Geochemical Balance of a Small Watershed and Its Geomorphic Implications

Abstract

Research Article| October 01, 1970 Geochemical Balance of a Small Watershed and Its Geomorphic Implications EMERY T CLEAVES; EMERY T CLEAVES Maryland Geological Survey, Johns Hopkins University, Baltimore, Maryland 21218 Search for other works by this author on: GSW Google Scholar ANDREW E GODFREY; ANDREW E GODFREY Department of Geology, Vanderbilt University, Nashville, Tennessee 37203 Search for other works by this author on: GSW Google Scholar OWEN P BRICKER OWEN P BRICKER Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland 21218 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1970) 81 (10): 3015–3032. https://doi.org/10.1130/0016-7606(1970)81[3015:GBOASW]2.0.CO;2 Article history received: 23 Jan 1970 rev-recd: 22 May 1970 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation EMERY T CLEAVES, ANDREW E GODFREY, OWEN P BRICKER; Geochemical Balance of a Small Watershed and Its Geomorphic Implications. GSA Bulletin 1970;; 81 (10): 3015–3032. doi: https://doi.org/10.1130/0016-7606(1970)81[3015:GBOASW]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 SocietyGSA Bulletin Search Advanced Search Abstract A detailed input-output study of a small forested watershed draining the Wissahickon Formation in the Piedmont of Maryland revealed that chemical solution is five times as effective in removing material as is mechanical erosion. Solution weathering removes 16.9 tons/sq mi/yr of material compared with 3.2 tons/sq mi/yr by mechanical erosion.Plant activity during the growing season increased the concentration of silica, bicarbonate, calcium, and potassium, thus increasing total dissolved solids by one-third. Autumn leaf fall also caused a short-term increase of these ions.Rainfall does not simply dilute floodwaters as the concentration of sulfate, potassium, and calcium increases whereas silica and bicarbonate decrease in concentration during a flood cycle. Our data suggest that during the first half of a flood cycle, both the flood water and the dissolved solids in it come from an area in and immediately adjacent to the flood plain.The weathering model derived from our study suggests that on a long-term basis approximately one-half of the erosion of the Pond Branch watershed is caused by chemical solution of the silicate minerals kaolinite, vermiculite, biotite, and oligoclase. This contrasts to short-term ratio of solutional to mechanical weathering of five to one. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.