Reflection seismology (or seismic reflection) is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the Earth 's subsurface from reflected seismic waves.arine survey acquisition is not just limited to seismic vessels; it is also possible to lay cables of geophones and hydrophones on the sea bed in a similar way to how cables are used in a land seismic survey, and use a separate source vessel.
Psoriasis typically starts or worsens because of a trigger that you may be able to identify and avoid. Factors that may trigger psoriasis include: 1  Infections, such as strep throat or skin infections. 2  Injury to the skin, such as a cut or scrape, bug bite, or a severe sunburn. 3  Stress. 4  Cold weather. 5  Smoking. 6  Heavy alcohol consumption.
Plaque psoriasis is the most common form of the disease and appears as raised, red patches covered with a silvery white buildup of dead skin cells. These patches or plaques most often show up on the scalp, knees, elbows and lower back.They are often itchy and painful, and they can crack and bleed.hile scientists do not know what exactly causes psoriasis, we do know that the immune system and genetics play major roles in its development. Usually, something triggers psoriasis to flare. The skin cells in people with psoriasis grow at an abnormally fast rate, which causes the buildup of psoriasis lesions.