Universal Product Code. The Universal Product Code (UPC) is a barcode symbology that is widely used in the United States, Canada, United Kingdom, Australia, New Zealand, in Europe and other countries for tracking trade items in stores. UPC (technically refers to UPC-A) consists of 12 numeric digits, that are uniquely assigned to each trade item. Along with the related EAN barcode, the UPC is the barcode mainly used for scanning of trade items at the point of sale, per GS1 specifications.
A-C. Abyssal Plain The flat area of the ocean basins between oceanic ridges and trenches or passive margins. Average depth of the abyssal plain is 4km below sea level. Typically the sedimentary rocks forming here are black shales and turbidites.Accretionary Wedge (prism) A zone of deformed sediment made up of thrust slices scraped off a subducting oceanic plate and added onto the over-riding plate.ontinental Crust A collective term for the crust that forming the continents; it has an average thickness of 35 km but can be up to 70 km under mountain ranges. Typically the composition is granitic with a density of 2.7 meaning that it is too buoyant to be subducted at convergent (destructive) plate margins.
Owing in part to their vast size, abyssal plains are currently believed to be a major reservoir of biodiversity. The abyss also exerts significant influence upon ocean carbon cycling, dissolution of calcium carbonate, and atmospheric CO2 concentrations over timescales of 100â1000 years.ying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth âs surface. They are among the flattest, smoothest and least explored regions on Earth.