Valley and Ridge

Valleys and ridges corresponding to cases 1 through 4 can lead to a minimum or maximum, respectively, but not for cases 8 through 11. Do you see why ... 

Figure 17a. Relationship between median wet deposition ofN (N03 + NH4+) and median surface-water N (N03 + NH4+) concentrations for physiograph-ical districts within the National Stream Survey that have minimal agricultural activity. [Subregions are Poconos-C at skills (ID), Southern Blue Ridge Province (2As), Valley and Ridge Province (2Bn), Northern Appalachians (2Cn), Ozarks—Ouachitas (2D), Southern Appalachians (2X), Piedmont (3A), mid-Atlantic Coastal Plain (3B), and Florida (3C)]. (Panel a is reproduced with permission from reference 96. Copyright 1991 American Geophysical Union.)...

Erickson, P. A. and Harbor, D. J., 1998, Bringing down Floyd incision by the James River in the valley and ridge of Virginia, Geol Soc Am Abstr Programs 30 no. 7 142. 

Evans, M. A., and Battles, D. A., 1999, Fluid inclusion and stable isotope analyses of veins from the central Appalachian Valley and Ridge province Implications for regional synorogenic hydrologic structure and fluid migration Geological Society of America Bulletin, v. Ill, no. 12, p. 1841-1860. 

Angle, J. P., 1969j The reproductive cycle of the northern ravine salaman-PlQthodon richmondi richmondi, in the Valley and Ridge Province of Pennsylvania and Maryland, J. Wash. Acad. Sci., 59 192. 

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