A Dictionary of Earth Sciences

In 1850, M. A. Bravais confirmed that exact issues will be prepared spatially to supply 14 forms of general development. those 14 area lattices are referred to as ‘Bravais lattices’. four three 2 1 Bravais legislation See bravais rule. Break-back thrust Bravais rule (Bravais legislations) *Crystals are shaped through the repetition in 3 dimensions of a unit-cell constitution defined via *lattice breaker *Wave that's collapsing or breaking due to the wave drawing close the shore and attaining shallower water. The b breccia b lowering water intensity explanations the wavelength and velocity to diminish and the wave top to extend. therefore wave steepness raises and the wave turns into risky: it breaks while the wave peak is ready zero. eight instances the water intensity. various kinds of breaker were defined, e. g. spilling breakers (in which the wave breaks ahead, with damaged water spilling down front of the wave), and plunging breakers (in which the wave crest curls over a wide air pocket and falls vertically into the trough). breccia Coarse, *clastic, *sedimentary rock, the constituent clasts of that are angular. ‘Breccia’ actually capacity ‘rubble’ and implies a rock deposited very just about the resource zone. The time period can also be utilized to angular volcanic rocks from a volcanic vent (vent breccia). breccio-conglomerate A *conglomerate with *clasts that are either rounded and angular; it really is intermediate in personality among a *breccia and a *conglomerate. brecciola From the Italian, actually that means ‘little *breccia’, normally-graded beds of small, angular, *limestone *clasts. breeze rather mild wind, usually of convective beginning. The time period additionally comprises specific neighborhood air routine, e. g. mountain, land, and sea breezes. See additionally beaufort scale. breviconic utilized to a *cephalopod conch whilst it truly is brief and expands speedy. The *aperture is sort of vast. brick formed block of baked *clay used for development. frequently obloid fit with airplane faces and parallel edges; fine uniform texture with out fissures, air bubbles, or pebbles; a few are deep-salmon color from the iron content material of the clay. Small proportions of CaCO3 and *silt can be further for energy. the kind of clay most popular has a low water content material, to restrict shrinkage on drying, and is excessive in natural subject to lessen gasoline charges, e. g. the *Jurassic Oxford Clay of britain. Furnace, or refractory, bricks are made of *kaolinite, and so forth. brickearth Fine-grained silty deposit happening in south-eastern England. Of complicated beginning, it most likely resulted from the transforming of *loess, both via hillslope washing or via redeposition in status water. Brigantian The final *stage (326. 4–336 Ma in the past) of the *Visean Epoch. seventy eight vibrant spot A attribute part reversal on a reflection occasion, frequently indicating the presence of fuel. The *phase reversal is because of a marked lessen within the *acoustic impedence of gas-filled fabric which motives a powerful unfavorable reflection from the pinnacle of the gas-filled unit. frequently this is often observed via a *flat spot less than. brine A targeted resolution of inorganic salts, shaped by means of the partial evaporation of saline waters.