There is plenty of room for an endolithic biosphere in basalt from mid-oceanic ridges: 3D-characterization of pore space by means of computer-tomography and image evaluation

SRISAWANG, B., MURR, A., HATZL, T., BÖHM, C., GEHLKEN, P.-L., KLENGEL, H., REITNER, J., PECKMANN, J., BÖTTCHER, M.E. (2005):
There is plenty of room for an endolithic biosphere in basalt from mid-oceanic ridges: 3D-characterization of pore space by means of computer-tomography and image evaluation

The pore space in basaltic glass containing an endolithic biosphere is characterized undestructively on a 3-dimensional base by means of computer tomography (CT) linked with image evaluation. The sample is digitally analyzed via CT on a 0.5 mm scale. The data set is put into a mask and transformed to binary data followed by an exact superimposition of the single layers. The 2-dimensional array of pixels in every layer is transformed into 3-dimensional voxel and the 3-dimensional data set is analyzed statistically. This provides information on porosity, pore volume, and distribution of pore radii. Besides this, lenght and connectivity of the pores are analyzed and the pore space is visualized 3-dimensionally in all space directions.
The method is applied to basalt samples from the Mid-Pacific ridge (ODP Leg 200) and from different localities of the Mid-Atlantic ridge. The first results show a heterogenous pattern of the pore space in the basaltic samples that appears to be linked to distribution of endolithic microorganisms.