A Global Boundary Stratotype Section and Point, abbreviated GSSP, is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted by the International Commission on Stratigraphy, a part of the International Union of Geological Sciences. Most, but not all, GSSPs are based on paleontological changes. Hence GSSPs are described in terms of transitions between different faunal stages, though far more faunal stages have been described than GSSPs; the GSSP definition effort commenced in 1977. As of 2012, 64 of the 101 stages that need a GSSP have been formally defined. A geologic section has to fulfill a set of criteria to be adapted as a GSSP by the ICS; the following list summarizes the criteria: A GSSP has to define the lower boundary of a geologic stage. The lower boundary has to be defined using a primary marker. There should be secondary markers; the horizon in which the marker appears should have minerals.
The marker has to have regional and global correlation in outcrops of the same age The marker should be independent of facies. The outcrop has to have an adequate thickness Sedimentation has to be continuous without any changes in facies The outcrop should be unaffected by tectonic and sedimentary movements, metamorphism The outcrop has to be accessible to research and free to access; this includes that the outcrop has to be located where it can be visited has to be kept in good condition, in accessible terrain, extensive enough to allow repeated sampling and open to researchers of all nationalities. The Precambrian-Cambrian boundary GSSP at Fortune Head, Newfoundland is a typical GSSP, it is set aside as a nature preserve. A continuous section is available from beds that are Precambrian into beds that are Cambrian; the boundary is set at the first appearance of a complex trace fossil Treptichnus pedum, found worldwide. The Fortune Head GSSP is unlikely to be built over. Nonetheless, Treptichnus pedum is less than ideal as a marker fossil as it is not found in every Cambrian sequence, it is not assured that it is found at the same level in every exposure.
In fact, further eroding its value as a boundary marker, it has since been identified in strata 4m below the GSSP! However, no other fossil is known. There is no radiometrically datable bed at the boundary at Fortune Head, but there is one above the boundary in similar beds nearby; these factors have led some geologists to suggest. Once a GSSP boundary has been agreed upon, a "golden spike" is driven into the geologic section to mark the precise boundary for future geologists; the first stratigraphic boundary was defined in 1977 by identifying the Silurian-Devonian boundary with a bronze plaque at a locality called Klonk, northeast of the village of Suchomasty in the Czech Republic. GSSPs are sometimes referred to as Golden Spikes; because defining a GSSP depends on finding well-preserved geologic sections and identifying key events, this task becomes more difficult as one goes farther back in time. Before 630 million years ago, boundaries on the geologic timescale are defined by reference to fixed dates, known as "Global Standard Stratigraphic Ages".
Body form European Mammal Neogene Fauna Geologic time scale New Zealand geologic time scale List of GSSPs North American Land Mammal Age Type locality Hedberg, H. D. International stratigraphic guide: A guide to stratigraphic classification and procedure, New York, John Wiley and Sons, 1976 International Stratigraphic Chart from the International Commission on Stratigraphy GSSP table with pages on each ratified GSSP from the ICS Subcommission for Stratigraphic Information USA National Park Service Washington State University Web Geological Time Machine Eon or Aeon, Math Words - An alphabetical index The Global Boundary Stratotype Section and Point: overview Chart of The Global Boundary Stratotype Sections and Points: chart Table of Global Boundary Stratotype Sections and Points with links to summary pages for each one: chart GSSPs and Continental drift 3D views Geotime chart displaying geologic time periods compared to the fossil record - Deals with chronology and classifications for laymen
Fabiano Augusto Martins Silveira is a Brazilian lawyer and politician. He is a Legislative Advisor to the Federal Senate of Brazil and was the Minister of Transparency and Control of Brazil. Silveira holds a BA, Masters and PhD in Law from the Federal University of Minas Gerais and carried out post-doctoral studies at the University of Rome "La Sapienza" from 2006 and 2007. Silveira has served as a substitute teacher at the Law School of Federal University of Minas Gerais and the Pontifical Catholic University of Minas Gerais, he has been a visiting professor to several specialized post-graduate courses at public and private institutions. He has served as the legislative consultant of the Brazilian Senate in the areas of criminal law, criminal procedure, penal law since 2002. Silveira was a member of the Reform of the Criminal Procedure Code Committee of the Senate from 2008 to 2009 and the Management Commission of the II Republican Pact of State for Justice System More Affordable and Agile Justice System from 2009 to 2010.
He served as councilor of the National Council of the Public Ministry from 2011 to 2013 and the Brazilian National Justice Council from 2013 to 2015, was retained in this role for the 2015-2017 term. He held the role of National Justice Ombudsman from January 14, 2015 to January 14, 2016. Silveira was appointed to as Minister to the newly created Ministry of Transparency and Control by acting-president Michel Temer on May 12, 2016, he resigned from the position on May 31, 2016. Recordings were released by the press that suggest his criticism of both the large-scale investigation of Petrobras, the Brazilian state oil company, the anti-corruption campaign Operation Car Wash
The George B. Swan House is a historic building located on the east side of Davenport, United States, it has been listed on the National Register of Historic Places since 1983. George B. Swan was the yardmaster for Rock Island and Pacific Railroad, their roundhouse and switching yards were located down Farnam Street from his house. He had this house constructed in 1881 when the lot was subdivided from the LeClaire family's homestead; the house is a two-story Greek Revival structure with a front gable. Decorative features such as chamfered posts with small brackets, decorative window surrounds, a diamond-shaped window in the gable end and a two-story projecting side bay make this a Vernacular idiom of the style. A double-leaf door serves as the main entrance into the house