Differences in weathering pattern, stress resistance and community structure of culturable rock-weathering bacteria between altered rocks and soils

Comparison between Salt crystallization weathering test and natural weathering in Mesozoic’s anisotropic rocks, a case study: Arakʾs Calcareous slates, Iran

Salt crystallization can severely damage anisotropic foliated rocks, therefore it is necessary to have an understanding of crystallization process. The present study was conducted to investigate the effect of salt crystallization on Arakʾs calcareous slates, as anisotropic rocks of Mesozoic. To compare salt crystallization weathering (EN 12370 norm was used up to 30 cycles) with natural weather...

Microbial populations and activities in the rhizoplane of rock-weathering desert plants. I. Root colonization and weathering of igneous rocks.

Dense layers of bacteria and fungi in the rhizoplane of three species of cactus (Pachycereus pringlei, Stenocereus thurberi, Opuntia cholla) and a wild fig tree (Ficus palmeri) growing in rocks devoid of soil were revealed by bright-field and fluorescence microscopy and field emission scanning electron microscopy. These desert plants are responsible for rock weathering in an ancient lava flow a...

Thermal stress weathering and the spalling of Antarctic rocks

Using in situ field measurements, laboratory analyses, and numerical modeling, we test the potential efficacy of thermal stress weathering in the flaking of millimeter-thick alteration rinds observed on cobbles and boulders of Ferrar Dolerite on Mullins Glacier, McMurdo Dry Valleys (MDV). In particular, we examine whether low-magnitude stresses, arising from temperature variations over time, re...

In situ and experimental evidence for acidic weathering of rocks and soils on Mars

[1] Experimental data for alteration of synthetic Martian basalts at pH = 0–1 indicate that chemical fractionations at low pH are vastly different from those observed during terrestrial weathering. Rock surface analyses from Gusev crater are well described by the relationships apparent from low-pH experimental alteration data. A model for rock surface alteration is developed, which indicates th...

Weathering and Development of Chemically Mature Soils