Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Million year old groundwater in Maryland water supply

19.06.2012
A portion of the groundwater in the upper Patapsco aquifer underlying Maryland is over a million years old. A new study suggests that this ancient groundwater, a vital source of freshwater supplies for the region east of Washington, D.C. and Baltimore, was recharged over periods of time much greater than human timescales.

"Understanding the average age of groundwater allows scientists to estimate at what rate water is re-entering the aquifer to replace the water we are currently extracting for human use," explained USGS Director Marcia McNutt. "This is the first step in designing sustainable practices of aquifer management that take into account the added challenges of sea level rise and increased human demand for quality water supplies."

This new study from the USGS, the Maryland Geological Survey (MGS) and the Maryland Department of the Environment (MDE) documents for the first time the occurrence of groundwater that is more than one million years old in a major water-supply aquifer along the Atlantic Coast. The oldest groundwater was found in the deepest parts of the aquifer, but groundwater even in shallower parts of the aquifer is tens to hundreds of thousands years old.

Groundwater age indicates the length of time that a sample of water has been in the ground since infiltrating from the land surface. This study reveals that modern pumping in southern Maryland west of the Chesapeake Bay and on the Eastern Shore is tapping groundwater resources that have accumulated in the aquifer over multiple cycles of climate change and are not quickly recharging.

The analysis shows that water flowed from the land surface into the deep aquifer during cooler periods in earth's history, when glaciers covered much of the northeastern U.S. and sea level was about 125 meters lower than it is today. During warmer periods in earth's history, such as in modern times, higher sea levels slow recharge of fresh water to the aquifer, due to a lower gradient between the recharge and discharge areas.

Modern-day pumping rates have lowered water pressures and changed water chemistry, affecting the aquifer's ability to provide freshwater for drinking and other uses. Concerns over saltwater intrusion in some areas have led water managers to increasingly move groundwater production from shallower aquifers to the deeper upper Patapsco aquifer, which has caused groundwater levels to decline.

The findings are being used to help understand the patterns and rates of groundwater movement in the aquifers of the Coastal Plain. Such information will be used by the Maryland Department of the Environment to ensure that the management and use of the State's groundwater resources are being carried out to protect its long-term sustainability. The findings bring into focus that current users are withdrawing groundwater that was recharged eons ago and accentuate the need to review current water-supply management strategies and develop new tools and models to protect this valuable resource for the future.

There are relatively few aquifers in the world in which million-year-old groundwater has been documented, including the Nubian aquifer in the Sahara Desert, Canada's Alberta Basin, and the Great Artesian Basin in Australia

Aquifer sustainability is one of several priority topics currently being addressed by the USGS Groundwater Resources Program (http://water.usgs.gov/ogw/gwrp/), the USGS National Research Program (http://water.usgs.gov/nrp/), and the USGS Cooperative Water Program (http://water.usgs.gov/coop/).

More information about the study is available online (http://www.springerlink.com/content/j08u34jh46r632v4/) and in Hydrogeology Journal in an article titled, "Old groundwater in parts of the upper Patapsco aquifer, Atlantic Coastal Plain, Maryland, USA: evidence from radiocarbon, chlorine-36 and helium-4," by L. N. Plummer, J. R. Eggleston, D. C. Andreasen, J. P. Raffensperger, A. G. Hunt, and G. C. Casile. If you would like a copy of the report, contact Kara Capelli at kcapelli@usgs.gov.

USGS provides science for a changing world. Visit USGS.gov, and follow us on Twitter @USGS and our other social media channels. Subscribe to our news releases via e-mail, RSS or Twitter.

Kara Capelli | EurekAlert!
Further information:
http://www.usgs.gov

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>