New world map shows the Earth´s surface 100 times more accurately

07.12.2012

What would the Earth look like if we could see beneath its surface? Researchers from the University of Hamburg/ KlimaCampus are now able to present a very accurate picture of the Earth´s crust beneath its thin surface layer. The new map depicts the characteristics of bedrock 100 times more accurately than older maps. In other words, the bedrock is examined under a microscope instead of just with a magnifying glass. Therefore, the new lithological world map offers an important database to model different processes on the Earth´s surface and to assess geohazards more precisely.

Jens Hartmann and Nils Moordorf have just published the global lithological map in the international research journal ´´Geochemistry Geophysics Geosystems´´. To do so, they not only combined 75 geological maps with more than 300 references, but also collected new data and digitalized older maps. ´´For the map, we combined the characteristics of the bedrock in different regions, like piecing together a large puzzle,´´ says Nils Moordorf. ´´We standardized the nomenclature of the rock types globally and eliminated contradictions as well as blind spots”. Blind spots occurred especially at shared borders as they were often researched in different ways.

The new map consists of 16 different general types of rock and numerous subclasses, which can be combined in more than 400 different ways. It is easier to spot geohazards when the distribution of rock types is known. For example, lime stone dissolves comparatively quickly and thus forms very impressive cave systems. However, when these caves collapse, the result can be large holes on the surface. The map shows areas prone to collapses caused by chemical and physical weathering.

At the same time, the map offers important data for climate research. For instance, the weathering of certain rocks reduces the concentration of the greenhouse gas CO2 in the atmosphere. ´´We are interested in discovering areas where a lot of rock weathering occurs. We want to find out how much CO2 is bound in water in those cases,´´ says Moosdorf. Furthermore, the database can also be used to predict the long-term availability of phosphor and silicium. Both are important nutrients for the ecosystem.

Colleagues from around the world can use the work of the researchers from Hamburg as a data source. For example, the database is already being used by the Canadian McGill University to compose a global map of groundwater permeability. Furthermore, the King´s College in London uses the data for hydrogeologic models. Last but not least, the Max-Planck-Institute for Meteorology at the KlimaCampus is using the database to calculate the carbon balance of future ecosystems - with the help of the global lithological map.

The original article is available at:
http://www.agu.org/pubs/crossref/2012/2012GC004370.shtml

An animation of the world map is available at:
http://www.vis.klimacampus.de/2270.html?&L=1



For further questions, please contact:

Prof. Jens Hartmann/ Dr. Nils Moosdorf
Universität Hamburg, KlimaCampus
Tel: (040) 42838 6683
E-Mail: jens.hartmann@zmaw.de/ nils.moosdorf@zmaw.de

Franziska Neigenfind
Universität Hamburg, KlimaCampus
Öffentlichkeitsarbeit
Tel: (040) 42838 7590
E-Mail: franziska.neigenfind@zmaw.de