page_title: Stratigraphy of the Cambrian
hierarchical_section_title: Stratigraphy of the Cambrian
caption_attribution_description: English: Ediacaran-Cambrian boundary section at Fortune Head, NL, containing the GSSP level, on a rare sunny day
context_page_description: The Stratigraphy of the Cambrian period currently has several schemes used for ordering geologic formations from the period. The International Commission on Stratigraphy−ICS scheme has set a stratotype section for the base of the Cambrian, dated quite accurately to 541 ± 1.0 million years ago. Russian and Chinese scientists have developed a different scheme.
  Stratigraphy relates to the order of rock units, without referring to their absolute ages. However, because fossils — which are traditionally the cornerstone of stratigraphy — are relatively rare in the Cambrian period, chronology has a significant part to play. If an absolute age can be obtained with a high degree of accuracy for different strata, their relative age can also be established.
  The base of the Cambrian is officially defined as the first appearance of a certain trace fossil, Treptichnus pedum. However, this fossil also appears in older rocks than the locality which officially marks the start of the period. However, there is a period of biological change which makes this time period a good one to demarkate the Cambrian from the earlier Phanerozoic eon's periods and the Precambrian supereon.
context_section_description: The Stratigraphy of the Cambrian period currently has several schemes used for ordering geologic formations from the period.  The International Commission on Stratigraphy−ICS scheme has set a stratotype section for the base of the Cambrian, dated quite accurately to 541 ± 1.0 million years ago.  Russian and Chinese scientists have developed a different scheme.
  Stratigraphy relates to the order of rock units, without referring to their absolute ages (which is chronology).  However, because fossils — which are traditionally the cornerstone of stratigraphy — are relatively rare in the Cambrian period, chronology has a significant part to play. If an absolute age can be obtained with a high degree of accuracy for different strata, their relative age can also be established.
  The base of the Cambrian is officially defined as the first appearance of a certain trace fossil, Treptichnus pedum. However, this fossil also appears in older rocks than the locality which officially marks the start of the period.  However, there is a period of biological change which makes this time period a good one to demarkate the Cambrian from the earlier Phanerozoic eon's periods and the Precambrian supereon. Consensus holds that fossils of the Ediacara biota disappear here, as do some shelly fossils and acritarchs; and a new small shelly fossil biota emerges.
caption: Ediacaran-Cambrian boundary section at Fortune Head, NL, containing the official base of the Cambrian period
exif: {"Image ImageDescription": "", "Image Make": "Canon", "Image Model": "Canon PowerShot SX240 HS", "Image Orientation": "Horizontal (normal)", "Image XResolution": "180", "Image YResolution": "180", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2017:06:16 04:15:29", "Image YCbCrPositioning": "Co-sited", "Image ExifOffset": "234", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "180", "Thumbnail YResolution": "180", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "5620", "Thumbnail JPEGInterchangeFormatLength": "4205", "EXIF ExposureTime": "1/640", "EXIF FNumber": "4", "EXIF ISOSpeedRatings": "100", "EXIF SensitivityType": "Standard Output Sensitivity and Recommended Exposure Index", "EXIF ExifVersion": "0230", "EXIF DateTimeOriginal": "2017:06:16 04:15:29", "EXIF DateTimeDigitized": "2017:06:16 04:15:29", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "5", "EXIF ShutterSpeedValue": "149/16", "EXIF ApertureValue": "4", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "29/8", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "9/2", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "4000", "EXIF ExifImageLength": "3000", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "4000", "Interoperability RelatedImageLength": "3000", "EXIF InteroperabilityOffset": "4852", "EXIF FocalPlaneXResolution": "1000000/61", "EXIF FocalPlaneYResolution": "1000000/61", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard", "EXIF CameraOwnerName": ""}