Phase contrast imaging of fall L/LL4 ordinary chondrite Bjurböle

Porosity is an essential property of chondritic meteorites and is interconnected to the evolution of their parent bodies, thermal properties, thermal metamorphism, and present state. Porosity impedes thermal paths but provides paths for shock propagation and thus is an important parameter in the characterization of these properties. Non-destructive microtomography is ideal for studying the structure of the complex, highly porous, and friable L/LL4 ordinary chondrite Bjurböle and allows quantitative 3D analysis of its porosity, texture, and pore shapes. Two imaging configurations were used to scan a 0.35 cm3 sample of Bjurböle with bulk porosity of 21.9 vol% determined using a gas pycnometer. The sample was obtained from the meteorite collection of the Finnish Museum of Natural History, University of Helsinki. Low-resolution imaging of the entire sample provided an overview of the sample material and high-resolution imaging of regions of interest within the sample bulk volume revealed the detailed porosity structure. The voxel edge lengths of low-resolution and high-resolution images are 6.5 µm and 0.65 µm, respectively.