department of Earth and Planetary Science, University of California, Berkeley, California 94720-4767, USA Search for other works by this author on: GSW Google Scholar James W. Kirchner; James W. Kirchner 1Department of Earth and Planetary Science, University of California, Berkeley, California 94720-4767, USA Search for other works by this author on: GSW Google Scholar Darryl E. Granger; Darryl E. Granger 2Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907, USA Search for other works by this author on: GSW Google Scholar Robert C. Finkel Robert C. Finkel 3Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, California 94551, USA Search for other works by this author on: GSW Google Scholar Geology (2001) 29 (6): 511–514. https://doi.org/10.1130/0091-7613(2001)029<0511:STAWCC>2.0.CO;2 Article history received: 05 Oct 2000 rev-recd: 06 Feb 2001 accepted: 22 Feb 2001 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Clifford S. Riebe, James W. Kirchner, Darryl E. Granger, Robert C. Finkel; Strong tectonic and weak climatic control of long-term chemical weathering rates. Geology 2001;; 29 (6): 511–514. doi: https://doi.org/10.1130/0091-7613(2001)029<0511:STAWCC>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The relationships among climate, physical erosion, and chemical weathering have remained uncertain, because long-term chemical weathering rates have been difficult to measure. Here we show that long-term chemical weathering rates can be measured by combining physical erosion rates, inferred from cosmogenic nuclides, with dissolution losses, inferred from the rock-to-soil enrichment of insoluble elements. We used this method to measure chemical weathering rates across 22 mountainous granitic catchments that span a wide range of erosion rates and climates. Chemical weathering rates correlate strongly with physical erosion rates but only weakly with climate, implying that, by regulating erosion rates, tectonic uplift may significantly accelerate chemical weathering rates in granitic landscapes. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Research Article| September 01, 2004 Early Pleistocene incision of the San Juan River, Utah, dated with 26Al and 10Be Amy J. Wolkowinsky; Amy J. Wolkowinsky 1Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907, USA Search for other works by this author on: GSW Google Scholar Darryl E. Granger Darryl E. Granger 1Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Amy J. Wolkowinsky 1Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907, USA Darryl E. Granger 1Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana 47907, USA Publisher: Geological Society of America Received: 06 Feb 2004 Revision Received: 30 Apr 2004 Accepted: 04 May 2004 First Online: 03 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2004) 32 (9): 749–752. https://doi.org/10.1130/G20541.1 Article history Received: 06 Feb 2004 Revision Received: 30 Apr 2004 Accepted: 04 May 2004 First Online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Amy J. Wolkowinsky, Darryl E. Granger; Early Pleistocene incision of the San Juan River, Utah, dated with 26Al and 10Be. Geology 2004;; 32 (9): 749–752. doi: https://doi.org/10.1130/G20541.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Cosmogenic 26Al and 10Be in alluvial gravel on a strath 150 m above the San Juan River, Utah, reveal a depositional age of \(1.36\ ^{{+}0.20}\ _{{-}0.15}\) Ma. This gravel is correlative with a series of terraces that grade to Glen Canyon on the Colorado River, indicating a similar age for incision there. The calculated incision rate, 110 ± 14 m/m.y., is somewhat slower than that of the Colorado River in the eastern Grand Canyon and suggests active steepening of the Colorado River. The cosmogenic nuclides also indicate rapid erosion in the sediment source area and are consistent with alluviation due to enhanced Pleistocene erosion in the San Juan Mountains. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Use of the uranium and thorium decay series in geochronology plays an important role in the discovery of radioactivity. This chapter presents examples of a variety of applications of U-series to geochronology of magmas and volcanic rocks. Analysis of samples for U-series dating involves a number of steps, with varying pathways depending on sample size and composition and the analytical precision required for the specific geochronologic application. Dating of marine carbonates was among the first applications of U-series dating to geochronology and has continued to be an important contribution to understanding sealevel changes related to climate change over geologic time and, more recently, local sea-level changes related to earthquakes. In addition, application of U-series dating to speleothems has provided an important temporal constraint on paleoclimate proxies within the speleothems, and also has provided critical temporal context for archeological and anthropological studies of artifacts or bones found in caves.
The Xujiayao-Houjiayao site in Nihewan Basin is among the most important Paleolithic sites in China for having provided a rich collection of hominin and mammalian fossils and lithic artifacts. Based on biostratigraphical correlation and exploratory results from a variety of dating methods, the site has been widely accepted as early Upper Pleistocene in time. However, more recent paleomagnetic analyses assigned a much older age of ∼500 ka (thousand years). This paper reports the application of 26Al/10Be burial dating as an independent check. Two quartz samples from a lower cultural horizon give a weighted mean age of 0.24 ± 0.05 Ma (million years, 1σ). The site is thus younger than 340 ka at 95% confidence, which is at variance with the previous paleomagnetic results. On the other hand, our result suggests an age of older than 140 ka for the site's lower cultural deposits, which is consistent with recent post-infrared infrared stimulated luminescence (pIR-IRSL) dating at 160–220 ka.
Two glacial deposits in the G esso valley ( M aritime, A lps) have been 10 Be ‐dated at 20 140±1080 (weighted mean± SD ) and 16 590±970 years, respectively, thus constraining the L ast G lacial M aximum ( LGM ) and G schnitz stadials in the southwestern part of the A lps. The LGM age is chronologically coherent with MIS 2 and synchronous with most other LGM moraines in the A lps. The G schnitz stadial also appears to be in agreement with the ages obtained from other A lpine sites and with H einrich E vent I . This suggests that the A lpine glaciers reacted simultaneously and essentially synchronously with the climate change associated with H einrich E vent 1. The E quilibrium L ine A ltitudes ( ELA s) of the LGM and G schnitz reconstructed palaeoglaciers are 1850 and 1910 m a.s.l., respectively. The ELA comparison across the A lps indicates that the palaeoclimate of the M aritime A lps during the LGM was rather different from that of other A lpine sectors. However, the similar G schnitz ELA value between the G esso valley and other sites across the mountain chain indicates that Alpine glaciers responded with the same intensity to the climate change associated with H einrich E vent I . Overall, these results suggest that the interaction between the atmospheric circulation of air masses and local A lpine orography was more complex than has previously been argued.