compared to quartz sand, the shear behavior of carbonate sand differs in  appearance, origin, and kind. carbonate sand is found mainly in the northern coast of the persian gulf and the oman sea. in this research, a comparison is made between the shear behavior of carbonate sand retrieved from the eastern region of the chabahar port, located north of the oman sea, and quartz sand obtained from f...

The problem of damage to structures in expansive soils is world wide. These soils are very often referred as black cotton soils. The properties of black cotton soil may be improved to make the soil suitable for construction purposes. There are several techniques to improve the soil properties like sand cushions, CNS layer techniques, sand columns, stone columns, vibration techniques and by addi...

Biological processes may provide great and previously unexplored opportunities for cost-effective, in situ improvement of the engineering properties of soil. A laboratory study was conducted to evaluate the changes in geomechanical properties of sand attributable to the formation of calcium precipitates induced through ureolysis catalyzed by Sporosarcina pasteurii (S. pasteurii). Specifically, ...

using of different systems of soil plough after changing unconsciously and non-scientific of land use, other soil physical and chemical characteristics affected. this fact, especially in marginal lands and mountainous regions is more visible. this research compared with the purpose of studying land use changing on some soil physical and chemical characters like very tiny sand percent, ph, ec, c...

in this study, a researching program is conducted by cyclic triaxial test to determine the post-cyclic behavior of bushehr carbonate sand retrieved from the north of the persian gulf, under anisotropic consolidation at 200 kpa confining pressure. the article compares the post-cyclic monotonic strength and excess pore water pressures generated after the test with the pre-cyclic monotonic results...

Permeable sediments and associated microbial communities play a fundamental role in nutrient recycling within coral reef ecosystems by ensuring high levels of primary production in oligotrophic environments. A previous study on organic matter degradation within biogenic carbonate and terrigenous silicate reef sands in the Red Sea suggested that observed sand-specific differences in microbial ac...

this study aimed to evaluate the potential of image ratioing techniques to detect and map the extent and particle composition of sand dunes in the erg of gavkhouni in isfahan province. the 6/4 ratio index and also a new index called sadi which was calculated using landsat band 3, 6 and 7 were applied to a georeferenced landsat tm image. to evaluate the performance of ratio techniques, the extra...

a r t i c l e i n f o a b s t r a c t Keywords: microbial mats biostabilization waves ripples platform stromatolite morphology Elongated stromatolites are often used as indicators of current direction and shoreline orientation, especially in paleoenvironmental reconstructions. However, mechanisms that create shore-parallel, m-scale elongated stromatolite mounds in carbonate sand are not well un...

Coral-algae symbiosis is a key feature of tropical corals and is highly dependent on the efficiency with which solar energy is attenuated by the coral. Scleractinian corals are among the most efficient light collectors in nature because of the modulation of the internal light field in the coral skeleton. Interestingly, coral skeleton particles composing the sandy bottoms in reef margins sustain...