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50-789: It is named after finds made by Samuel Hazzledine Warren in a palaeochannel at Clacton-on-Sea in the English county of Essex in 1911. The artifacts found there included flint chopping tools , flint flakes and the tip of a worked wooden shaft, the Clacton Spear . Further examples of the tools have been found at sites including Barnfield Pit and Rickson's Pit, near Swanscombe in Kent and Barnham in Suffolk ; similar industries have been identified across Northern Europe . The Clactonian industry involved striking thick, irregular flakes from

100-626: A Pleistocene palaeochannel and palaeo-floodplain of the Amite River near Denham Springs, Louisiana. Economically important mineral deposits may be hosted in palaeochannels and associated fluvial deposits. The most important of these deposits are syndepositional palaeo-placer deposits containing gold , cassiterite ( tin ore), and platinum group minerals. In addition, diagenetic and postdepositional ores of uranium and iron have been found in palaeochannel fills. Although layers of lignite and other types of coal are sometimes part of

150-525: A core of flint, which was then employed as a chopper . The flakes would have been used as crude knives or scrapers. Unlike the Oldowan tools, some were notched, implying that they were attached to a handle or shaft. Retouch is uncommon and the prominent bulb of percussion on the flakes indicates use of a hammerstone . Although in modern literature the term almost exclusively refers to finds in Britain,

200-525: A fluvial palaeovalley are not always fluvial sediments; often, fluvial palaeovalleys are filled and buried by some combination of fluvial, volcanic , glacial, aeolian , lacustrine , estuarine, or marine deposits. Finally, even when filled largely by fluvial sediments, the channel deposits that fill a palaeochannel comprise only a small fraction of a valley fill, which mainly consists of the deposits of other fluvial environments. Fertile Crescent The Fertile Crescent ( Arabic : الهلال الخصيب )

250-562: A long history of irrigation. Prehistoric seedless figs were discovered at Gilgal I in the Jordan Valley , suggesting that fig trees were being planted some 11,400 years ago. Cereals were already grown in Syria as long as 9,000 years ago. Small cats ( Felis silvestris ) also were domesticated in this region. Also, legumes including peas , lentils and chickpea were domesticated in this region. Domesticated animals include

300-450: A major problem for coal mining because of the drastic decrease in the total tonnage of mineable coal, and disruption to mining techniques. Also, bedding and jointing within strata comprising palaeochannels typically result in hazardous conditions related to unstable highwalls in opencast mines and collapsable roof rock in coal adits . Coarse-grained (sandy) palaeochannels and palaeovalleys have been proposed as reservoirs or conduits for

350-641: A result. Technological advances in the region include the development of agriculture and the use of irrigation , of writing , the wheel , and glass , most emerging first in Mesopotamia . The term "Fertile Crescent" was popularized by archaeologist James Henry Breasted in Outlines of European History (1914) and Ancient Times, A History of the Early World (1916). He wrote: It lies like an army facing south, with one wing stretching along

400-773: A specific avulsion may be either external or internal to a river system and quite varied. Factors external to a river system that might cause an avulsion include fault activity, sea-level rise, or an increase in flood peak discharge. Factors internal to a river system that might cause an avulsion include sediment influx, breakout along animal pathways, and blockage by ice jams, plant growth, log jams, and beaver dams. A variety of techniques have been used to recognize and map palaeochannels. At first, surficial data from aerial photography, soils maps, topographic maps, archaeological surveys and excavations, and field observations were integrated with subsurface data from geological and engineering borings and cores to recognize and map palaeochannels. As

450-624: Is a crescent-shaped region in the Middle East , spanning modern-day Iraq , Israel , Jordan , Lebanon , Palestine , and Syria , together with northern Kuwait , south-eastern Turkey , and western Iran . Some authors also include Cyprus and northern Egypt . The Fertile Crescent is believed to be the first region where settled farming emerged as people started the process of clearance and modification of natural vegetation to grow newly domesticated plants as crops . Early human civilizations such as Sumer in Mesopotamia flourished as

500-462: Is an avulsion in which an existing active channel is appropriated or if an existing abandoned channel is reoccupied. Second, an avulsion by incision is an avulsion in which a new channel is created by the scouring into the floodplain surface as a direct result of the avulsion. Finally, an avulsion by progradation is an avulsion that results in the formation of an extensive deposition and multi-channeled distributive network. Of these types of avulsions only

550-480: Is derived from the combination of two words, palaeo or old , and channel ; i.e., a palaeochannel is an old channel. Palaeochannels may be preserved either as abandoned surface channels on the surface of river floodplains and terraces or infilled and partially or fully buried by younger sediments . The fill of a palaeochannel and its enclosing sedimentary deposits may consist of unconsolidated, semi-consolidated, or well-cemented sedimentary strata depending on

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600-561: Is described as a " flake and core " industry distinguished from the Acheulean from its lack of use of handaxes . The cores were used as choppers . The shapes of the lithic flakes do not follow a standard pattern. While historically the Clactonian industry was thought to have used stone only to create lithic artifacts, recent evidence has been found supporting the use of animal bones as soft hammers for stone knapping . The industry

650-402: Is the most common fluvial process resulting in the formation of palaeochannels. It is the process by which flow diverts out of an established river channel into a new permanent course on the adjacent floodplain. An avulsion can be either a full avulsion, in which all of the discharge is transferred out of the parent channel to a new one, or partial avulsion, in which only a portion of the discharge

700-489: Is transferred to a new one. Only the full avulsion results the formation of a palaeochannel. Partial avulsions result in the formation of anastomosing channels when the divided active channels rejoin downstream and distributary channels when the divided active channels do not rejoin downstream. At least three broadly different types of avulsions, (a) avulsion by annexation; (b) avulsion by incision; and (c) avulsion by progradation, are recognized. First, an avulsion by annexation

750-538: The Basques and Canary Islanders of the same time period, as the studies demonstrate those ancient peoples to be "clearly associated with modern Europeans". Additionally, no evidence from the studies demonstrates Cro-Magnon influence, contrary to former suggestions. The studies further suggest a diffusion of this diverse population away from the Fertile Crescent, with the early migrants moving away from

800-522: The Bronze Age , the region's natural fertility has been greatly extended by irrigation works, upon which much of its agricultural production continues to depend. The last two millennia have seen repeated cycles of decline and recovery as past works have fallen into disrepair through the replacement of states, to be replaced under their successors. Another ongoing problem has been salination —gradual concentration of salt and other minerals in soils with

850-695: The Jordan River . The inner boundary is delimited by the dry climate of the Syrian Desert to the south. Around the outer boundary are the Anatolian and Armenian highlands to the north, the Sahara Desert to the west, Sudan to the south, and the Iranian plateau to the east. As crucial as rivers and marshlands were to the rise of civilization in the Fertile Crescent, they were not

900-525: The Near East —westward into Europe and North Africa , northward to Crimea , and northeastward to Mongolia . They took their agricultural practices with them and interbred with the hunter-gatherers whom they subsequently came in contact with while perpetuating their farming practices. This supports prior genetic and archaeological studies which have all arrived at the same conclusion. Consequently, contemporary in situ peoples absorbed

950-1028: The Tigris–Euphrates river basin , including Sumer , Akkad , Babylonia , Assyria , and the Abbasid Caliphate . It is in this region where the first libraries appeared about 4,500 years ago. The oldest known libraries are found in Nippur (in Sumer) and Ebla (in Syria), both from c.  2500 BCE . Both the Tigris and Euphrates start in the Taurus Mountains of what is modern-day Turkey . Farmers in southern Mesopotamia had to protect their fields from flooding each year. Northern Mesopotamia had sufficient rain to make some farming possible. To protect against flooding they made levees. Since

1000-474: The cattle , sheep , goat , domestic pig , cat , and domestic goose . Mesopotamia Egypt Iran Anatolia The Levant Arabia Cosmology Modern analyses comparing 24 craniofacial measurements reveal a relatively diverse population within the pre- Neolithic , Neolithic and Bronze Age Fertile Crescent, supporting the view that several populations occupied this region during these time periods. Similar arguments do not hold true for

1050-563: The Clactonian producing hominins. It has been suggested by some authors that Clactonian may have originated from populations of hominins in the adjacent Rhineland area, who also did not use handaxes. Some authors have regarded the Clactonian as simply a regional variant of the Acheulean. The Clactonian dates to the early part of the Hoxnian Interglacial (which correlates with the mainland European Holstein interglacial and

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1100-402: The action of tectonics and diagenesis during their geologic history after deposition. The abandonment of an active fluvial channel and the resulting formation of a palaeochannel can be the result of tectonic processes, geomorphologic processes, anthropogenic activities, climatic changes, or a variable and interrelated combination of these factors. The avulsion of an active river or stream

1150-432: The agricultural way of life of those early migrants who ventured out of the Fertile Crescent. This is contrary to the suggestion that the spread of agriculture disseminated out of the Fertile Crescent by way of sharing of knowledge. Instead, the view now supported by a preponderance of evidence is that it occurred by actual migration out of the region, coupled with subsequent interbreeding with indigenous local populations whom

1200-1035: The approximate past hydrologic regime of a palaeochannel and the palaeoclimate associated with it. Such empirical equations also allow the estimation of palaeochannel gradient, meander wavelength, sinuosity, and discharge from a palaeochannel exposed in cross-section in an outcrop. The sediments or sedimentary rocks filling palaeochannels also often contain dateable material, micro- and megafossils, and palaeoenvironmental proxies. Fine-grained palaeochannel fills containing autochthonous vertebrate fossils may, in extremely favourable ccircumstances, contain unabraded, complete skeletons that are important for understanding habitat-specific palaeofaunas and associated palaeoenvironments. Fine-grained palaeochannel fills also frequently contain wood, leaves, and palynomorphs that can be used for geologic dating and understanding palaeoclimatic and other palaeoenvironmental conditions, including past rainfall, temperatures and climates, and prehistoric and historic climate change and global warming . Finally,

1250-603: The avulsion by incision results in the complete abandonment and preservation of a fluvial channel as a palaeochannel. The exact environmental conditions that favour incisional avulsions remain unsettled. However, it is generally agreed that they are promoted by a) rapid aggradation of the main channel and floodplain; b) wide unobstructed floodplain and down-valley drainage; and c) frequently recurring floods of high magnitude. In many floodplains, these conditions and frequent avulsions are correlated with superelevated alluvial ridges and river stages. The event or factor that can trigger

1300-505: The coarse-grained sediments are more electrically resistive than surrounding materials. Also, lidar, more sophisticated remote sensing techniques, digital analysis, including computer modeling, of data were added to the various techniques used to detect and map palaeochannels. Palaeochannels are important to the Earth sciences because the palaeohydrology of the prehistoric rivers that created them can be reconstructed from their morphology, and

1350-551: The eastern shore of the Mediterranean and the other reaching out to the Persian Gulf, while the center has its back against the northern mountains. The end of the western wing is Palestine; Assyria makes up a large part of the center; while the end of the eastern wing is Babylonia. [...] This great semicircle, for lack of a name, may be called the Fertile Crescent. There is no single term for this region in antiquity. At

1400-481: The elephant. Evidence has also been found for the Clactonian butchery of fallow deer ( Dama clactoniana ). Fertile Crescent : Europe : Africa : Siberia : Palaeochannel In the Earth sciences, a palaeochannel , also spelled paleochannel , is a significant length of a river or stream channel which no longer conveys fluvial discharge as part of an active fluvial system. The term palaeochannel

1450-491: The evolution of many "r" type annual plants , which produce more edible seeds than "K" type perennial plants . The region's dramatic variety in elevation gave rise to many species of edible plants for early experiments in cultivation. Most importantly, the Fertile Crescent was home to the eight Neolithic founder crops important in early agriculture (i.e., wild progenitors to emmer wheat , einkorn , barley , flax , chick pea , pea , lentil , bitter vetch ), and four of

1500-460: The five most important species of domesticated animals— cows , goats , sheep , and pigs ; the fifth species, the horse , lived nearby. The Fertile Crescent flora comprises a high percentage of plants that can self-pollinate , but may also be cross-pollinated . These plants, called " selfers ", were one of the geographical advantages of the area because they did not depend on other plants for reproduction. As well as possessing many sites with

1550-436: The global Marine Isotope Stage 11 ), when Britain had a temperate deciduous forest environment and climate similar to that of Britain during the contemporary Holocene period. One of the most important Clactonian sites was found near Ebbsfleet, Kent, where a large straight-tusked elephant ( Palaeoloxodon antiquus ) skeleton was found associated with Clactonian type stone tools, which are suggested to have been used to butcher

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1600-445: The importance of coarse-grained fluvial deposits associated with palaeochannels as sources of groundwater and favoured conveyance of subsurface water became appreciated, geophysical techniques sensing the physical properties of underlying ground and bedrock and groundwater and other fluids contained within them became more important and widely used. For example, palaeochannels can be identified using airborne electromagnetic surveys , as

1650-455: The migrants came in contact with. The studies show also that not all present day Europeans share strong genetic affinities to the Neolithic and Bronze Age inhabitants of the Fertile Crescent; the closest ties to the Fertile Crescent rest with Southern Europeans. The same study further demonstrates all present-day Europeans to be closely related. Linguistically, the Fertile Crescent

1700-565: The only factor. The area is geographically important as the "bridge" between North Africa and Eurasia , which has allowed it to retain a greater amount of biodiversity than either Europe or North Africa , where climate changes during the Ice Age led to repeated extinction events when ecosystems became squeezed against the waters of the Mediterranean Sea . The Saharan pump theory posits that this Middle Eastern land bridge

1750-502: The preferential underground flow of fresh water. When they extend offshore beneath the continental shelf, they may either transfer freshwater offshore beneath the shelf, or act as pathways for saltwater intrusion into onshore aquifers. Smaller palaeochannels and palaeovalleys, which are commonly filled with muddy or clayey sediments can act as aquicludes that retard and act as barriers to the movement of groundwater. Palaeochannels are often confused with palaeovalleys (or paleovalleys ) in

1800-405: The published literature and studies of groundwater and mineral resources. The nomenclature of palaeochannels must reflect their actual physical character, origin, and evolution if their relationship to mineral and groundwater resources is to be properly understood. Thus, it has been recommended that palaeochannel be used for an inactive channel formed by a river; palaeochannel deposits for

1850-473: The rivers Tigris and Euphrates , lies in the east of the Fertile Crescent), also saw the emergence of early complex societies during the succeeding Bronze Age . There is also early evidence from the region for writing and the formation of hierarchical state level societies. This has earned the region the nickname "The cradle of civilization ". From ancient times empires arose and fell in

1900-463: The sedimentary fill of palaeochannels, they are typically too thin and narrow to be economically mined. Also, they actually occur in palaeovalleys, which have been mislabeled as palaeochannels . Typically, when palaeochannels formed, they often partially or totally removed any underlying peat , the precursor to coal. Thus, where present, they are directly associated with areas of thin or missing coal called either wash-outs or coal wants . Wash-outs are

1950-457: The sediments or sedimentary rocks filling palaeochannels often contain dateable material, fossils, and palaeoenvironmental proxies. The data derived from the analysis of their morphology and the fossils and palaeoenvironmental proxies can be used to study changes in regional palaeohydrology, palaeoclimates, and palaeoenvironments over geological and historic time scales. The morphology and distribution of palaeochannels can also be used to reconstruct

2000-408: The sediments that infill a palaeochannel; and palaeovalley for a valley incised by an ancient river. This distinction is important, first because not all valleys and palaeovalleys are fluvial in origin; some of them may be either of glacial or tectonic origin. Other palaeovalleys are buried submarine canyons cut by turbidity currents and mass wasting . Second, even the deposits that fill

2050-819: The skeletal and cultural remains of both pre-modern and early modern humans (e.g., at Tabun and Es Skhul caves), later Pleistocene hunter-gatherers , and Epipalaeolithic semi-sedentary hunter-gatherers (the Natufians ); the Fertile Crescent is most famous for its sites related to the origins of agriculture . The western zone around the Jordan and upper Euphrates rivers gave rise to the first known Neolithic farming settlements (referred to as Pre-Pottery Neolithic A (PPNA)), which date to around 9,000 BCE and includes very ancient sites such as Göbekli Tepe , Chogha Golan , and Jericho (Tell es-Sultan) . This region, alongside Mesopotamia (Greek for "between rivers", between

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2100-476: The term was historically used broadly for finds across much of the Old World. The distinctiveness of the Clactonian industry has been questioned, because its techniques are very similar to those of the Acheulean industry, and the use of handaxes is known in Britain both before (such as at Boxgrove ) and after the Clactonian, with handaxes also suggested to be found at a number of Clactonian sites. The Clactonian

2150-539: The theoretical equilibrium profiles of rivers and streams provide a datum by which to detect and quantify tectonic processes such as faulting, uplift, and subsidence. Examples of the displacement of palaeochannels by active faulting are shown by the lateral movement along the San Andreas fault where it crosses Wallace Creek in central California, and where a fault of the Baton Rouge fault zone vertically offsets

2200-591: The time that Breasted was writing, it roughly corresponded with the territories of the Ottoman Empire ceded to Britain and France in the Sykes–Picot Agreement . Historian Thomas Scheffler has noted that Breasted was following a trend in Western geography to "overwrite the classical geographical distinctions between continents, countries and landscapes with large, abstract spaces", drawing parallels with

2250-428: The types, prehistory, and geometry of tectonic deformation, such as faulting, folding, uplift, and subsidence within an area. Palaeochannels often preserve the form, width, and sinuosity of prehistoric river channels when they were active. This is important in reconstructing prehistoric climate and hydrology because empirical equations developed using data collected from modern rivers and streams can be used to calculate

2300-504: The work of Halford Mackinder , who conceptualised Eurasia as a 'pivot area' surrounded by an 'inner crescent', Alfred Thayer Mahan's Middle East , and Friedrich Naumann's Mitteleuropa . In current usage, the Fertile Crescent includes Israel , Palestine , Iraq , Syria , Lebanon , Egypt , and Jordan , as well as the surrounding portions of Turkey and Iran . In addition to the Tigris and Euphrates , riverwater sources include

2350-882: Was a region of great diversity. Historically, Semitic languages generally prevailed in the modern regions of Iraq , Syria , Jordan , Lebanon , Israel , Palestine , Sinai and the fringes of southeast Turkey and northwest Iran , as well as the Sumerian (a language isolate ) in Iraq, whilst in the mountainous areas to the east and north a number of generally unrelated language isolates were found, including; Elamite , Gutian and Kassite in Iran , and Hattic , Kaskian and Hurro-Urartian in Turkey. The precise affiliation of these, and their date of arrival, remain topics of scholarly discussion. However, given lack of textual evidence for

2400-496: Was extremely important to the modern distribution of Old World flora and fauna , including the spread of humanity . The area has borne the brunt of the tectonic divergence between the African and Arabian plates and the converging Arabian and Eurasian plates, which has made the region a very diverse zone of high snow-covered mountains. The Fertile Crescent had many diverse climates , and major climatic changes encouraged

2450-478: Was far older than the Clactonian. 1950s authors suggested that the Clactonian may have been ancestral to the Acheulean industry in Britain. While some modern authors have supported this assertion, this has been disputed by other authors, who suggest that end of the Clactionian in Britain and the return of the use of handaxes was the result of a migration of a new population of hominins from the continent replacing

2500-527: Was first defined by Samuel Hazzledine Warren in 1926 based on finds at Clacton-on-Sea, England. In the early 20th century, the Clactonian and Acheulean industry were thought to be produced by two different lineages of humans, due to the perceived primitive nature of Clactonian stoneknapping. While some authors in the 1950s connected the Clactonian to the African Oldowan industry, this was later discarded once radiometric dating made it clear that Oldowan

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