Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Only above-water microbes play a role in cave development

03.09.2015

Only the microbes located above the water's surface contribute to the development of hydrogen-sulfide-rich caves, suggests an international team of researchers. Since 2004, researchers have been studying the Frasassi cave system, an actively developing limestone cave system located 1500 feet underground in central Italy.

Limestone caves can form when solid limestone dissolves after coming in contact with certain types of acids. The resulting void is the cave system.


This image shows two researchers working in a cave.

Credit: Macalady, Penn State

"We knew from previous research that microbes do play a role in cave development," said Jennifer Macalady, associate professor of geosciences, Penn State and co-author of a paper published today (Sept. 2) in Chemical Geology. "What we were trying to assess was the extent of that contribution, which would help us understand how caves all over the world, as well as on other worlds, form."

In hydrogen-sulfide-rich caves, microbes "eat" the hydrogen sulfide through a process known as aerobic respiration, Macalady said. The byproduct of this process is the creation of sulfuric acid, which has the potential to dissolve limestone and contribute to cave growth.

"The main goal of our study was to investigate what happened to hydrogen sulfide in the cave, because when the microbes use hydrogen sulfide for energy, this, along with oxygen, leads to the production of sulfuric acid," said Macalady.

The researchers measured oxygen levels and the amount of chemicals degassing -- changing from liquid to gas state -- throughout several parts of the cave system. The Frasassi system has cave pathways that formed 10,000 to 100,000 years ago as well as currently actively forming cave pathways, allowing the researchers to compare their measurements and identify the factors contributing to active development.

"What we found is that in certain conditions, the hydrogen sulfide in the water escapes as a gas into the air above the water instead of being 'eaten' by microbes below the water surface," said Macalady. "As a result, the underwater microbes only partially burned hydrogen sulfide. Instead of creating a byproduct of sulfuric acid, they created pure sulfur as a byproduct, which is not corrosive to limestone."

In contrast, the microbes above the water's surface completely "ate" the hydrogen sulfide. This process results in the creation of sulfuric acid, which dissolves limestone and contributes to cave growth.

Macalady says that the results would apply to all limestone caves that are rich in hydrogen sulfide, which includes more well-known caves such as Carlsbad Caverns and Lechuguilla Cave in New Mexico and Kap-Kutan Cave in Turkmenistan.

###

Co-authors on the findings include Daniel Jones, former Penn State graduate student now at the University of Minnesota; Lubos Polerecky, Max Planck Institute for Marine Microbiology and Utrecht University; Sandro Galdenzi; and Brian Dempsey, Penn State Department of Civil and Environmental Engineering.

The National Science Foundation, NASA Astrobiology Institute and the Max-Planck Society funded this work.

Media Contact

A'ndrea Elyse Messer
aem1@psu.edu
814-865-9481

 @penn_state

http://live.psu.edu 

A'ndrea Elyse Messer | EurekAlert!

More articles from Earth Sciences:

nachricht Atmospheric scientists reveal the effect of sea-ice loss on Arctic warming
11.03.2019 | Institute of Atmospheric Physics, Chinese Academy of Sciences

nachricht Sensing shakes
11.03.2019 | University of Tokyo

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

Im Focus: A thermo-sensor for magnetic bits

New concept for energy-efficient data processing technology

Scientists of the Department of Physics at the University of Hamburg, Germany, detected the magnetic states of atoms on a surface using only heat. The...

Im Focus: The moiré patterns of three layers change the electronic properties of graphene

Combining an atomically thin graphene and a boron nitride layer at a slightly rotated angle changes their electrical properties. Physicists at the University of Basel have now shown for the first time the combination with a third layer can result in new material properties also in a three-layer sandwich of carbon and boron nitride. This significantly increases the number of potential synthetic materials, report the researchers in the scientific journal Nano Letters.

Last year, researchers in the US caused a big stir when they showed that rotating two stacked graphene layers by a “magical” angle of 1.1 degrees turns...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

How heavy elements come about in the universe

18.03.2019 | Physics and Astronomy

Robot arms with the flexibility of an elephant’s trunk

18.03.2019 | Power and Electrical Engineering

Microbes can grow on nitric oxide (NO)

18.03.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>