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2016 Birdsall-Dreiss Distinguished Lecturer
Shemin Ge is professor of hydro-
geology in the Department of
Geological Sciences at the University
of Colorado Boulder. She received her
Ph.D. from Johns Hopkins University
in 1990, subsequently worked at S.S.
Papadopulos and Associates, and
then joined the University of
Colorado in 1993. At the confluence
of subsurface fluid flow physics and
rock mechanics, Ge’s early research
examined the effects of tectonic
deformation on paleo-fluid flow
dynamics in sedimentary basins. She has since moved on to
explore interactions between groundwater and earthquakes.
2.
Ge and her students and colleagues study earthquake-induced
groundwater flow as natural experiments to reveal the hydrologic
properties of geologic systems. They also explore the mechanisms
of seismicity induced by reservoir operation and wastewater
injection.
Another thread of Ge’s research relates to groundwater
resources and surface-groundwater interactions under a changing
climate with a focus on headwater regions. She has also ventured
into fracture flow and fault zone hydrology, as well as subsurface
thermal energy transport and storage. A list of her publications
can be found at www.colorado.edu/GeolSci/faculty/ge.htm.
Ge has served the hydrogeologic and broader geoscience
communities in various capacities. She was chair of the
Hydrogeology Program Planning Group for the Ocean Drilling
Program from 1999 to 2002. She was editor for Hydrogeology
Journal and associate editor for Geofluids and the Journal of
Ground Water. She recently served a two-year term as program
director for the Hydrologic Sciences Program at the U.S. National
Science Foundation.
Interested institutions can schedule a visit via our online
request form at http://cugeology.org/ges, or by contacting Shemin
Ge at shemin.ge@colorado.edu. She will present a lecture on one
or both of the topics described below. GSA’s Hydrogeology
Division is particularly interested in including liberal arts colleges
in the itinerary. The Division pays transportation expenses, and
the host institution is expected to provide local accommodations.
1. Fluid induced earthquakes: Insights from hydrogeology and
poro-mechanics: Beginning in the 1960s, pore fluid pressure
was identified as the primary culprit for inducing earthquakes
reported near deep fluid-injection wells and newly built surface
reservoirs worldwide. As these human activities continue and
grow, induced seismicity has surged in recent decades at some
but not all sites. This increase in seismicity raises the question
of what fundamental hydrogeologic and poro-mechanics
processes and parameters make some sites more prone to
induced seismicity. This lecture will offer an overview and
physical insights of fluid induced seismicity from hydrologic
and poro-mechanics perspectives. Two contrasting case studies GSA TODAY | www.geosociety.org/gsatoday
are used to illustrate how pore fluid pressure could have played
a role in observed seismicity, one near a deep-well fluid injec-
tion in the geologically quiescent region in the central U.S., and
the other near a surface reservoir in a tectonically active region.
A high rate of fluid input emerges as an important player in
contributing to induced seismicity. The first few years of fluid
injection or reservoir impoundment is typically a critical
period when seismic hazard is elevated. While preexisting
faults dictate earthquake locations, the spatial extent of pore
pressure influence could reach tens of kilometers from fluid
injection or reservoir impoundment sites. Continued research
in this direction will not only offer a better understanding of
the hydrogeologic and seismologic processes but also help to
guide best practices in the quest for water and energy
resources in coming decades.
Groundwater dynamics in headwater regions under a
changing climate: Groundwater systems receive significant
recharge in high-altitude headwater regions. Seasonal and
longer term variations in surface temperature and precipita-
tion are expected under a changing climate, which could
substantially impact groundwater recharge and subsequently
groundwater storage and discharge to surface waters down-
stream. These headwater regions are hydrologically sensitive
to surface temperature changes due to the presence of frozen
grounds that freeze and thaw seasonally and degrading
permafrost. The freeze and thaw processes lead to changes in
subsurface hydrologic properties and dynamically impede or
invigorate groundwater flow. A key question is how seasonal
and long-term surface temperature variations impact recharge
to groundwater and its interaction with surface water. This
presentation addresses this question as it relates to ground-
water flow in headwater regions. Coupled heat transfer and
groundwater flow processes are modeled for two headwater
catchments, one in the Colorado Rocky Mountains and the
other on the Tibet Plateau. These studies illustrate that
shallow groundwater flow in summer and early fall is most
energetic as thawed ground promotes snowmelt infiltration,
invigorating the exchange between groundwater and surface
water. Under increasing temperature scenarios, groundwater
discharge to surface may experience a several-fold increase in
magnitude over the decadal scale. While projected warming
leads to increased groundwater discharge to surface waters, in
the long run, insufficient recharge upstream will make it a
challenge to sustain the discharge.
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