page_title: Asphalt
hierarchical_section_title: Asphalt
caption_attribution_description: Natural formed Bitumen collected at the Dead Sea shore
context_page_description: Asphalt, also known as bitumen, is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. The word is derived from the Ancient Greek ἄσφαλτος ásphaltos. The Pitch Lake is the largest natural deposit of asphalt in the world, estimated to contain 10 million tons. It is located in La Brea in southwest Trinidad, within the Siparia Regional Corporation.
  The primary use of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs.
  In material sciences and engineering, the terms "asphalt" and "bitumen" are often used interchangeably to mean both natural and manufactured forms of the substance, although there is regional variation as to which term is most common. Worldwide, geologists tend to favor the term "bitumen" for the naturally occurring material.
context_section_description: Asphalt, also known as bitumen (UK: /ˈbɪtjʊmɪn/, US: /bɪˈtjuːmən, baɪ-/), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. The word is derived from the Ancient Greek ἄσφαλτος ásphaltos. The Pitch Lake is the largest natural deposit of asphalt in the world, estimated to contain 10 million tons. It is located in La Brea in southwest Trinidad, within the Siparia Regional Corporation.
  The primary use (70%) of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs.
  In material sciences and engineering, the terms "asphalt" and "bitumen" are often used interchangeably to mean both natural and manufactured forms of the substance, although there is regional variation as to which term is most common. Worldwide, geologists tend to favor the term "bitumen" for the naturally occurring material. For the manufactured material, which is a refined residue from the distillation process of selected crude oils, "bitumen" is the prevalent term in much of the world; however, in American English, "asphalt" is more commonly used. To help avoid confusion, the phrase "liquid asphalt", "asphalt binder", or "asphalt cement" is used in the U.S. Colloquially, various forms of asphalt are sometimes referred to as "tar", as in the name of the La Brea Tar Pits, although tar is a different material.
  Naturally occurring asphalt is sometimes specified by the term "crude bitumen". Its viscosity is similar to that of cold molasses while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as "refined bitumen". The Canadian province of Alberta has most of the world's reserves of natural asphalt in the Athabasca oil sands, which cover 142,000 square kilometres (55,000 sq mi), an area larger than England.
  Asphalt properties change with temperature, which means that there is a specific range where viscosity permits adequate compaction by providing lubrication between particles during the compaction process. Low temperature prevents aggregate particles from moving, and the required density is not possible to achieve. Computer simulations of simplified model systems are able to reproduce some of asphalt's characteristic properties.
caption: Natural bitumen from the Dead Sea
exif: {"Image ImageDescription": "PENTAX Image", "Image Make": "PENTAX Corporation", "Image Model": "PENTAX Optio E10", "Image Software": "V1.00", "Image DateTime": "2007:03:26 21:13:51", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "538", "Image PrintIM": "[80, 114, 105, 110, 116, 73, 77, 0, 48, 51, 48, 48, 0, 0, 33, 0, 1, 0, 22, 0, ... ]", "EXIF ExposureTime": "3059/125000", "EXIF FNumber": "47/10", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "200", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2007:03:26 21:13:51", "EXIF DateTimeDigitized": "2007:03:26 21:13:51", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "3", "EXIF MeteringMode": "CenterWeightedAverage", "EXIF Flash": "Flash fired, auto mode", "EXIF FocalLength": "29/2", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2816", "EXIF ExifImageLength": "2112", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard", "EXIF GainControl": "High gain up", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal"}