3D Geological Map of the World
The Earth Geological Globe is based on the revised 3rd edition of the Geological Map of the World. As reported in GEO ExPro, Vol. 11, No. 5, the most recent printed version of this was published in 2014 by the Commission for the Geological Map of the World (CGMW). The Globe integrates data from this with state of the art geological knowledge of our planet at the end of the second decade of the new millennium and is aimed at educational and wider community use, providing a simplified geology of the continents and oceans in their entirety. It includes shaded physiography to provide a complete view of the geological setting of the earth in its most natural projection.
Integration of Geodynamic Data
In addition to chronostratigraphic and lithologic information, an extensive set of geodynamic data on the continents and in the oceans is featured, including:
The location of ‘Large Igneous Provinces’ (continental traps, ‘oceanic plateaus’) formed since the end of the Palaeozoic, with an indication of the mean age of the major volcanic episodes, which correspond to large magmatic pulses, and includes the extent of the Central Atlantic Magmatic Province;
- The Meso-Cenozoic ophiolites that underline suture zones;
- The limit of the continental shelf (< 200m water depth) and the boundary between continental and oceanic crust;
- The axes of active mid-oceanic ridges marking the boundary between two divergent lithospheric plates;
- Subduction zones formed by the convergence of two plates with associated sedimentary accretionary prisms;
- Various submarine features such as seamounts, oceanic plateaus, and hotspot tracks illustrating the progression of the plates through time.
3D Geological World Map for Teaching
The Globe is a major teaching aid that provides a clear visualisation of the main plates and sub-plates underpinning global tectonics and shows the real surfaces of the continents and oceans.
For example, the surface area of Greenland, which appears as large as Australia in the Mercator projection, is shown in the globe at its correct relative size – four times smaller.
The legend and explanatory notes in English and French are accessible via a QR code printed on the globe.
The starting point of the project was the original Geological Map of the World at 1:25 million scale, compiled by Philippe Bouysse, digitised in 2009 and successively upgraded to produce the graphic files of the 2010 and 2014 printed editions. In these versions the geodatabase consisted of three digital sets, one in the Mercator projection covering the areas between parallels 72° N and 72° S, and two others for the North and South Poles in the stereographic projection.
The GIS procedure to transform the spatial data of the 2D map into a 3D object required the merging of the three datasets and the restructuring of the geodatabase following a topological and set theory logic aimed at generating a single database using the same GCS_WGS_1984 Coordinate System. A style library was created to group all the symbols representing the graphic elements of the map (points, lines, polygons) and a STRM layer was also added to enable relief display.
This highly detailed operation was followed by the retro-projection of the geodatabase into two hemispheres. This part of the procedure required thorough geomatics and graphic work necessary to ensure precision and legibility to all vectorised symbols and texts. It also needed an optimal fit of all polygons and geodynamic features with the shaded relief at the particular projection required by the American manufacturer of the globe, the Replogle Globes Partners company.
The 3D Earth Geological Globe
The final stage involved the mechanical process of manufacturing the globe. The maps of the northern and southern hemispheres were printed onto a vinyl support by a specialised printing firm and then vacuum-formed onto plastic semi-spherical shells.
The resulting product is a 30 cm plastic globe delivered in two ready-to-assemble hemispheres together with a clear acrylic base on which the Earth Geological Globe can stand and be easily positioned since, as Earth itself, the globe is designed to be observed from all points of view.
Where Can I Find Out More Information?
For more information see the CGMW website - https://ccgm.org/en/