Unknown water in the earth’s interior

University of Münster is involved in the new "Center for Molecular Water Science

Water is not only essential for life, it is also a fascinating and complex molecule that forms the basis of all life on earth. In the new "Centre for Molecular Water Science", a European research network, scientists are investigating the molecular properties of water and its compounds. Stephan Klemme and Carmen Sanchez Valle from the Institute of Mineralogy at the University of Münster are part of the consortium. In particular, they want to understand water in extreme environments in the Earth’s interior. "We know water in its everyday form as a liquid, gas or ice. In nature, however, water occurs in many other phases. Under extreme pressure, such as that found in the Earth’s interior, water can become what are known as supercritical fluids," explains Stephan Klemme. "These special forms of water dissolve metal ions, which makes them particularly interesting for geological and mineralogical research."

One of the scientists’ aims is to investigate the solubility of valuable metals such as gold or rare earths in supercritical aqueous fluids under the high pressure and temperature conditions of the Earth’s interior. Rare earths are indispensable for modern technologies; they are used in smartphones, batteries for electric cars and wind turbines. "We want to understand how and where these deposits are formed in the Earth’s interior," emphasizes Stephan Klemme. According to the EU, the availability of many of these metals is "critical", especially in view of China’s dominance on the global market, as a study by the German Mineral Resources Agency states.

The researchers use innovative high-pressure equipment that they develop themselves and have built in the Institute of Mineralogy’s in-house workshop. "We compress water together with metals, oxides and other minerals in special diamond stamp cells and typically heat this mixture up to 800 degrees Celsius. This is how we create supercritical fluids. These samples are then examined using high-energy X-rays to find out which metals and other chemical elements can be dissolved and transported under these conditions," Carmen Sanchez Valle explains the procedure. "We recreate the conditions of nature in the laboratory as realistically as possible, because we can’t drill that far into the ground to investigate the deep interior of the earth."

Researching the molecular properties of water and its role in geological processes not only helps scientists to better understand how deposits are formed, but also to develop predictive models for the formation of economically relevant raw materials. Carmen Sanchez Valle categorizes basic research in this area: "This knowledge is crucial to securing the resources of critical elements for the future."

The "Center for Molecular Water Science":

The "Center for Molecular Water Science" (CMWS) is a European research network for molecular water research. More than 60 research institutions and universities are currently involved in the CMWS, including more than 55 from Europe. The researchers come from the fields of physics, geosciences, chemistry, biology, medicine, nanotechnology and engineering. The center of the CMWS initiative is the German Electron Synchrotron DESY in Hamburg. With world-leading large-scale facilities, interdisciplinary centers and specialized campus partners, the location offers an ideal environment for developing the CMWS into an international beacon of molecular water research. The initiative defines five strategic research areas: (1) fundamental properties of water, (2) climate, astronomical and geosciences, (3) energy research and technology, (4) real-time chemical dynamics and (5) molecular biosciences. These five areas form the basis for the overarching research of the CMWS and interlink basic research with application-oriented research.

Author: Kathrin Kottke

This article is from the Unizeitung wissen