Gneiss is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures and pressures than schist. Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without a distinct cleavage.
Migmatite is a composite rock found in medium and high-grade metamorphic environments, commonly within Precambrian cratonic blocks. It consists of two or more constituents often layered repetitively: one layer is an older metamorphic rock that was reconstituted subsequently by partial melting ("neosome"), while the alternate layer has a pegmatitic, aplitic, granitic or generally plutonic appearance ("paleosome"). Commonly, migmatites occur below deformed metamorphic rocks that represent the base of eroded mountain chains.
Arthur Holmes was an English geologist who made two major contributions to the understanding of geology. He pioneered the use of radiometric dating of minerals, and was the first earth scientist to grasp the mechanical and thermal implications of mantle convection, which led eventually to the acceptance of plate tectonics.
Sir Lewis Leigh Fermor, OBE, FRS, was a British chemist and geologist and the first president of the Indian National Science Academy and a director of the Geological Survey of India (1930-1935). His son was the writer and traveller Sir Patrick Leigh Fermor.
Rapakivi granite is a hornblende-biotite granite containing large round crystals of orthoclase each with a rim of oligoclase. The name has come to be used most frequently as a textural term where it implies plagioclase rims around orthoclase in plutonic rocks. Rapakivi is a Finnish compound of "rapa" and "kivi", because the different heat expansion coefficients of the component minerals make exposed rapakivi crumble easily into sand.
The Yilgarn Craton is a large craton that constitutes a major part of the Western Australian land mass. It is bounded by a mixture of sedimentary basins and Proterozoic fold and thrust belts. Zircon grains in the Jack Hills, Narryer Terrane have been dated at ~4.27 Ga, with one detrital zircon dated as old as 4.4 Ga.
Alfred Harker FRS was an English geologist who specialised in petrology and interpretive petrography. He was Lecturer in Petrology at the University of Cambridge for many years, and carried out field mapping for the Geological Survey of Scotland and geological studies of western Scotland and the Isle of Skye. He and other British geologists pioneered the use of thin sections and the petrographic microscope in interpretive petrology.
The Murchison Medal is an academic award established by Roderick Murchison, who died in 1871. First awarded in 1873, it is normally given to people who have made a significant contribution to geology by means of a substantial body of research and for contributions to 'hard' rock studies. One of the closing public acts of Murchison's life was the founding of a chair of geology and mineralogy in the University of Edinburgh. Under his will there was established the Murchison Medal and geological fund to be awarded annually by the council of the Geological Society of London.
Pentti Elias Eskola was a Finnish geologist who specialised in the petrology of granites and developed the concept of metamorphic facies. He won the Wollaston Medal in 1958, the Vetlesen Prize in 1964, and was given a state funeral upon his death. The mineral eskolaite is named in his honor.
Charles Kenneth Leith was an American geologist. He was head of the University of Wisconsin geology department for 30 years. In 1942, he was awarded the Penrose Medal by the Geological Society of America, the highest award given in the geosciences.
Fredrik Johan Wiik, also known as F.J. Wiik, was a Finnish geologist and mineralogist; in 1877, he was named the first professor of geology and mineralogy at the Imperial Alexander University of Finland, where his students included Jakob Sederholm and Wilhelm Ramsay. He was also the first scientist in Finland to use a petrographic microscope.
Janet Vida Watson FRS FGS (1923–1985) was a British geologist. She was a professor of Geology at Imperial College, a rapporteur for the International Geological Correlation Program (IGCP) (1977–1982) and a vice president of the Royal Society (1983–1984). In 1982 she was elected president of the Geological Society of London, the first woman to occupy that position. She is well known for her contribution to the understanding of the Lewisian complex and as an author and co-author of several books including Beginning Geology and Introduction to Geology.
The Geological Survey of Finland is the geological survey of Finland. The organization was founded in 1885 when Emperor Alexander III decreed that the Geological Survey of Finland be established. GTK is a research institution governed by the Finnish Ministry of Employment and the Economy, operating in Finland and globally.
Wilhelm Ramsay was a Finnish geologist. He became a member of the Royal Swedish Academy of Sciences in 1914 and in 1915 was accepted into the Royal Physiographic Society in Lund. He coined the terms Fennoscandia (1900) and Postjotnian (1909). Ramsay also coined the term ijolite.
Stephen Erwin Moorbath was a British geochronologist. He set up (1956–58) and then directed the Geological Age and Isotope Research Group at the University of Oxford, before retiring.
The geology of Finland is made up of a mix of geologically very young and very old materials. Common rock types are orthogneiss, granite, metavolcanics and metasedimentary rocks. On top of these lies a widespread thin layer of unconsolidated deposits formed in connection to the Quaternary ice ages, for example eskers, till and marine clay. The topographic relief is rather subdued because mountain massifs were worn down to a peneplain long ago.
Kshitindramohan Naha (1932–1996) was an Indian geologist and a professor and CSIR Emeritus scientist at the Indian Institute of Technology, Kharagpur. He was known for his studies on structural geology of Precambrian era and was an elected fellow of the Indian National Science Academy, and the Indian Academy of Sciences. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards for his contributions to Earth, Atmosphere, Ocean and Planetary Sciences in 1972.
The geology of Sweden is the regional study of rocks, minerals, tectonics, natural resources and groundwater in the country. The oldest rocks in Sweden date to more than 2.5 billion years ago in the Precambrian. Complex orogeny mountain building events and other tectonic occurrences built up extensive metamorphic crystalline basement rock that often contains valuable metal deposits throughout much of the country. Metamorphism continued into the Paleozoic after the Snowball Earth glaciation as the continent Baltica collided with an island arc and then the continent Laurentia. Sedimentary rocks are most common in southern Sweden with thick sequences from the last 250 million years underlying Malmö and older marine sedimentary rocks forming the surface of Gotland.
Eduard Jean Louis Wenk was a Swiss geologist, petrographer, and mineralogist.
