However, for the 3.5, 3, 2, and 0 Ma models, the eastern BC values were calculated by interpolation between the 4.5 Ma model hydraulic head values and present-day hydraulic head values obtained from
potentiometric surface maps of the Wolfcampian and Mississippian (Figures 9 and 11; [7]); see [h.sub.E] = [h.sub.i] arrows in Figure 13.
"We observed that over time the way groundwater moved and where it was present changed significantly," said USGS hydrologist Rachel Powell, lead author of the report Estimated 2012 groundwater
potentiometric surface and drawdown from predevelopment to 2012 in the Santa Fe Group aquifer system in the Albuquerque metropolitan area, central New Mexico.
The
potentiometric surface of the Voronka groundwater body had lowered 20-50 m by 1990 due to intensive water abstraction (Fig.
Potentiometric surface analysis and water loss studies indicate that significant spring recharge comes directly from the lower Blanco River (Ogden et al.
As a result of the intensive use, in the 1990s the
potentiometric surface sank deeper than 50 m below sea level in the area of Kohtla-Jarve-Johvi, and an extensive drawdown cone was formed.
An analog exists for confined aquifers and is called the
potentiometric surface (or piezometric surface).
The
potentiometric surface was determined by plotting measurements taken at each of the piezometers.
The Analytic Element Method (AEM) of groundwater modeling was used to generate a steady state
potentiometric surface map of the water-table aquifer in the Wadena area of Central Minnesota.
This equation is governed by the Dupuit Assumptions: hydraulic gradient is the slope of the water table or
potentiometric surface; hydraulic gradient is invariant with depth; and flow lines are horizontal.
Groundwater is mostly confined and its
potentiometric surface lies at a depth of 3-8 m from the ground surface.
These results are very similar to an earlier 1985 USGS study of computed
potentiometric surface for the area.