normalmathematics

• arrangement and properties petroleum refining

  Paraffins can be arranged either in straight chains (normal paraffins, such as butane; see figure) or branched chains (isoparaffins). Most of the paraffin compounds in naturally occurring crude oils are normal paraffins, while isoparaffins are frequently produced in refinery processes. The normal paraffins are uniquely poor as motor fuels, while isoparaffins have good engine-combustion...

• Greek geometry mathematics

  ...to draw tangents to given conics (Book II); relations of chords intersecting in conics (Book III); the determination of the number of ways in which conics may intersect (Book IV); how to draw “normal” lines to conics (that is, lines meeting them at right angles; Book V); and the congruence and similarity of conics (Book VI).

• characteristics fault

  Faults are classified according to their angle of dip and their relative displacement. Normal dip-slip faults are produced by vertical compression as the Earth’s crust lengthens. The hanging wall slides down relative to the footwall. Normal faults are common; they bound many of the mountain ranges of the world and many of the rift valleys found along spreading margins of tectonic plates. Rift...

• earthquakes earthquake

  ...Lying over the footwall is the hanging wall. When rock masses slip past each other parallel to the strike, the movement is known as strike-slip faulting. Movement parallel to the dip is called dip-slip faulting. Strike-slip faults are right lateral or left lateral, depending on whether the block on the opposite side of the fault from an observer has moved to the right or left. In dip-slip...

formation of

• abyssal hills ocean

  Apparently the hills are constructed by two processes: volcanism and block faulting. The relative contribution of each may depend on the spreading rate. At slower rates, faulting of the oceanic crust is a dominant factor in forming the relief, and the relief of the hills is greater as the rate is slower. At the crest of a spreading centre, volcanism in the neovolcanic zone initiates the...

• Death Valley Death Valley

  ...is a graben, or rift valley, formed by the sinking of a tremendous expanse of rock lying between parallel uplifted, tilted-block mountain ranges to the east and west. A type of fault activity called block faulting, in which the movement is predominantly vertical, began to form the valley in the middle of the Tertiary Period (about 30 million years ago). As crustal blocks sank,...

• Lake Baikal Russia

  The area around Lake Baikal is one of massive block faulting in which major...

• type of galaxy ( in galaxy: Spiral galaxies )

  Spirals are characterized by circular symmetry, a bright nucleus surrounded by a thin outer disk, and a superimposed spiral structure. They are divided into two parallel classes: normal spirals and barred spirals. The normal spirals have arms that emanate from the nucleus, while barred spirals have a bright linear feature called a bar that straddles the nucleus, with the arms unwinding from the...

  in Cosmos: Classification of galaxies )

  ...groups: ellipticals and disks. Elliptical galaxies, denoted E, have roundish shapes. Disk galaxies, on the other hand, have flattened shapes. They can be further divided into two subcategories: ordinary spirals, denoted S, and barred spirals, denoted SB. In addition, there exists a transition type between ellipticals and spirals, which are often called lenticulars. The lenticular galaxies...

• definition albedo

  Albedo is usually differentiated into two general types: normal albedo and bond albedo. The former, also called normal reflectance, is a measure of a surface’s relative brightness when illuminated and observed vertically. The normal albedo of snow, for example, is nearly 1.0, whereas that of charcoal is about 0.04. Investigators frequently rely on observations of normal albedo to determine the...