Clay-rich fault rocks have long been recognized to host distinctive fabric elements, and fault rock fabric is increasingly thought to play a fundamental role in fault mechanical behaviour in the brittle regime. Although the geometries of fabric elements in fault gouges have been described for almost a century, the genesis and evolution of these elements during shear, and their links to bulk mec...

a study of the diagenetic evolution of sandstones from panyu low-uplift in the pearl river mouth basin was carried out to unravel the controls on shelf margin sandstone reservoir quality. the reservoir rocks, oligocene volcanic clastic sandstones of the zhuhai formation, have a burial depth of 2765 to 3440 m. 70 samples were studied using the granulometric analyses, x-ray diffraction (xrd) anal...

a research program was conducted on different clay-bearing rocks selected from the ilam, sarpol-e zahab and tajarak regions (iran) to predict their slaking characteristics. the new durability apparatus (nested mesh drums) separates disintegrated particles varying from > 25.4 to < 2 mm as the drums were rotated. on the basis of the particle size distribution, the disintegration ratio (dr) was us...

A research program was conducted on different clay-bearing rocks selected from the Ilam, Sarpol-e Zahab and Tajarak regions (Iran) to predict their slaking characteristics. The new durability apparatus (nested mesh drums) separates disintegrated particles varying from > 25.4 to < 2 mm as the drums were rotated. On the basis of the particle size distribution, the disintegration ratio (DR) was us...

Clay-rich sediments from the Kajjansi, Kitiko, Kitetika, and Ntawo valleys in central Uganda were analyzed for mineralogical and chemical composition, including the rare earth element (REE) contents. The valleys are filled with Quaternary to Recent alluvial and lacustrine sands, silt, and gravels, which formed from the bed rock metasediments of the Buganda-Toro System and from granitoid rocks t...

Introduction: Secondary minerals identified by Mars Science Laboratory (MSL), together with their sedimentological and stratigraphic context, provide an unprecendented opportunity to constrain the nature of martian fluids and habitability. One of the main targets for the MSL mission within the new Extended Mission is the Hematite Ridge on the north, lower slopes of Mt. Sharp (Aeolis Mons). This...

The Paleocene-Eocene boundary (∼55.8 million years ago) is marked by an abrupt negative carbon isotope excursion (CIE) that coincides with an oxygen isotope decrease interpreted as the Paleocene-Eocene thermal maximum. Biogenic magnetite (Fe3O4) in the form of giant (micron-sized) spearhead-like and spindle-like magnetofossils, as well as nano-sized magnetotactic bacteria magnetosome chains, ha...

We studied the elastic moduli, ductile creep behavior, and brittle strength of shale-gas reservoir rocks from Barnett, Haynesville, Eagle Ford, and Fort St. John shale in a series of triaxial laboratory experiments. We found a strong correlation between the shale compositions, in particular, the volume of clay plus kerogen and intact rock strength, frictional strength, and viscoplastic creep. V...