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A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it upwards. [1] If the magma finds a path to the surface, then the result will be a volcanic eruption ...
Magma that cools slowly within a magma chamber usually ends up forming bodies of plutonic rocks such as gabbro, diorite and granite, depending upon the composition of the magma. Alternatively, if the magma is erupted it forms volcanic rocks such as basalt , andesite and rhyolite (the extrusive equivalents of gabbro, diorite and granite ...
Cavitation can occur in the xylem of vascular plants. [58] [59] The sap vaporizes locally so that either the vessel elements or tracheids are filled with water vapor. Plants are able to repair cavitated xylem in a number of ways. For plants less than 50 cm tall, root pressure can be sufficient to redissolve the vapor.
Geothermal activity mostly appears in volcanic provinces, where it is fueled by the presence of a magma chamber. In some rare cases it can be caused by underground fires or by large deposits of radioactive elements. Other sources of internal heating can be gravitational differentiation of substances, tidal friction, metamorphism, or phase ...
Substomatal cavity. In plants, the substomatal cavity is the cavity located immediately proximal to the stoma. It acts as a diffusion chamber connected with intercellular air spaces and allows rapid diffusion of carbon dioxide and other gases (such as plant pheromones) in and out of plant cells .
Magma emplacement can take place at any depth above the source rock. [4] Magma emplacement is primarily controlled by the internal forces of magma including buoyancy and magma pressure. [2] Magma pressure changes with depth as vertical stress is a function of the depth. [20] Another parameter of magma emplacement is the rate of magma supply. [2]
A crystal mush is magma that contains a significant amount of crystals (up to 50% of the volume) suspended in the liquid phase (melt). [1] As the crystal fraction makes up less than half of the volume, there is no rigid large-scale three-dimensional network as in solids. [2] As such, their rheological behavior mirrors that of absolute liquids.
Plasmodesma. The structure of a primary plasmodesma. CW= cell wall, CA= callose, PM= plasma membrane, ER= endoplasmic reticulum, DM=desmotubule, Red circles= actin, Purple circles and spokes=other unidentified proteins [1] Plasmodesmata (singular: plasmodesma) are microscopic channels which traverse the cell walls of plant cells [2] and some ...