When disposing nuclear waste in clay formations it is expected that the most radiotoxic elements like Pu, Np or Am move only a few centimetres to meters before they decay. Only a few radionuclides are able to reach the biosphere and contribute to their long-term exposure risks, mainly anionic species like I129, Cl36, Se79 and in some cases C14 and Tc99, whatever the scenario considered. The rec...

The Opalinus Clay formation will host geological nuclear waste repositories in Switzerland. It is expected that gas pressure will build-up due to hydrogen production from steel corrosion, jeopardizing the integrity of the engineered barriers. In an in situ experiment located in the Mont Terri Underground Rock Laboratory, we demonstrate that hydrogen is consumed by microorganisms, fuelling a mic...

The area under study is located in northern Iran at 36° 47’ latitude and 50° 12' longitude. It is 15 km from southeastern Deylaman. Petrological study of the kaolin mother rock (Eocene age) under a microscope shows that the rock is vitric tuff with a rhyolitic combination containing falcated and embowed glass shards. The thickness of the layer is approximately 20 meters, formed unconformably on...

In the context of deep waste disposals, geological barrier (i.e., host rock) will be exposed to saline plumes from bituminous and alkaline concrete degradation. These chemical disturbances affect hydraulic mechanical properties clay rock by modifying its microstructure. As a result, self-sealing fractures created during excavation could affected,further affecting long-term safety repositories. ...

In the unglaciated parts of Southwestern Wisconsin, buried Terra Rossas are commonly found. These clayey, red soils are buried by loess and mainly found on ridges underlain by limestone. They have been eroded during periglacial climates. The red clay has implications for groundwater recharge as well as lateral flow through the landscape. This project focusses on a 50 km2 watershed where some 40...

Clay-sulfate rocks are often encountered in engineering projects such as underground construction and waste repositories. The unique combination of clay swelling and chemical transformation of anhydrite into gypsum results in a swelling behavior that cannot be explained using conventional rock mechanics. The goals of this study are: 1) to investigate the strength characteristics of reconstitute...

With the current developments in imaging/computational techniques and resources, computational rock physics has been emerging as a new field of study. Properties of rocks are examined by carrying out extensive numerical simulations on rocks that have been digitized using high-resolution X-ray CT scans. The ultimate goal of computational rock physics is to supplement the traditional laboratory m...

The thermodynamic properties of clay minerals, which control the stability of these minerals in solution, are still a matter of debate in spite of recent advances (Gailhanou et al., submitted). This is especially the case for the minerals that may structurally include trace elements and potential radionuclides such like Ni, Cd, Co, Cr, Mn, Pb, ... The usual methods developed in order to predict...

Kimberlite is described as a diverse and complex hybrid rock in the literature. It is also described as volatile rich, potassic, ultrabasic, igneous rocks that occur as volcanic pipes, dykes and sills1. The minerals present in kimberlites vary widely and can include from trace to predominance any of the following minerals: apatite, calcite, chlorite, diopside (pyroxene), magnetite, monticellite...

The formation resistivity factor evaluation of brine-filled reservoir rock is an essential part of electrical resistivity log interpretation in petroleum exploration. Empirical relations such as Archie’s law are widely employed to model the relationship between the formation resistivity factor and porosity. Historically, the Archie cementation exponent has been obtained from experimental labora...