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Pipe Rock
''Skolithos'' (formerly spelled ''Scolithus'' or ''Skolithus'') is a common trace fossil ichnogenus that is, or was originally, an approximately vertical cylindrical burrow. It is produced by a variety of organisms in shallow marine environments globally and appear as lineated features in sedimentary rocks. Depositional environments ''Skolithos'' burrows range in age from early Cambrian to the present and are found throughout the world. They occur in sediments and sedimentary rocks, primarily sands and sandstones. They are typically marine in origin, and are commonly associated with high-energy environments close to the shoreline. They have also been reported from freshwater lacustrine settings, but have rarely been described from carbonate rocks. Vertical ''Skolithos'' burrows can also occur in alluvial sediments such as braided river deposits, where the periodic fluctuation of water is an important factor in the formation of this structure. This periodic water fluctuation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moine Thrust Belt
The Moine Thrust Belt or Moine Thrust Zone is a linear tectonic feature in the Scottish Highlands which runs from Loch Eriboll on the north coast south-west to the Sleat peninsula on the Isle of Skye. The thrust belt consists of a series of thrust faults that branch off the Moine Thrust itself. Topographically, the belt marks a change from rugged, terraced mountains with steep sides sculptured from weathered igneous, sedimentary and metamorphic rocks in the west to an extensive landscape of rolling hills over a metamorphic rock base to the east. Mountains within the belt display complexly folded and faulted layers and the width of the main part of the zone varies up to , although it is significantly wider on Skye. Discovery The presence of metamorphic gneisses and schists lying apparently stratigraphically above sedimentary rocks of lower Paleozoic age in the Northwest Highlands had been known since the early 19th century, convincing Roderick Murchison that the change was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic Life Of British Columbia
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean but even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic Life Of Alberta
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean but even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burrow Fossils
Burrow fossils are the remains of burrows - holes or tunnels excavated into the ground or seafloor - by animals to create a space suitable for habitation, temporary refuge, or as a byproduct of locomotion preserved in the rock record. Because burrow fossils represent the preserved byproducts of behavior rather than physical remains, they are considered a kind of trace fossil. One common kind of burrow fossil is known as Skolithos, and the similar Trypanites, Ophiomorpha and Diplocraterion. Vertebrate burrows Fish burrows Fossil Lungfish burrows are preserved in the Rocky Point Member of the Chinle Formation in Canyonlands National Park. Invertebrate burrows Examples are Treptichnus pedum ''Treptichnus'' (formerly named ''Phycodes'', ''Manykodes'' by J. Dzik, and also known as ''Trichophycus''See e.gfossiilid.info: paleodiversity in Baltoscandia: Trichophycus pedum/ref>) is the preserved burrow of an animal. As such, it is regar ... and Arenicolites franconicus. Footnotes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheology
Rheology (; ) is the study of the flow of matter, primarily in a fluid ( liquid or gas) state, but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied force. Rheology is a branch of physics, and it is the science that deals with the deformation and flow of materials, both solids and liquids.W. R. Schowalter (1978) Mechanics of Non-Newtonian Fluids Pergamon The term ''rheology'' was coined by Eugene C. Bingham, a professor at Lafayette College, in 1920, from a suggestion by a colleague, Markus Reiner.The Deborah Number The term was inspired by the of |
Loch Eriboll
__NOTOC__ Loch Eriboll (Scottish Gaelic: "Loch Euraboil") is a long sea loch on the north coast of Scotland, which has been used for centuries as a deep water anchorage as it is safe from the often stormy seas of Cape Wrath and the Pentland Firth. Bronze Age remains can be found in the area, including a souterrain and a very well preserved wheelhouse on the hillside above the west shore. A small scale lime industry developed here in the 19th century and Ard Neakie, a promontory on the eastern shore of the loch, had four large lime kilns developed in around 1870.Ard Neackie, Limekilns, Quarry Canmore. Retrieved 11 April 2021. Before the development of the coast road around the loch in 1890, the Heilam ferry ran from the quay at |
Foliation (geology)
Foliation in geology refers to repetitive layering in metamorphic rocks.Marshak, Stephen, ''Essentials of Geology,'' W. W. Norton 3rd Ed, 2009 Each layer can be as thin as a sheet of paper, or over a meter in thickness. The word comes from the Latin ''folium'', meaning "leaf", and refers to the sheet-like planar structure. It is caused by shearing forces (pressures pushing different sections of the rock in different directions), or differential pressure (higher pressure from one direction than in others). The layers form parallel to the direction of the shear, or perpendicular to the direction of higher pressure. Nonfoliated metamorphic rocks are typically formed in the absence of significant differential pressure or shear. Foliation is common in rocks affected by the regional metamorphic compression typical of areas of mountain belt formation (orogenic belts). More technically, foliation is any penetrative planar fabric present in metamorphic rocks. Rocks exhibiting foliat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vein (geology)
In geology, a vein is a distinct sheetlike body of crystallized minerals within a rock. Veins form when mineral constituents carried by an aqueous solution within the rock mass are deposited through precipitation. The hydraulic flow involved is usually due to hydrothermal circulation. Veins are classically thought of as being the ones in the body not the rock veins and arteries planar fractures in rocks, with the crystal growth occurring normal to the walls of the cavity, and the crystal protruding into open space. This certainly is the method for the formation of some veins. However, it is rare in geology for significant open space to remain open in large volumes of rock, especially several kilometers below the surface. Thus, there are two main mechanisms considered likely for the formation of veins: ''open-space filling'' and ''crack-seal growth''. Open space filling Open space filling is the hallmark of epithermal vein systems, such as a stockwork, in greisens or in cert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defining the val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protolith
A protolith () is the original, unmetamorphosed rock from which a given metamorphic rock is formed. For example, the protolith of a slate is a shale or mudstone. Metamorphic rocks can be derived from any other kind of non-metamorphic rock and thus there is a wide variety of protoliths. Identifying a protolith is a major aim of metamorphic geology. Protoliths are non-metamorphic rocks and have no protoliths themselves. The non-metamorphic rocks fall into two classes: sedimentary rocks, formed from sediment, and igneous rocks, formed from magma. The source of the sediment of a sedimentary rock is termed its provenance. Magmatic protoliths can be further divided into three categories: ultramafic rock, mafic rock, and quartzo-feldspathic rock. Similarly, sedimentary protoliths can be classified as quartzo-feldspathic, pelitic, carbonate rocks, or some mixture of the three. On a geological time scale, the first protoliths were first formed shortly after the formation of the Earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
