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Cosheston Group
The Cosheston Group is an early Devonian lithostratigraphic group (a sequence of rock strata) in west Wales. The name is derived from the village of Cosheston in south Pembrokeshire. The Group comprises (in ascending order) the Llanstadwell, Burton Cliff, Mill Bay, Lawrenny Cliff and New Shipping formations. The strata are exposed in the Milford Haven area of southern Pembrokeshire where several partial type sections are defined. The outcrop extends around the northern and southern shores of the Haven. It is bounded to the north by the Benton Fault between the villages of Rosemarket and Lawrenny, and extends east to New Shipping and west almost to the town of Milford Haven itself. The rocks of this group have also previously been known as the Cosheston Beds. Stratigraphy Llanstadwell, Burton Cliff and Mill Bay formations This sequence is largely green sandstones with lesser amounts of red sandstone and including intraformational conglomerates and some siltstones. Lawren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (stratigraphy)
In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distinguished from its neighbor by its lithology, but all were deposited in the same vast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock Strata
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as either being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian System Of Europe
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clastic Rock
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks by physical weathering.Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-5 Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport, whether in suspension or as bed load, and in sediment deposits. Sedimentary clastic rocks Clastic sedimentary rocks are rocks composed predominantly of broken pieces or ''clasts'' of older weathered and eroded rocks. Clastic sediments or sedimentary rocks are classified based on grain size, clast and cementing material (matrix) composition, and texture. The classification factors are often useful in determining a sample's environment of deposition. An example of clastic environment would be a river system in which the full range of grains being transported by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milford Haven
Milford Haven ( cy, Aberdaugleddau, meaning "mouth of the two Rivers Cleddau") is both a town and a community in Pembrokeshire, Wales. It is situated on the north side of the Milford Haven Waterway, an estuary forming a natural harbour that has been used as a port since the Middle Ages. The town was founded in 1790 by Sir William Hamilton, who designed a grid pattern. It was originally intended to be a whaling centre, though by 1800 it was developing as a Royal Navy dockyard which it remained until the dockyard was transferred to Pembroke in 1814. It then became a commercial dock, with the focus moving in the 1960s, after the construction of an oil refinery built by Esso, to logistics for fuel oil and liquid gas. By 2010, the town's port had become the fourth largest in the United Kingdom in terms of tonnage, and continues its important role in the United Kingdom's energy sector with several oil refineries and one of the biggest LNG terminals in the world. Milford Haven is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lawrenny
Lawrenny is a village and parish in the community and electoral ward of Martletwy in the county of Pembrokeshire, Wales. It is on a peninsula of the River Cleddau estuary upriver from Milford Haven where it branches off towards the Cresswell and Carew Rivers and is in the Pembrokeshire Coast National Park. Description The village extends down to the Estuary to Lawrenny Quay half a mile from the centre, where there is a busy yacht station and caravan park. It provides most of the central rural facilities for the Martletwy ward, including a shop, mobile post office, cricket and football clubs, village hall and church. The community owns and operates the Millennium Youth Hostel and the village shop. The ''Lawrenny Arms'' and the Quayside Tearooms have recently become popular destinations in the area for both boaters and walkers. The village has its own community-run broadband service which provides Internet access across the village as well as to communities on the other side o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosemarket
Rosemarket is a village, parish and community in Pembrokeshire, Wales, north of Milford Haven. Name The name does not refer to flowers but to the hundred of Roose, the former Welsh cantref of Rhos. History The village was a marcher borough founded by the Knights Hospitallers in the 12th century. It appears on a 1578 parish map of Pembrokeshire. Owen, in 1603, described it as one of nine Pembrokeshire "boroughs in decay". The parish church, like many in the former lands of Rhos, is dedicated to the 6th-century Breton prince and Welsh saint Ismael. The village has a medieval dovecote and a large hillfort. Local government The village has its own elected community council and is part of the electoral ward of Burton for the purposes of elections to Pembrokeshire County Council Pembrokeshire County Council ( cy, Cyngor Sir Penfro) is the governing body for Pembrokeshire, one of the Principal Areas of Wales. Political control The first election to the council was held in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benton Fault
The Benton Fault is a geological fault in southern Pembrokeshire in Wales that was active as a normal fault during the deposition of the Old Red Sandstone during the Devonian period, forming a thick half graben. During the Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ..., the Benton Fault was strongly inverted as part of the Variscan Orogeny. See also * List of geological faults of Wales References Geology of Wales {{Wales-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Section
A stratotype or type section in geology is the physical location or outcrop of a particular reference exposure of a stratigraphic sequence or stratigraphic boundary. If the stratigraphic unit is layered, it is called a stratotype, whereas the standard of reference for unlayered rocks is the type locality. Also it can be defined as "The particular sequence of strata chosen as standard of reference of a layered stratigraphic unit." When a stratigraphic unit is nowhere fully exposed, the original type section may be supplemented with reference sections covering the full thickness of the unit. A reference section may also be defined when the original type section is poorly exposed, or for historical units which were designated without specifying a type section according to more modern standards. See also * Global Boundary Stratotype Section and Point A Global Boundary Stratotype Section and Point (GSSP) is an internationally agreed upon reference point on a stratigraphic se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milford Haven Waterway
Milford Haven Waterway (''Welsh: Dyfrffordd Aberdaugleddau'') is a natural harbour in Pembrokeshire, Wales. It is a ria or drowned valley which was flooded at the end of the last ice age. The Daugleddau estuary winds west to the sea. As one of the deepest natural harbours in the world, it is a busy shipping channel, trafficked by ferries from Pembroke Dock to Ireland, oil tankers and pleasure craft. Admiral Horatio Nelson, visiting the haven with the Hamiltons, described it as the next best natural harbour to Trincomalee in Ceylon (today's Sri Lanka ) and "the finest port in Christendom".Wing Commander Ken McKay ''A Vision of Greatness: The History of Milford 1790–1990'', Brace Harvatt Associates, 1989. Much of the coastline of the Waterway is designated as a Site of Special Scientific Interest, listed as Milford Haven Waterway SSSI. History Early history From the 790s until the Norman Invasion in 1066, the waterway was used occasionally by Vikings looking for shelte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as either being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (stratigraphy)
In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distinguished from its neighbor by its lithology, but all were deposited in the same vast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
