Carbonic acid (H2CO3) is a molecule right at the interface between organic and inorganic chemistry. In fact, according to some definitions it is an organic molecule, while according to others it is an inorganic molecule. Its exceptionality can also be recognized from the fact that it formally belongs neither to the mononor dicarboxylic acids, even though it is a C1 diprotic acid. The diprotic n...

Babolsar eastern coastal dunes have been developed along the southern coast of the Caspian Sea. The studied area is coordinated in N36°43' to N36°44' latitude and E52°44' to E52°52' longitude. The objectives of this research were to: Study mineralogy and geochemistry of sand dunes, to obtain chemical alteration index (CIA) and its relationship to climate and mineralogy, to de...

Electron backscatter diffraction (EBSD) is becoming a widely used technique to determine crystallographic orientation in biogenic carbonates. Despite this use, there is little information available on preparation for the analysis of biogenic carbonates. EBSD data are compared for biogenic aragonite and calcite in the common blue mussel, Mytilus edulis, using different types of resin and thickne...

Beach rock has only rarely been observed in the coasts. It is a hard costal sedimentary formations consisting of various beach sediments, lithified through the precipitation of carbonate cements. One such formation is noted on the South East Coast of Tamilnadu, India. The objective of this contribution is to collect and review information on reported occurrences, characteristics and formation m...

Research has been conducted into the diagenesis of the Luxembourg Sandstone. Literature studies were followed by a visit to the outcrop, after which thin sections were studied. The Luxembourg Sandstone Formation has been deposited in the Hettangian and Sinemurian, both lower Jurassic ages. A sea strait connecting the Northern German Basin and the Paris Basin was located in present day Luxembour...

A new diagnostic concept based on deep Raman spectroscopy is proposed permitting the non-invasive determination of the level of carbonate substitution in type II calcifications (HAP). The carbonate substitution has shown to be directly associated with the pathology of the surrounding breast tissue and different pathology groups can therefore be separated using specific features in the Raman spe...

a r t i c l e i n f o The purpose of this study is to investigate the role of filling materials (e.g., quartz sand and kaolin clay) in the interaction between a P-wave and a rock fracture. The specific fracture stiffness reflects the seismic response of a filled fracture, while the wave transmission coefficient describes P-wave transmission across the filled fracture. A series of experimental t...

Since rock fracture is a key property for different rock engineering applications, rock fracture measurement is often carried out in classifying the rock mass. Most geo-mechanics models (e.g. finite element) are of the equivalent continuum type in which fractures are represented not individually, but by their influence on a large element of the rock mass. Elastic modulus, for example, is obtain...

The carbonatite problem can be stated as follows: Are carbonatites genetically related to sedimentary carbonate rocks, or are they derived from a silicate parent material? The isotopic composition of strontium in 21 carbonatites and in several related alkaline rocks has been determined. The mean Sr87/$r86 ratio for the 21 carbonatites is 0.7065 + 0.0003. The Sr87/sr86 ratios of sedimentary carb...