The Kamar-e-Mehdi Formation (Callovian – Oxfordian) is the fill of a shelf lagoon situated in the western and central parts of the so-called Tabas Block for a N-S distance of 200-300 km. From the predominantly fine-grained carbonates, which in the depocenter reach more than 1000 m in thickness, 69 taxa of bivalves are described, which differ greatly in their preservation depending on their orig...

The El Escorial marbles (Cushamen Metamorphic Complex) along with amphibolites form metamorphic septa within the permian granitoids of Mamil Choique Formation (261-286 Ma). metamorphism, determined in granulite facies migmatic gneisses cropping out 120 km southwest Escorial, occurs at 311 ± 27 Ma (CHIME method monazite). are calcitic (calcite > 95%, R.I.: 0.5 to 2.5%) and show 87Sr/86Sr valu...

Crystals formed in biological tissues often adopt remarkable morphologies that are thought to be determined mainly by the shapes of the confined spaces in which they grow. Another possible way of controlling crystal shape, demonstrated only in vitro, is by means of specialized proteins preferentially interacting with certain crystal faces. In so doing, they reduce the rate of growth in these di...

Organisms can exert a remarkable degree of control over crystal growth. One way of achieving this is by the adsorption of specialized macromolecules on specific planes of the growing crystals. With continued growth of the crystal, the macromolecules are incorporated inside the crystal bulk. Their presence does not change the crystal structure, but creates discontinuities in the perfect lattice....

Nigeria has an abundance of valuable solid minerals and rocks which can generate revenue for the government if they are fully exploited. Carbonate rock is one such that occur prominently in Igwe Igarra area Edo State. Five (5) carbonate samples (Four marble One Calcsilicate) were subjected to geochemical analyses. A petrographic study reveals calcsilicate contain calcite, quartz, microcline, pl...

Aragonite plays an important role in the biomineralization of serpulid polychaetes. Aragonitic structures are present a wide range species, but they mostly belong to one clade. marine environments, including deep ocean. tube microstructures were studied using scanning electron microscope. X-ray powder diffraction was used identify aragonite. is build five different types tubes. The most common ...