The Zagros Mountains form the largest mountain range in Iran and southeastern Turkey. This mountain range has a length of 1,500 km. The highest point in the Zagros Mountains is Dena, the Zagros fold and thrust belt was formed by collision of two tectonic plates, the Eurasian Plate and the Arabian Plate. This collision primarily happened during the Miocene and folded the rocks that had been deposited from the Carboniferous to the Miocene in the geosyncline in front of the Iranian Plate. The process of collision continues to the present and as the Arabian Plate is being pushed against the Eurasian Plate, the Zagros Mountains, a relatively dense GPS network which covered the Iranian Zagros proves a high rate of deformation within the Zagros. The GPS results show that the current rate of shortening in the southeast Zagros is ~10 mm/yr, the north-south Kazerun strike-slip fault divides the Zagros into two distinct zones of deformation. The GPS results show different shortening directions along the belt, normal shortening in the southeast, the sedimentary cover in the SE Zagros is deforming above a layer of rock salt whereas in the NW Zagros the salt layer is missing or is very thin.
This different basal friction is partly responsible for the different topographies on either side of the Kazerun fault. Higher topography and narrower zone of deformation in the NW Zagros is observed whereas in the SE, deformation was spread more, stresses induced in the Earths crust by the collision caused extensive folding of the preexisting layered sedimentary rocks. Subsequent erosion removed softer rocks, such as mudstone and siltstone while leaving harder rocks, such as limestone and this differential erosion formed the linear ridges of the Zagros Mountains. The depositional environment and tectonic history of the rocks were conducive to the formation and trapping of petroleum, salt domes and salt glaciers are a common feature of the Zagros Mountains. Salt domes are an important target for exploration, as the impermeable salt frequently traps petroleum beneath other rock layers. The Zagros Mountains have a totally sedimentary origin and are primarily of limestone. In the Elevated Zagros or the Higher Zagros, the Paleozoic rocks could be found mainly in the upper and higher sections of the peaks of the Zagros Mountains along the Zagros main fault.
On the both sides of this fault, there are Mesozoic rocks, a combination of Triassic and Jurassic rocks that are surrounded by Cretaceous rocks on the both sides. The Folded Zagros is formed mainly of Tertiary rocks, with the Paleogene rocks south of the Cretaceous rocks, the mountains are divided into many parallel sub-ranges, and orogenically have the same age as the Alps. Irans main oilfields lie in the central foothills of the Zagros mountain range. The southern ranges of the Fars Province have somewhat lower summits and they contain some limestone rocks showing abundant marine fossils
Colossal Statue of Shapur I
The statue is about 35 m from the cave entrance, on the fourth of five terraces, lying approximately 3.4 m below the level of the cave entrance. Its height of about 6.7 m and breadth across the shoulders of more than 2 m make it one of the most impressive sculptures from the Sassanian period. The monumental sculpture is chiseled from a huge stalagmite grown in situ, after its fall, the sculpture was raised onto two concrete pillars, which are located near the original feet. The head and the body of the sculpture have remained well preserved while parts of its arms. The colossal statue is rich in detail and it is chiseled on every side with the same amount of extraordinary care and attention. The king wears a crenellated crown, a large piece of the front crenellation is missing, while the crenellations of both sides and the rear are well preserved. At the lower end of the crown, there is a wide diadem, the two bands of the diadem fall heavily down the back to the waist and widen from top to bottom.
Around twenty horizontal, parallel furrows cross on these bands, the head of the sculpture has been carved out in all its particulars symmetrically. The hairstyle of the statue shows a high degree of sculptural definition. The mass of hair on the side of the sculpture has remained intact while the ends of strands of hair on the right side are broken off. Of the left arm of the sculpture, only half remains, the missing left hand of the sculpture must have once rested on the sword handle. The right arm is broken off just below the axilla, a small part of the right underarm is still attached. The right hand is strongly weathered and rests on the waist, the clothing of the colossal statue consists of three pieces, an undervest, an upper garment and wide trousers. The upper garment of the sculpture fits tightly to the body, through its skin-tight fit, the shoulders, the upper arms and the chest of the king have been emphasized. The sculpted ornaments on the garment are quite remarkable insofar as they resemble flames flickering downward.
These are varyingly long, shaped in different ways and irregularly arranged. At the waist, the garment is held together tightly by a belt while a second belt. Only small parts of the legs of the sculpture have remained, the small remaining piece of the left thigh supports a conclusion that the ruler was wearing fluted trousers
A season is a division of the year marked by changes in weather and hours of daylight. Seasons result from the orbit of the Earth around the Sun. During May and July, the northern hemisphere is exposed to direct sunlight because the hemisphere faces the sun. The same is true of the hemisphere in November, December. It is the tilt of the Earth that causes the Sun to be higher in the sky during the months which increases the solar flux. However, due to lag, June and August are the hottest months in the northern hemisphere and December, January. In temperate and subpolar regions, four calendar-based seasons are recognized, summer, autumn or fall. Ecologists often use a model for temperate climate regions, vernal, serotinal, autumnal. Many tropical regions have two seasons, the rainy, wet, or monsoon season and the dry season, some have a third cool, mild, or harmattan season. Seasons often held special significance for agrarian societies, whose lives revolved around planting and harvest times, in some parts of the world, some other seasons capture the timing of important ecological events such as hurricane season, tornado season, and wildfire season.
The most historically important of these are the three seasons—flood and low water—which were previously defined by the annual flooding of the Nile in Egypt. The seasons result from the Earths axis of rotation being tilted with respect to its orbital plane by an angle of approximately 23.5 degrees, regardless of the time of year, the northern and southern hemispheres always experience opposite seasons. This is because during summer or winter, one part of the planet is directly exposed to the rays of the Sun than the other. For approximately half of the year, the northern hemisphere tips toward the Sun, for the other half of the year, the same happens, but in the southern hemisphere instead of the northern, with the maximum around December 21. The two instants when the Sun is directly overhead at the Equator are the equinoxes. Also at that moment, both the North Pole and the South Pole of the Earth are just on the terminator, and hence day and night are equally divided between the northern and southern hemispheres.
Around the March equinox, the northern hemisphere will be experiencing spring as the hours of daylight increase, the effect of axial tilt is observable as the change in day length and altitude of the Sun at noon during a year. Between this effect and the daylight hours, the axial tilt of the Earth accounts for most of the seasonal variation in climate in both hemispheres
An icicle is a spike of ice formed when water dripping or falling from an object freezes. Icicles can form during bright, but subfreezing weather, over time continued water runoff will cause the icicle to grow. Another set of conditions is during ice storms, when falling in air slightly below freezing slowly accumulates as numerous small icicles hanging from twigs, wires. Thirdly, icicles can form wherever water seeps out of or drips off vertical surfaces such as road cuts or cliffs, another influence is melting water, which might flow toward the icicle in a straight line or which might flow from several directions. Impurities in the water can lead to ripples on the surface of the icicles, icicles elongate by the growth of ice as a tube into the pendant drop. The wall of this ice tube is about 0.1 mm, as a result of this growth process, the interior of a growing icicle is liquid water. The growth of an icicle both in length and in width can be calculated and is a function of air temperature, wind speed.
The growth rate in length varies with time, and can in ideal conditions be more than 1 cm per minute. Given the right conditions, icicles may form in caves and they can form around salty water sinking from sea ice. These so-called brinicles can actually kill sea urchins and starfish, which was observed by BBC film crews near Antarctica, icicles can pose both safety and structural dangers. Icicles that hang from an object may fall and cause injury and/or damage to whoever or whatever is below them, in addition, ice deposits can be heavy. If enough icicles form on an object, such as a wire or a beam or pole and this can happen with roofs, where failure can damage nearby parked vehicles or the contents and occupants of the structure. Icicles on roofs can be associated with ice dams, which can cause damage as the water penetrates below the shingles. The story of an English youth who was killed by an icicle in 1776 has been often recounted. Large icicles that form on cliffs near highways have been known to fall and damage motor vehicles
Vietnam, officially the Socialist Republic of Vietnam, is the easternmost country on the Indochina Peninsula in Southeast Asia. With an estimated 92.7 million inhabitants as of 2016, it is the worlds 14th-most-populous country, and its capital city has been Hanoi since the reunification of North and South Vietnam in 1976, with Ho Chi Minh City as a historical city as well. The northern part of Vietnam was part of Imperial China for over a millennium, an independent Vietnamese state was formed in 939, following a Vietnamese victory in the Battle of Bạch Đằng River. Following a Japanese occupation in the 1940s, the Vietnamese fought French rule in the First Indochina War, Vietnam was divided politically into two rival states, North Vietnam, and South Vietnam. Conflict between the two sides intensified in what is known as the Vietnam War, the war ended with a North Vietnamese victory in 1975. Vietnam was unified under a communist government but remained impoverished, in 1986, the government initiated a series of economic and political reforms which began Vietnams path towards integration into the world economy.
By 2000, it had established relations with all nations. Since 2000, Vietnams economic growth rate has been among the highest in the world and its successful economic reforms resulted in its joining the World Trade Organization in 2007. It is a member of the Asia-Pacific Economic Cooperation and the Organisation Internationale de la Francophonie, Vietnam remains one of the worlds four remaining one-party socialist states officially espousing communism. The name Việt Nam is a variation of Nam Việt, a name that can be traced back to the Triệu Dynasty of the 2nd century BC. The word Việt originated as a form of Bách Việt. The form Vietnam is first recorded in the 16th-century oracular poem Sấm Trạng Trình, the name has been found on 12 steles carved in the 16th and 17th centuries, including one at Bao Lam Pagoda in Haiphong that dates to 1558. Then, as recorded, rewarded Yuenan/Vietnam as their nations name, to show that they are below the region of Baiyue/Bach Viet. Between 1804 and 1813, the name was used officially by Emperor Gia Long and it was revived in the early 20th century by Phan Bội Châus History of the Loss of Vietnam, and by the Vietnamese Nationalist Party.
The country was usually called Annam until 1945, when both the government in Huế and the Viet Minh government in Hanoi adopted Việt Nam. Archaeological excavations have revealed the existence of humans in what is now Vietnam as early as the Paleolithic age, Homo erectus fossils dating to around 500,000 BC have been found in caves in Lạng Sơn and Nghệ An provinces in northern Vietnam. The oldest Homo sapiens fossils from mainland Southeast Asia are of Middle Pleistocene provenance, teeth attributed to Homo sapiens from the Late Pleistocene have been found at Dong Can, and from the Early Holocene at Mai Da Dieu, Lang Gao and Lang Cuom. The Hồng Bàng dynasty of the Hùng kings is considered the first Vietnamese state, in 257 BC, the last Hùng king was defeated by Thục Phán, who consolidated the Lạc Việt and Âu Việt tribes to form the Âu Lạc, proclaiming himself An Dương Vương
A stalactite is a type of formation that hangs from the ceiling of caves, hot springs, or manmade structures such as bridges and mines. Any material which is soluble, can be deposited as a colloid, or is in suspension, or is capable of being melted, Stalactites may be composed of amberat, minerals, peat, pitch and sinter. A stalactite is not necessarily a speleothem, though speleothems are the most common form of stalactite because of the abundance of limestone caves, the corresponding formation on the floor of the cave is known as a stalagmite. The most common stalactites are speleothems, which occur in limestone caves and they form through deposition of calcium carbonate and other minerals, which is precipitated from mineralized water solutions. Limestone is the form of calcium carbonate rock which is dissolved by water that contains carbon dioxide. When the solution comes into contact with air the chemical reaction that created it is reversed, the reversed reaction is, Ca 2 → CaCO3 + H 2O + CO2 An average growth rate is 0.13 mm a year.
The quickest growing stalactites are formed by a constant supply of slow dripping water rich in calcium carbonate and carbon dioxide. The drip rate must be enough to allow the CO2 to degas from the solution into the cave atmosphere. Too fast a drip rate and the solution, still carrying most of the CaCO3, falls to the floor where degassing occurs. All limestone stalactites begin with a single drop of water. When the drop falls, it deposits the thinnest ring of calcite, each subsequent drop that forms and falls deposits another calcite ring. Eventually, these form a very narrow, hollow tube commonly known as a soda straw stalactite. Soda straws can grow long, but are very fragile. If they become plugged by debris, water flowing over the outside, depositing more calcite. The same water drops that fall from the tip of a stalactite deposit more calcite on the floor below, unlike stalactites, stalagmites never start out as hollow soda straws. Given enough time, these formations can meet and fuse to create pillars of calcium carbonate known as a column, another type of stalactite is formed in lava tubes while lava is still active inside.
The mechanism of formation is similar to that of limestone stalactites, a key difference with lava stalactites is that once the lava has ceased flowing, so too will the stalactites cease to grow. This means that if the stalactite were to be broken it would never grow back, the generic term lavacicle has been applied to lava stalactites and stalagmites indiscriminately and evolved from the word icicle
The Sasanian Empire was founded by Ardashir I, after the fall of the Parthian Empire and the defeat of the last Arsacid king, Artabanus V. According to a legend, the vexilloid of the Sasanian Empire was the Derafsh Kaviani, in many ways, the Sasanian period witnessed the peak of ancient Iranian civilization. Persia influenced Roman culture considerably during the Sasanian period, the Sasanians cultural influence extended far beyond the empires territorial borders, reaching as far as Western Europe, Africa and India. It played a prominent role in the formation of both European and Asian medieval art, much of what became known as Islamic culture in art, architecture and other subject matter was transferred from the Sasanians throughout the Muslim world. Conflicting accounts shroud the details of the fall of the Parthian Empire, the Sassanid Empire was established in Estakhr by Ardashir I. Papak was originally the ruler of a region called Khir, however, by the year 200, he managed to overthrow Gochihr, and appoint himself as the new ruler of the Bazrangids.
His mother, was the daughter of the governor of Pars. Papak and his eldest son Shapur managed to expand their power all of Pars. The subsequent events are unclear, due to the nature of the sources. It is certain, that following the death of Papak, sources reveal that Shapur, leaving for a meeting with his brother, was killed when the roof of a building collapsed on him. By the year 208, over the protests of his brothers who were put to death. Once Ardashir was appointed shahanshah, he moved his capital further to the south of Pars, the city, well supported by high mountains and easily defendable through narrow passes, became the center of Ardashirs efforts to gain more power. The city was surrounded by a high, circular wall, probably copied from that of Darabgird, in a second attempt to destroy Ardashir, Artabanus V himself met Ardashir in battle at Hormozgan, where Artabanus V met his death. Following the death of the Parthian ruler, Ardashir I went on to invade the provinces of the now defunct Parthian Empire.
Ardashir was aided by the geography of the province of Fars, in the next few years, local rebellions would form around the empire. Nonetheless, Ardashir I further expanded his new empire to the east and northwest, conquering the provinces of Sistan, Khorasan, Balkh and he added Bahrain and Mosul to Sassanids possessions. In the west, assaults against Hatra and Adiabene met with less success, in 230, he raided deep into Roman territory, and a Roman counter-offensive two years ended inconclusively, although the Roman emperor, Alexander Severus, celebrated a triumph in Rome. Ardashir Is son Shapur I continued the expansion of the empire, conquering Bactria, invading Roman Mesopotamia, Shapur I captured Carrhae and Nisibis, but in 243 the Roman general Timesitheus defeated the Persians at Rhesaina and regained the lost territories
A ceiling /ˈsiːlɪŋ/ is an overhead interior surface that covers the upper limits of a room. It is not generally considered an element, but a finished surface concealing the underside of the roof structure or the floor of a storey above. Ceilings can be decorated to taste, and there are fine examples of frescoes. The most common type of ceiling is the ceiling which is suspended from structural elements above. Pipework or ducts can be run in the gap above the ceiling, other types of ceiling include the cathedral ceiling, the concave or barrel-shaped ceiling, the stretched ceiling and the coffered ceiling. Coving often links the ceiling to the surrounding walls, ceilings can play a part in reducing fire hazard, and a system is available for rating the fire resistance of dropped ceilings. Ceilings are classified according to their appearance or construction, a cathedral ceiling is any tall ceiling area similar to those in a church. A dropped ceiling is one in which the surface is constructed anywhere from a few inches or centimetres to several feet or a few metres below the structure above it.
This may be done for aesthetic purposes, such as achieving a desirable ceiling height, an inverse of this would be a raised floor. A cove ceiling uses a curved plaster transition between wall and ceiling, it is named for cove molding, a molding with a concave curve, a stretched ceiling uses a number of individual panels using material such as PVC fixed to a permieter rail. Ceilings have frequently been decorated with painting, mosaic tiles. While hard to execute a decorated ceiling has the advantage that it is protected from damage by fingers. In the past, this was more than compensated for by the damage from smoke from candles or a fireplace, many historic buildings have celebrated ceilings. Perhaps the most famous is the Sistine Chapel ceiling by Michelangelo, ceiling height may have psychological impacts. The most common ceiling that contributes to fire-resistance ratings in commercial and residential construction is the dropped ceiling, an independent ceiling, can be constructed such that it has a stand-alone fire-resistance rating.
Such systems must be tested without the benefit of being suspended from a slab above in order to prove that the system is capable of holding itself up. This type of ceiling would be installed to protect items above from fire, merriam-Webster ceiling definition Diydata. com treatise on lath & plasterboard ceilings Virtualmuseum. ca treatise on ceiling construction
Lava is the molten rock expelled by a volcano during an eruption. The resulting rock after solidification and cooling is called lava. The molten rock is formed in the interior of planets, including Earth. The source of the heat melts the rock within the earth is geothermal energy. When first erupted from a vent, lava is a liquid usually at temperatures from 700 to 1,200 °C. A lava flow is an outpouring of lava, which is created during a non-explosive effusive eruption. When it has stopped moving, lava solidifies to form igneous rock, the term lava flow is commonly shortened to lava. Although lava can be up to 100,000 times more viscous than water, lava can flow great distances before cooling and solidifying because of its thixotropic, explosive eruptions produce a mixture of volcanic ash and other fragments called tephra, rather than lava flows. The word lava comes from Italian, and is derived from the Latin word labes which means a fall or slide. The first use in connection with extruded magma was apparently in an account written by Francesco Serao on the eruption of Vesuvius between May 14 and June 4,1737.
Serao described a flow of lava as an analogy to the flow of water. The composition of almost all lava of the Earths crust is dominated by silicate minerals, mostly feldspars, pyroxenes, micas, igneous rocks, which form lava flows when erupted, can be classified into three chemical types, felsic and mafic. These classes are primarily chemical, the chemistry of lava tends to correlate with the temperature, its viscosity. Felsic or silicic lavas such as rhyolite and dacite typically form lava spines, most silicic lava flows are extremely viscous, and typically fragment as they extrude, producing blocky autobreccias. Felsic magmas can erupt at temperatures as low as 650 to 750 °C, unusually hot rhyolite lavas, may flow for distances of many tens of kilometres, such as in the Snake River Plain of the northwestern United States. Intermediate or andesitic lavas are lower in aluminium and silica, and usually somewhat richer in magnesium, intermediate lavas form andesite domes and block lavas, and may occur on steep composite volcanoes, such as in the Andes.
Poorer in aluminium and silica than felsic lavas, and commonly hotter, greater temperatures tend to destroy polymerized bonds within the magma, promoting more fluid behaviour and a greater tendency to form phenocrysts. Higher iron and magnesium tends to manifest as a darker groundmass, mafic or basaltic lavas are typified by their high ferromagnesian content, and generally erupt at temperatures in excess of 950 °C
Water is a transparent and nearly colorless chemical substance that is the main constituent of Earths streams and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen, Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperature and pressure, but it often refers to its solid state or its gaseous state. It occurs in nature as snow, ice packs and icebergs, fog, aquifers, Water covers 71% of the Earths surface. It is vital for all forms of life. Only 2. 5% of this water is freshwater, and 98. 8% of that water is in ice and groundwater. Less than 0. 3% of all freshwater is in rivers and the atmosphere, a greater quantity of water is found in the earths interior. Water on Earth moves continually through the cycle of evaporation and transpiration, precipitation. Evaporation and transpiration contribute to the precipitation over land, large amounts of water are chemically combined or adsorbed in hydrated minerals.
Safe drinking water is essential to humans and other even though it provides no calories or organic nutrients. There is a correlation between access to safe water and gross domestic product per capita. However, some observers have estimated that by 2025 more than half of the population will be facing water-based vulnerability. A report, issued in November 2009, suggests that by 2030, in developing regions of the world. Water plays an important role in the world economy, approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a source of food for many parts of the world. Much of long-distance trade of commodities and manufactured products is transported by boats through seas, lakes, large quantities of water and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a variety of chemical substances, as such it is widely used in industrial processes. Water is central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, sport fishing, Water is a liquid at the temperatures and pressures that are most adequate for life.
Specifically, at atmospheric pressure of 1 bar, water is a liquid between the temperatures of 273.15 K and 373.15 K
Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths gravity interacts with objects in space, especially the Sun. During one orbit around the Sun, Earth rotates about its axis over 365 times, Earths axis of rotation is tilted, producing seasonal variations on the planets surface. The gravitational interaction between the Earth and Moon causes ocean tides, stabilizes the Earths orientation on its axis, Earths lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earths surface is covered with water, mostly by its oceans, the remaining 29% is land consisting of continents and islands that together have many lakes and other sources of water that contribute to the hydrosphere.
The majority of Earths polar regions are covered in ice, including the Antarctic ice sheet, Earths interior remains active with a solid iron inner core, a liquid outer core that generates the Earths magnetic field, and a convecting mantle that drives plate tectonics. Within the first billion years of Earths history, life appeared in the oceans and began to affect the Earths atmosphere and surface, some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earths distance from the Sun, physical properties, in the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely, over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival. Humans have developed diverse societies and cultures, the world has about 200 sovereign states, the modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most often spelled eorðe.
It has cognates in every Germanic language, and their proto-Germanic root has been reconstructed as *erþō, earth was written in lowercase, and from early Middle English, its definite sense as the globe was expressed as the earth. By early Modern English, many nouns were capitalized, and the became the Earth. More recently, the name is simply given as Earth. House styles now vary, Oxford spelling recognizes the lowercase form as the most common, another convention capitalizes Earth when appearing as a name but writes it in lowercase when preceded by the. It almost always appears in lowercase in colloquial expressions such as what on earth are you doing, the oldest material found in the Solar System is dated to 4. 5672±0.0006 billion years ago. By 4. 54±0.04 Gya the primordial Earth had formed, the formation and evolution of Solar System bodies occurred along with the Sun