Mangrove trees, which develop along tropical coasts, are known to use saline water uptake. In French Guiana, the high salinity condition is the result of seawater evaporation on mud banks formed from the Amazon sediment flumes. In the back mangrove a few kilometres inland, groundwater, soil water and the xylem sap uptake in the trees remain highly salty, and only very tolerant plants like Avice...

the sorkh shale formation (lower triassic) crops out in parts of tabas block. this formation is composed of limestone, dolomite, sandstone, shale and gypsum. its lower contact with the permian rocks and its upper contact with the shotori formation is marked by distinct erosional unconformity. to determine the depositional environments of the sorkh shale formation, stratigraphic sections of goda...

Late Jurassic sandstones of the shallow-marine Sundance Formation contain authigenic chlorite minerals that occur as rosette-like pore fillings of interstratified berthierine/chamosite (B-C) and honeycomb-like pore linings of corrensite and discrete chlorite. B-C is nearly ubiquitous in Sundance sandstones, but is absent near the top of the formation, whereas corrensite and discrete chlorite we...

Seismological observations show that many destructive earthquakes nucleate within, or propagate through, thick sequences of carbonates and evaporites. For example, along the Apennines range (Italy) carbonate and evaporite sequences are present at hypocentral depths for recent major earthquakes (5.0oMwo6.3). However, little is known about the frictional properties of these rocks, which are domin...

At least potentially karstifiable rocks cover much of the surface of Egypt and northern Libya. Study of caves and other karstic features of this region has been hampered by lack of roads, rapid disintegration of the surface of friable, poorly consolidated limestone, wind-blown sand and other factors. Interbedding with marly aquicludes hampers speleogenesis locally. Calcareous and evaporite kars...

Recovery of prokaryotic body fossils from methane seep carbonates such as those of the Cretaceous Tepee Buttes of Colorado serves as a model for sampling in future astrobiological missions. The fossils, found primarily at the interface between paragenetic fabrics, suggest a sharp physicochemical gradient. Evidence of these microbial fossils occurs at a variety of scales. In the field, microbial...

Abstract Euhedral andradite crystals were found in trachyandesitic (latitic) lavas of the volcanic Andahua Group (AG) Central Andes. The AG comprises around 150 centers, most wich are monogenetic. studied is complexly zoned (enriched Ca and Al its core mantle, Fe this compositionally homogenous rim). core-mantle regions contain inclusions anhydrite, halite, S- Cl-bearing silicate glass, quartz,...