Is there a geomorphic expression of interbasin groundwater flow in watersheds? Interactions between interbasin groundwater flow, springs, streams, and geomorphology

Abstract

Interbasin groundwater flow (IGF) can play a significant role in the generation and geochemical evolution of streamflow. However, it is exceedingly difficult to identify IGF and to determine the location and quantity of water that is exchanged between watersheds. How does IGF affect landscape/watershed geomorphic evolution? Can geomorphic metrics be used to identify the presence of IGF? We examine these questions in two adjacent sedimentary watersheds in northern New Mexico using a combination of geomorphic/landscape metrics, springflow residence times, and spatial geochemical patterns. IGF is expressed geomorphically in the landscape placement of springs and flow direction and shape of stream channels. Springs emerge preferentially on one side of stream valleys where landscape incision has intercepted IGF flow paths. Stream channels grow toward the IGF source and show little bifurcation. In addition, radiocarbon residence times of springs decrease and the geochemical composition of springs changes as the connection to IGF is lost.

Hydrologic functioning of the deep critical zone and contributions to streamflow in a high‐elevation catchment: Testing of multiple conceptual models

“…If this model is accepted and the hypothesized shallow groundwater endmember is ignored, then we implicitly overlooked the non‐conservative behaviour of Si, and we have also ignored the stream water compositions that do not fall on the EM1–EM2–EM3 projected space (Figure c). As Si is a major weathering product for most sites (White, ; White & Blum, ), and it is a useful tool for understanding subsurface chemical denudation processes (Frisbee, Tolley, & Wilson, ; Frisbee, Phillips, White, Campbell, & Liu, ; Frisbee et al, ), ignoring the non‐conservative behaviour of Si or stream water chemistry observations (especially winter season samples) is problematic. Therefore, the model CM2A is abandoned, and other models with the same mixing space dimension are considered next.…”

Are catchments leaky?

“…If a portion of the streamflow comes from other catchments through groundwater import, then weathering rates would be overestimated, disproportionally so for the same reason. These are vividly demonstrated in Figure 11 by Frisbee et al (2016) and Figure 12 by Genereux et al (2009). Further confusion can be introduced if the hydrologic models erroneously placed the groundwater import or export term into the catchment storage term.…”

“…Yellow and blue lines mark cross‐sections shown to the right. (Reprinted with permission from Frisbee et al (). Wiley 2016)…”

“…As mentioned earlier, Stewart‐Maddox et al () and Frisbee et al () integrated data on geology, hydrology (e.g., gaining vs. losing streams, clustering of springs), geomorphology (asymmetry in hillslope and channel profiles), and geochemistry (trends in 87 Sr/ 86 Sr, inverse geochemical modeling of groundwater evolution). In doing so, they “bookended” the intercatchment groundwater transfer, showing its termination at the second catchment in a three‐catchment catena (Figure ).…”

Drainage from the Critical Zone: Lithologic Controls on the Persistence and Spatial Extent of Wetted Channels during the Summer Dry Season

“…During base flow, headwater streams act as surficial expressions of groundwater conditions, providing observable spatiotemporal information of groundwater storage within catchments (e.g., Bencala et al, 2011;Biswal & Nagesh Kumar, 2013;Godsey & Kirchner, 2014;Kirchner, 2009;Shaw et al, 2017;Whiting & Godsey, 2016). In rain-dominated climates, all stream flow during these dry periods must come from water stored belowground, typically in the form of slowly draining groundwater that is locally sourced from adjacent hillslopes or is derived from regional groundwater systems that may cross local hillslopes or topographic watershed divides (e.g., Broda et al, 2012Broda et al, , 2014Clark et al, 2009;Frisbee et al, 2016;Gleeson & Manning, 2008;McNamara et al, 2011;Payn et al, 2012;Sheets et al, 2015;Tague & Grant, 2004;T oth, 1963;Troch et al, 2003;Welch & Allen, 2012). The hydraulic conductivity, geometry, and volume of this storage source should impact both the persistence and distribution of wetted channels in the dry season.…”