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110-593: The Marlborough fault system (also known as Marlborough tectonic domain ) is a set of four large dextral strike-slip faults and other related structures in the northern part of the South Island , New Zealand , which transfer displacement between the mainly transform plate boundary of the Alpine fault and the mainly destructive boundary of the Kermadec Trench , and together form the boundary between

220-500: A fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth 's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults . Energy release associated with rapid movement on active faults

330-732: A broad trend of very gradual cooling known as Neoglaciation , which lasted from the end of the HCO to before the Industrial Revolution . From the 10th-14th century, the climate was similar to that of modern times during a period known as the Mediaeval Warm Period (MWP), also known as the Mediaeval Climatic Optimum (MCO). It was found that the warming that is taking place in current years is both more frequent and more spatially homogeneous than what

440-772: A change in plate motions. This new zone in Canterbury has been termed the Porters Pass–Amberley Fault Zone. The new plate vector is significantly oblique to the Alpine Fault, causing an increased amount of convergence. A set of strike-slip faults formed to accommodate this change by taking up most of the strike-slip component. There are four main fault strands, being the Hope, Clarence, Awatere and Wairau faults, although many other smaller faults, of either strike-slip or thrust type are known. The Hope Fault forms

550-405: A fault as oblique requires both dip and strike components to be measurable and significant. Some oblique faults occur within transtensional and transpressional regimes, and others occur where the direction of extension or shortening changes during the deformation but the earlier formed faults remain active. The hade angle is defined as the complement of the dip angle; it is the angle between

660-582: A fault hosting valuable porphyry copper deposits is northern Chile's Domeyko Fault with deposits at Chuquicamata , Collahuasi , El Abra , El Salvador , La Escondida and Potrerillos . Further south in Chile Los Bronces and El Teniente porphyry copper deposit lie each at the intersection of two fault systems. Faults may not always act as conduits to surface. It has been proposed that deep-seated "misoriented" faults may instead be zones where magmas forming porphyry copper stagnate achieving

770-489: A fault plane, where it becomes locked, are called asperities . Stress builds up when a fault is locked, and when it reaches a level that exceeds the strength threshold, the fault ruptures and the accumulated strain energy is released in part as seismic waves , forming an earthquake . Strain occurs accumulatively or instantaneously, depending on the liquid state of the rock; the ductile lower crust and mantle accumulate deformation gradually via shearing , whereas

880-408: A fault's age by studying soil features seen in shallow excavations and geomorphology seen in aerial photographs. Subsurface clues include shears and their relationships to carbonate nodules , eroded clay, and iron oxide mineralization, in the case of older soil, and lack of such signs in the case of younger soil. Radiocarbon dating of organic material buried next to or over a fault shear

990-427: A hanging wall or foot wall where a thrust fault formed along a relatively weak bedding plane is known as a flat and a section where the thrust fault cut upward through the stratigraphic sequence is known as a ramp . Typically, thrust faults move within formations by forming flats and climbing up sections with ramps. This results in the hanging wall flat (or a portion thereof) lying atop the foot wall ramp as shown in

1100-604: A larger effect on the mid-to-low latitudes and mid-to-high latitudes after ~5600 B.P. Human activity through land use changes already by the Mesolithic had major ecological impacts; it was an important influence on Holocene climatic changes, and is believed to be why the Holocene is an atypical interglacial that has not experienced significant cooling over its course. From the start of the Industrial Revolution onwards, large-scale anthropogenic greenhouse gas emissions caused

1210-484: A major fault. Synthetic faults dip in the same direction as the major fault while the antithetic faults dip in the opposite direction. These faults may be accompanied by rollover anticlines (e.g. the Niger Delta Structural Style). All faults have a measurable thickness, made up of deformed rock characteristic of the level in the crust where the faulting happened, of the rock types affected by

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1320-400: A manner that creates multiple listric faults. The fault panes of listric faults can further flatten and evolve into a horizontal or near-horizontal plane, where slip progresses horizontally along a decollement . Extensional decollements can grow to great dimensions and form detachment faults , which are low-angle normal faults with regional tectonic significance. Due to the curvature of

1430-564: A marine transgression occurred in southeastern Africa; in the Lake Lungué basin, this sea level highstand occurred from 740 to 910 AD, or from 1,210 to 1,040 BP, as evidenced by the lake's connection to the Indian Ocean at this time. This transgression was followed by a period of transition that lasted until 590 BP, when the region experienced significant aridification and began to be extensively used by humans for livestock herding. In

1540-650: A more sustainable sedentary lifestyle . This form of lifestyle change allowed humans to develop towns and villages in centralized locations, which gave rise to the world known today. It is believed that the domestication of plants and animals began in the early part of the Holocene in the tropical areas of the planet. Because these areas had warm, moist temperatures, the climate was perfect for effective farming. Culture development and human population change, specifically in South America, has also been linked to spikes in hydroclimate resulting in climate variability in

1650-584: A much wetter climate from 11,400 to 11,100 BP due to intensification of the ISM. Over the Early Holocene, the region was very wet, but during the Middle Holocene from 6,200 to 3,900 BP, aridification occurred, with the subsequent Late Holocene being relatively arid as a whole. Coastal southwestern India experienced a stronger ISM from 9,690 to 7,560 BP, during the HCO. From 3,510 to 2,550 BP, during

1760-535: A near unanimous vote, the rejection of the working group's Anthropocene Epoch proposal for inclusion in the Geologic Time Scale. The Holocene is a geologic epoch that follows directly after the Pleistocene . Continental motions due to plate tectonics are less than a kilometre over a span of only 10,000 years. However, ice melt caused world sea levels to rise about 35 m (115 ft) in

1870-608: A negative excursion in the δ O record lasting 400 years, is the most prominent climatic event occurring in the Holocene Epoch, and may have marked a resurgence of ice cover. It has been suggested that this event was caused by the final drainage of Lake Agassiz , which had been confined by the glaciers, disrupting the thermohaline circulation of the Atlantic . This disruption was the result of an ice dam over Hudson Bay collapsing sending cold lake Agassiz water into

1980-421: A non-vertical fault are known as the hanging wall and footwall . The hanging wall occurs above the fault plane and the footwall occurs below it. This terminology comes from mining: when working a tabular ore body, the miner stood with the footwall under his feet and with the hanging wall above him. These terms are important for distinguishing different dip-slip fault types: reverse faults and normal faults. In

2090-464: A reverse fault, the hanging wall displaces upward, while in a normal fault the hanging wall displaces downward. Distinguishing between these two fault types is important for determining the stress regime of the fault movement. Faults are mainly classified in terms of the angle that the fault plane makes with the Earth's surface, known as the dip , and the direction of slip along the fault plane. Based on

2200-475: A role. Drangajökull, Iceland's northernmost glacier, melted shortly after 9,200 BP. In Northern Germany , the Middle Holocene saw a drastic increase in the amount of raised bogs, most likely related to sea level rise. Although human activity affected geomorphology and landscape evolution in Northern Germany throughout the Holocene, it only became a dominant influence in the last four centuries. In

2310-422: Is a horst . A sequence of grabens and horsts on the surface of the Earth produces a characteristic basin and range topography . Normal faults can evolve into listric faults, with their plane dip being steeper near the surface, then shallower with increased depth, with the fault plane curving into the Earth. They can also form where the hanging wall is absent (such as on a cliff), where the footwall may slump in

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2420-423: Is a zone of folding close to a fault that likely arises from frictional resistance to movement on the fault. The direction and magnitude of heave and throw can be measured only by finding common intersection points on either side of the fault (called a piercing point ). In practice, it is usually only possible to find the slip direction of faults, and an approximation of the heave and throw vector. The two sides of

2530-740: Is an active dextral fault that arises as a splay off the Alpine Fault south of where the Wairau Fault splays off, just south of the Blue Grey River and follows initially to the east its valley. The surface trace terminates to the east just beyond the Chimmney Stream before the Acheron River . There has been more recent upper crustal microseismicity in this fault than in the Clarence Fault to its south. All parts of

2640-544: Is defined by the direction of movement of the ground as would be seen by an observer on the opposite side of the fault. A special class of strike-slip fault is the transform fault when it forms a plate boundary. This class is related to an offset in a spreading center , such as a mid-ocean ridge , or, less common, within continental lithosphere , such as the Dead Sea Transform in the Middle East or

2750-543: Is often critical in distinguishing active from inactive faults. From such relationships, paleoseismologists can estimate the sizes of past earthquakes over the past several hundred years, and develop rough projections of future fault activity. Many ore deposits lie on or are associated with faults. This is because the fractured rock associated with fault zones allow for magma ascent or the circulation of mineral-bearing fluids. Intersections of near-vertical faults are often locations of significant ore deposits. An example of

2860-492: Is particularly clear in the case of detachment faults and major thrust faults . The main types of fault rock include: In geotechnical engineering , a fault often forms a discontinuity that may have a large influence on the mechanical behavior (strength, deformation, etc.) of soil and rock masses in, for example, tunnel , foundation , or slope construction. The level of a fault's activity can be critical for (1) locating buildings, tanks, and pipelines and (2) assessing

2970-425: Is the cause of most earthquakes . Faults may also displace slowly, by aseismic creep . A fault plane is the plane that represents the fracture surface of a fault. A fault trace or fault line is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A fault zone is a cluster of parallel faults. However,

3080-504: Is used for all the seven epochs of the Cenozoic Era. The International Commission on Stratigraphy has defined the Holocene as starting approximately 11,700 years before 2000 CE (11,650 cal years BP , or 9,700 BCE). The Subcommission on Quaternary Stratigraphy (SQS) regards the term 'recent' as an incorrect way of referring to the Holocene, preferring the term 'modern' instead to describe current processes. It also observes that

3190-762: The Alpine Fault in New Zealand. Transform faults are also referred to as "conservative" plate boundaries since the lithosphere is neither created nor destroyed. Dip-slip faults can be either normal (" extensional ") or reverse . The terminology of "normal" and "reverse" comes from coal mining in England, where normal faults are the most common. With the passage of time, a regional reversal between tensional and compressional stresses (or vice-versa) might occur, and faults may be reactivated with their relative block movement inverted in opposite directions to

3300-625: The Australian and Pacific plates . The Marlborough fault system consists of four main dominantly strike-slip fault strands, which together carry almost all of the displacement associated with the plate boundary. Estimates of the rate of current displacement for total strike-slip across the system are between 39 mm (1.5 in)/year to 48 mm (1.9 in)/year. This has meant up to 450 m (1,480 ft) of relative plate motion in less than 14,000 years. Other smaller faults form as splays of these main faults or accommodate deformation of

3410-684: The French Alps , geochemistry and lithium isotope signatures in lake sediments have suggested gradual soil formation from the Last Glacial Period to the Holocene climatic optimum , and this soil development was altered by the settlement of human societies. Early anthropogenic activities such as deforestation and agriculture reinforced soil erosion, which peaked in the Middle Ages at an unprecedented level, marking human forcing as

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3520-552: The International Commission on Stratigraphy (ICS) had a working group to determine whether it should be. In May 2019, members of the working group voted in favour of recognizing the Anthropocene as formal chrono-stratigraphic unit, with stratigraphic signals around the mid-twentieth century CE as its base. The exact criteria was still to be determined, after which the recommendation also had to be approved by

3630-625: The Intertropical Convergence Zone (ITCZ) produced increased monsoon rainfall over North Africa. The lush vegetation of the Sahara brought an increase in pastoralism . The AHP ended around 5,500 BP, after which the Sahara began to dry and become the desert it is today. A stronger East African Monsoon during the Middle Holocene increased precipitation in East Africa and raised lake levels. Around 800 AD, or 1,150 BP,

3740-738: The Kalahari Desert , Holocene climate was overall very stable and environmental change was of low amplitude. Relatively cool conditions have prevailed since 4,000 BP. In the Middle East, the Holocene brought a warmer and wetter climate, in contrast to the preceding cold, dry Younger Dryas . The Early Holocene saw the advent and spread of agriculture in the Fertile Crescent — sheep , goat , cattle , and later pig were domesticated, as well as cereals, like wheat and barley , and legumes —which would later disperse into much of

3850-708: The Llanquihue in Chile and the Otiran in New Zealand. The Holocene can be subdivided into five time intervals, or chronozones , based on climatic fluctuations: Geologists working in different regions are studying sea levels, peat bogs, and ice-core samples, using a variety of methods, with a view toward further verifying and refining the Blytt–Sernander sequence . This is a classification of climatic periods initially defined by plant remains in peat mosses . Though

3960-650: The North Atlantic ocean . Furthermore, studies show that the melting of Lake Agassiz led to sea-level rise which flooded the North American coastal landscape. The basal peat plant was then used to determine the resulting local sea-level rise of 0.20-0.56m in the Mississippi Delta . Subsequent research, however, suggested that the discharge was probably superimposed upon a longer episode of cooler climate lasting up to 600 years and observed that

4070-568: The Tasman Sea between 105 and 60 million years ago and the reverse faults associated with the uplift of the Inland Kaikōura Mountains between 35 million to 25 million years ago due to the start of convergence of the current plate boundary were created. Further analysis shows that the mutual plate movement has been all effectively accommodated in the region itself, over the last 14,000 odd years by ruptures in size, space and time of

4180-581: The Tien Shan , sedimentological evidence from Swan Lake suggests the period between 8,500 and 6,900 BP was relatively warm, with steppe meadow vegetation being predominant. An increase in Cyperaceae from 6,900 to 2,600 BP indicates cooling and humidification of the Tian Shan climate that was interrupted by a warm period between 5,500 and 4,500 BP. After 2,600 BP, an alpine steppe climate prevailed across

4290-601: The seismic shaking and tsunami hazard to infrastructure and people in the vicinity. In California, for example, new building construction has been prohibited directly on or near faults that have moved within the Holocene Epoch (the last 11,700 years) of the Earth's geological history. Also, faults that have shown movement during the Holocene plus Pleistocene Epochs (the last 2.6 million years) may receive consideration, especially for critical structures such as power plants, dams, hospitals, and schools. Geologists assess

4400-535: The sixth mass extinction or Anthropocene extinction , is an ongoing extinction event of species during the present Holocene epoch (with the more recent time sometimes called Anthropocene) as a result of human activity . The included extinctions span numerous families of fungi , plants , and animals , including mammals , birds , reptiles , amphibians , fish and invertebrates . With widespread degradation of highly biodiverse habitats such as coral reefs and rainforests , as well as other areas,

4510-836: The Alpine Fault and may be referred to as the Alpine-Wairau Fault. It takes its name from the Wairau River , which follows the fault trace for most of its length. It has an estimated slip-rate of 0.3–0.5 cm/year (0.12–0.20 in/year). It is closely associated with the Hope Fault and Jordan Thrust at its south-easternmost edge and likely joins with the Clarence Fault to form the Wairarapa Fault offshore in Cook Strait . Before joining with

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4620-537: The Clarence Fault, The offshore segment of the Kekerengu Fault is known as the Needles Fault. In the 7.8 ( M w ) 2016 Kaikōura earthquake major rupture of both the Kekerengu Fault for 27 km (17 mi), with maximum displacement 12.0 m (39.4 ft) ± 0.7 m (2 ft 4 in) and the Needles Fault for 30 km (19 mi)) occurred. The dextral Elliott Fault branches from

4730-484: The Conway-Charwell Fault. The Clarence Fault runs from close to the Alpine Fault to about 10 km (6.2 mi) west of Ward , where it appears to terminate abruptly. A Holocene slip-rate of 0.35–0.5 cm/year (0.14–0.20 in/year) is estimated for this fault. At the surface the displacement appears to be nearly pure horizontal, but continuous uplift of the neighbouring Inner Kaikōura Range over

4840-616: The Earth to warm. Likewise, climatic changes have induced substantial changes in human civilisation over the course of the Holocene. During the transition from the last glacial to the Holocene, the Huelmo–Mascardi Cold Reversal in the Southern Hemisphere began before the Younger Dryas, and the maximum warmth flowed south to north from 11,000 to 7,000 years ago. It appears that this was influenced by

4950-590: The Holocene Epoch. A 1,500-year cycle corresponding to the North Atlantic oceanic circulation may have had widespread global distribution in the Late Holocene. From 8,500 BP to 6,700 BP, North Atlantic climate oscillations were highly irregular and erratic because of perturbations from substantial ice discharge into the ocean from the collapsing Laurentide Ice Sheet. The Greenland ice core records indicate that climate changes became more regional and had

5060-474: The Holocene has shown significant variability despite ice core records from Greenland suggesting a more stable climate following the preceding ice age. Marine chemical fluxes during the Holocene were lower than during the Younger Dryas, but were still considerable enough to imply notable changes in the climate. The temporal and spatial extent of climate change during the Holocene is an area of considerable uncertainty, with radiative forcing recently proposed to be

5170-480: The Holocene, however, the domestication of plants and animals allowed humans to develop villages and towns in centralized locations. Archaeological data shows that between 10,000 and 7,000 BP rapid domestication of plants and animals took place in tropical and subtropical parts of Asia , Africa , and Central America . The development of farming allowed humans to transition away from hunter-gatherer nomadic cultures, which did not establish permanent settlements, to

5280-540: The Hope Fault. It did not undergo significant rupture in the 2016 Kaikōura earthquake although there was minor motion on its seaward aspects, and some off fault uplift to its south except near the Northern Canterbury domain Conway-Charwell Fault which is parallel, and did rupture only a few hundreds of metres away. After the main shock sequence there were aftershocks clustered to its south in the region of

5390-540: The Jordan Thrust south east to Waipapa Bay where it historically was known to have a deep southeast plunge suggesting past dextral motion. In the 7.8 ( M w ) 2016 Kaikōura earthquake it had a sinistral component however and aftershocks grouped along its length and towards Kaikōura . The size of the displacements were marked and second only to those along the Kekerengu Fault in this earthquake. There

5500-597: The Kekerengu and Clarence faults northwest of Clarence . It trends northeast–southwest ( at about 210°) with displacement in this earthquake being mainly right lateral and it may lie within the hanging wall of a deeper fault structure. This is an active dextral fault between the Clarence and Awatere faults. It had a 4.8 ± 1.2 m dextral displacement in the 1848 Marlborough earthquake of the Awatere Fault . This

5610-437: The Late Holocene, the ISM became weaker, although this weakening was interrupted by an interval of unusually high ISM strength from 3,400 to 3,200 BP. Southwestern China experienced long-term warming during the Early Holocene up until ~7,000 BP. Northern China experienced an abrupt aridification event approximately 4,000 BP. From around 3,500 to 3,000 BP, northeastern China underwent a prolonged cooling, manifesting itself with

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5720-476: The Late Holocene. Animal and plant life have not evolved much during the relatively short Holocene, but there have been major shifts in the richness and abundance of plants and animals. A number of large animals including mammoths and mastodons , saber-toothed cats like Smilodon and Homotherium , and giant sloths went extinct in the late Pleistocene and early Holocene. These extinctions can be mostly attributed to people. In America, it coincided with

5830-460: The Marlborough fault system are currently seismically active. Historical earthquakes (since European settlement) have occurred on both the Hope and Awatere Faults and on the smaller Poulter Fault. Studies of the geomorphology and the use of trenching across fault strands, has identified many earthquakes that occurred during the Holocene on many parts of the fault system. The Hope Fault, which has

5940-458: The Middle Holocene was notable for its warmth, with rhythmic temperature fluctuations every 400-500 and 1,000 years. Before 7,500 BP, the Gulf of Thailand was exposed above sea level and was very arid. A marine transgression occurred from 7,500 to 6,200 BP amidst global warming. During the Middle Holocene, western North America was drier than present, with wetter winters and drier summers. After

6050-642: The Middle to Late Holocene, the coastline of the Levant and Persian Gulf receded, prompting a shift in human settlement patterns following this marine regression. Central Asia experienced glacial-like temperatures until about 8,000 BP, when the Laurentide Ice Sheet collapsed. In Xinjiang , long-term Holocene warming increased meltwater supply during summers, creating large lakes and oases at low altitudes and inducing enhanced moisture recycling. In

6160-411: The Northern Canterbury domain. It appears from the latest studies of the rupture complexity of the 2016 Kaikōura earthquake that the myriad of faults associated with deformation episodes over the past 100 million years are important to propagation of rupture in large events in the southern part of the Marlborough fault system as due to their reorientation they act as reactivated interconnections between

6270-632: The Seaward Segment of the Hope Fault. It ruptured during the 7.8 ( M w ) 2016 Kaikōura earthquake with a component of dextral-normal displacement in contrast to its long-term reverse motion. This also resulted in major uplift to its coastal south east side as it approached the Papatea Fault. The dextral Fidget Fault commences to the south of the Waiau Toa / Clarence River and runs along its valley initially before striking east to

6380-524: The arrival of the Clovis people; this culture was known for " Clovis points " which were fashioned on spears for hunting animals. Shrubs, herbs, and mosses had also changed in relative abundance from the Pleistocene to Holocene, identified by permafrost core samples. Throughout the world, ecosystems in cooler climates that were previously regional have been isolated in higher altitude ecological "islands". The 8.2-ka event , an abrupt cold spell recorded as

6490-403: The brittle upper crust reacts by fracture – instantaneous stress release – resulting in motion along the fault. A fault in ductile rocks can also release instantaneously when the strain rate is too great. Slip is defined as the relative movement of geological features present on either side of a fault plane. A fault's sense of slip is defined as the relative motion of the rock on each side of

6600-473: The central portion of the Clarence Fault and then rejoins it. The Acheron and Dillon sinsteral faults also connect these two faults. The Kelly Fault forms a major fork of the Hope Fault from just west of Harper Pass; it forks again to the west into the Newton and Hura faults just before connecting to the Alpine Fault. The Jordan Thrust is a reverse fault that connects the southern end of the Kekerengu Fault to

6710-484: The climate, Greenlandian (11,700 years ago to 8,200 years ago), Northgrippian (8,200 years ago to 4,200 years ago) and Meghalayan (4,200 years ago to the present), as proposed by International Commission on Stratigraphy . The oldest age, the Greenlandian, was characterized by a warming following the preceding ice age. The Northgrippian Age is known for vast cooling due to a disruption in ocean circulations that

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6820-521: The crust between them, such as the Newton and Hura Faults at the western end of the Hope Fault and the Jordan Thrust that formed the Seaward Kaikōura Range . The dextral strike-slip across this zone has also involved clockwise rotation of the intervening fault blocks of about 20° since the early Pliocene . The Hope Fault is the southern limit of the Marlborough fault system and faults to the south of it, even quite close by, are regarded as part of

6930-460: The current major now dominant strike-slip faults. Retrospective studies of the other large historic events in the Marlborough fault system show that this is not typical in the northeast or central parts of the system. Such faults might include implicate reverse faults from a Gondwana subduction zone before 100 million years ago, but more definitely appear to relate to both low and high angle normal faults associated with Gondwana breakup and opening of

7040-436: The direction of slip, faults can be categorized as: In a strike-slip fault (also known as a wrench fault , tear fault or transcurrent fault ), the fault surface (plane) is usually near vertical, and the footwall moves laterally either left or right with very little vertical motion. Strike-slip faults with left-lateral motion are also known as sinistral faults and those with right-lateral motion as dextral faults. Each

7150-454: The disruption of Bronze Age civilisations in the region. Eastern and southern China, the monsoonal regions of China, were wetter than present in the Early and Middle Holocene. Lake Huguangyan's TOC, δ C wax , δ C org , δ N values suggest the period of peak moisture lasted from 9,200 to 1,800 BP and was attributable to a strong East Asian Summer Monsoon (EASM). Late Holocene cooling events in

7260-473: The early part of the Holocene and another 30 m in the later part of the Holocene. In addition, many areas above about 40 degrees north latitude had been depressed by the weight of the Pleistocene glaciers and rose as much as 180 m (590 ft) due to post-glacial rebound over the late Pleistocene and Holocene, and are still rising today. The sea-level rise and temporary land depression allowed temporary marine incursions into areas that are now far from

7370-427: The end of the last strong phase. Ice core measurements imply that the sea surface temperature (SST) gradient east of New Zealand, across the subtropical front (STF), was around 2 degrees Celsius during the HCO. This temperature gradient is significantly less than modern times, which is around 6 degrees Celsius. A study utilizing five SST proxies from 37°S to 60°S latitude confirmed that the strong temperature gradient

7480-617: The end of the thermal maximum of the HCO around 4,500 BP, the East Greenland Current underwent strengthening. A massive megadrought occurred from 2,800 to 1,850 BP in the Great Basin . Eastern North America underwent abrupt warming and humidification around 10,500 BP and then declined from 9,300 to 9,100 BP. The region has undergone a long term wettening since 5,500 BP occasionally interrupted by intervals of high aridity. A major cool event lasting from 5,500 to 4,700 BP

7590-424: The extent of the area affected was unclear. The beginning of the Holocene corresponds with the beginning of the Mesolithic age in most of Europe . In regions such as the Middle East and Anatolia , the term Epipaleolithic is preferred in place of Mesolithic, as they refer to approximately the same time period. Cultures in this period include Hamburgian , Federmesser , and the Natufian culture , during which

7700-451: The fastest slip rate is characterised by the shortest recurrence interval. The complexity of the 7.8 M w 2016 Kaikōura earthquake completely redefined the understanding of the dynamics of the seismicity in the southern section of the fault system. As the recent movements of all the main faults is now understood, future forecasting of major earthquakes in the area may improve. Fault (geology)#Strike-slip faults In geology ,

7810-456: The fault and of the presence and nature of any mineralising fluids . Fault rocks are classified by their textures and the implied mechanism of deformation. A fault that passes through different levels of the lithosphere will have many different types of fault rock developed along its surface. Continued dip-slip displacement tends to juxtapose fault rocks characteristic of different crustal levels, with varying degrees of overprinting. This effect

7920-402: The fault concerning the other side. In measuring the horizontal or vertical separation, the throw of the fault is the vertical component of the separation and the heave of the fault is the horizontal component, as in "Throw up and heave out". The vector of slip can be qualitatively assessed by studying any drag folding of strata, which may be visible on either side of the fault. Drag folding

8030-576: The fault plane and a vertical plane that strikes parallel to the fault. Ring faults , also known as caldera faults , are faults that occur within collapsed volcanic calderas and the sites of bolide strikes, such as the Chesapeake Bay impact crater . Ring faults are the result of a series of overlapping normal faults, forming a circular outline. Fractures created by ring faults may be filled by ring dikes . Synthetic and antithetic are terms used to describe minor faults associated with

8140-401: The fault plane, the horizontal extensional displacement on a listric fault implies a geometric "gap" between the hanging and footwalls of the fault forms when the slip motion occurs. To accommodate into the geometric gap, and depending on its rheology , the hanging wall might fold and slide downwards into the gap and produce rollover folding , or break into further faults and blocks which fil in

8250-427: The fault-bend fold diagram. Thrust faults form nappes and klippen in the large thrust belts. Subduction zones are a special class of thrusts that form the largest faults on Earth and give rise to the largest earthquakes. A fault which has a component of dip-slip and a component of strike-slip is termed an oblique-slip fault . Nearly all faults have some component of both dip-slip and strike-slip; hence, defining

8360-580: The fault. It is formed of two main segments; the Molesworth section to the southwest and the Eastern section to the northeast. The estimated recent slip-rate for the Molesworth section is 0.44 cm/year (0.17 in/year). It takes its name from the Awatere River whose valley follows the fault trace along some of its length. The Wairau Fault is sometimes regarded as a direct continuation of

8470-481: The four main fault strands. Modelling the measured Hope , Clarence , Awatere and Wairau fault displacements show that they keep up, over periods of less than a 1000 years and a few tens of metres with the plate movement. This was the first proof of a common assumption that had been made by some seismologists of the processes in tectonic related earthquake systems, as opposed to individual faults. An ancestral fault system formed between 25 and 8 million years ago with

8580-478: The full development of the Hikurangi subduction margin which was associated with marked vertical axis rotations. There was progressive development of the modern Marlborough fault system after this from the north towards the south during the early Pliocene , with the Hope Fault complex forming no more than 2 million years ago and current formation to the south of the Hope Fault of a new fault complex, in response to

8690-475: The gap. If faults form, imbrication fans or domino faulting may form. A reverse fault is the opposite of a normal fault—the hanging wall moves up relative to the footwall. Reverse faults indicate compressive shortening of the crust. A thrust fault has the same sense of motion as a reverse fault, but with the dip of the fault plane at less than 45°. Thrust faults typically form ramps, flats and fault-bend (hanging wall and footwall) folds. A section of

8800-481: The last glacial period and then classify climates of more recent prehistory . Paleontologists have not defined any faunal stages for the Holocene. If subdivision is necessary, periods of human technological development, such as the Mesolithic , Neolithic , and Bronze Age , are usually used. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of

8910-411: The method was once thought to be of little interest, based on C dating of peats that was inconsistent with the claimed chronozones, investigators have found a general correspondence across Eurasia and North America . The scheme was defined for Northern Europe , but the climate changes were claimed to occur more widely. The periods of the scheme include a few of the final pre-Holocene oscillations of

9020-531: The mid-19th century. The LIA was the coldest interval of time of the past two millennia. Following the Industrial Revolution, warm decadal intervals became more common relative to before as a consequence of anthropogenic greenhouse gases, resulting in progressive global warming. In the late 20th century, anthropogenic forcing superseded variations in solar activity as the dominant driver of climate change, though solar activity has continued to play

9130-717: The mid-Holocene (8.2 - 4.2 k cal BP). Climate change on seasonality and available moisture also allowed for favorable agricultural conditions which promoted human development for Maya and Tiwanaku regions. In the Korean Peninsula , climatic changes fostered a population boom during the Middle Chulmun period from 5,500 to 5,000 BP, but contributed to a subsequent bust during the Late and Final Chulmun periods, from 5,000 to 4,000 BP and from 4,000 to 3,500 BP respectively. The Holocene extinction , otherwise referred to as

9240-586: The most powerful factor affecting surface processes. The sedimentary record from Aitoliko Lagoon indicates that wet winters locally predominated from 210 to 160 BP, followed by dry winter dominance from 160 to 20 BP. North Africa, dominated by the Sahara Desert in the present, was instead a savanna dotted with large lakes during the Early and Middle Holocene, regionally known as the African Humid Period (AHP). The northward migration of

9350-526: The oldest inhabited places still existing on Earth were first settled, such as Tell es-Sultan (Jericho) in the Middle East . There is also evolving archeological evidence of proto-religion at locations such as Göbekli Tepe , as long ago as the 9th millennium BC . The preceding period of the Late Pleistocene had already brought advancements such as the bow and arrow , creating more efficient forms of hunting and replacing spear throwers . In

9460-539: The origin of cycles identified in the North Atlantic region. Climate cyclicity through the Holocene ( Bond events ) has been observed in or near marine settings and is strongly controlled by glacial input to the North Atlantic. Periodicities of ≈2500, ≈1500, and ≈1000 years are generally observed in the North Atlantic. At the same time spectral analyses of the continental record, which is remote from oceanic influence, reveal persistent periodicities of 1,000 and 500 years that may correspond to solar activity variations during

9570-500: The original movement (fault inversion). In such a way, a normal fault may therefore become a reverse fault and vice versa. In a normal fault, the hanging wall moves downward, relative to the footwall. The dip of most normal faults is at least 60 degrees but some normal faults dip at less than 45 degrees. A downthrown block between two normal faults dipping towards each other is a graben . A block stranded between two grabens, and therefore two normal faults dipping away from each other,

9680-566: The period exceeds any likely tectonic uplift of non-glacial origin. Post-glacial rebound in the Scandinavia region resulted in a shrinking Baltic Sea . The region continues to rise, still causing weak earthquakes across Northern Europe. An equivalent event in North America was the rebound of Hudson Bay , as it shrank from its larger, immediate post-glacial Tyrrell Sea phase, to its present boundaries. The climate throughout

9790-492: The present. The human impact on modern-era Earth and its ecosystems may be considered of global significance for the future evolution of living species, including approximately synchronous lithospheric evidence, or more recently hydrospheric and atmospheric evidence of the human impact. In July 2018, the International Union of Geological Sciences split the Holocene Epoch into three distinct ages based on

9900-507: The region were dominantly influenced by solar forcing, with many individual cold snaps linked to solar minima such as the Oort, Wolf , Spörer , and Maunder Minima . A notable cooling event in southeastern China occurred 3,200 BP. Strengthening of the winter monsoon occurred around 5,500, 4,000, and 2,500 BP. Monsoonal regions of China became more arid in the Late Holocene. In the Sea of Japan,

10010-612: The region. Sand dune evolution in the Bayanbulak Basin shows that the region was very dry from the Holocene's beginning until around 6,500 BP, when a wet interval began. In the Tibetan Plateau, the moisture optimum spanned from around 7,500 to 5,500 BP. The Tarim Basin records the onset of significant aridification around 3,000-2,000 BP. After 11,800 BP, and especially between 10,800 and 9,200 BP, Ladakh experienced tremendous moisture increase most likely related to

10120-656: The residual glacial ice remaining in the Northern Hemisphere until the later date. The first major phase of Holocene climate was the Preboreal . At the start of the Preboreal occurred the Preboreal Oscillation (PBO). The Holocene Climatic Optimum (HCO) was a period of warming throughout the globe but was not globally synchronous and uniform. Following the HCO, the global climate entered

10230-412: The right time for—and type of— igneous differentiation . At a given time differentiated magmas would burst violently out of the fault-traps and head to shallower places in the crust where porphyry copper deposits would be formed. As faults are zones of weakness, they facilitate the interaction of water with the surrounding rock and enhance chemical weathering . The enhanced chemical weathering increases

10340-416: The same period, suggests that some of the dip-slip component thought to be present at depth on the fault zone is transferred onto thrust or reverse faults under the range. An extra 10° of clockwise rotation has been recognised within the block that lies northeast of the tip of the Clarence fault. It takes its name from the Waiau Toa / Clarence River , which follows the fault trace in the northeastern section of

10450-400: The sea. For example, marine fossils from the Holocene epoch have been found in locations such as Vermont and Michigan . Other than higher-latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain , and cave deposits. Holocene marine deposits along low-latitude coastlines are rare because the rise in sea levels during

10560-572: The size of the weathered zone and hence creates more space for groundwater . Fault zones act as aquifers and also assist groundwater transport. Holocene The Holocene correlates with the last maximum axial tilt of the Earth towards the Sun, and corresponds with the rapid proliferation, growth, and impacts of the human species worldwide, including all of its written history , technological revolutions , development of major civilizations , and overall significant transition towards urban living in

10670-481: The south of the hill of Mackintosh Knob and intercepting the Jordan Thrust near the coast where the Jordan Thrust transitions to the Kekerengu Fault. Its eastern portion ruptured in the 2016 Kaikōura earthquake with some increased vertical displacement upwards to its north in the Seaward Kaikōura Range. After the 2016 Kaikōura earthquake there was an aftershock cluster to its south. The Papatea Fault runs from

10780-544: The southernmost part of the Marlborough fault system. The estimated slip-rate during the Holocene is 0.2–0.25 cm/year (0.079–0.098 in/year), just over half of the plate boundary displacement. At its northeastern end it links into the Jordan Thrust and most of the displacement is transferred onto that structure. It takes its name from the Hope River , which runs along one of the central fault segments. The Kekerengu Fault and Jordan Thrust are closely associated with

10890-749: The strengthening of the Indian Summer Monsoon (ISM). From 9,200 to 6,900 BP, relative aridity persisted in Ladakh. A second major humid phase occurred in Ladakh from 6,900 to 4,800 BP, after which the region was again arid. From 900 to 1,200 AD, during the MWP, the ISM was again strong as evidenced by low δ O values from the Ganga Plain. The sediments of Lonar Lake in Maharashtra record dry conditions around 11,400 BP that transitioned into

11000-818: The term 'Flandrian' may be used as a synonym for Holocene, although it is becoming outdated. The International Commission on Stratigraphy, however, considers the Holocene to be an epoch following the Pleistocene and specifically following the last glacial period . Local names for the last glacial period include the Wisconsinan in North America , the Weichselian in Europe, the Devensian in Britain,

11110-468: The term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the distinction, as the rock between the faults is converted to fault-bound lenses of rock and then progressively crushed. Due to friction and the rigidity of the constituent rocks, the two sides of a fault cannot always glide or flow past each other easily, and so occasionally all movement stops. The regions of higher friction along

11220-610: The working group's parent bodies (ultimately the International Union of Geological Sciences ). In March 2024, after 15 years of deliberation, the Anthropocene Epoch proposal of the working group was voted down by a wide margin by the SQS, owing largely to its shallow sedimentary record and extremely recent proposed start date. The ICS and the International Union of Geological Sciences later formally confirmed, by

11330-590: The world. Some scholars have argued that a third epoch of the Quaternary, the Anthropocene , has now begun. This term has been used to denote the present time-interval in which many geologically significant conditions and processes have been profoundly altered by human activities. The 'Anthropocene' (a term coined by Paul J. Crutzen and Eugene Stoermer in 2000) was never a formally defined geological unit. The Subcommission on Quaternary Stratigraphy (SQS) of

11440-577: The world. This ' Neolithic Revolution ', likely influenced by Holocene climatic changes, included an increase in sedentism and population, eventually resulting in the world's first large-scale state societies in Mesopotamia and Egypt . During the Middle Holocene, the Intertropical Convergence Zone , which governs the incursion of monsoon precipitation through the Arabian Peninsula, shifted southwards, resulting in increased aridity. In

11550-417: Was around 2.1 metres above present and occurred about 5,800 to 5,000 BP. Sea levels at Rocas Atoll were likewise higher than present for much of the Late Holocene. The Northwest Australian Summer Monsoon was in a strong phase from 8,500 to 6,400 BP, from 5,000 to 4,000 BP (possibly until 3,000 BP), and from 1,300 to 900 BP, with weak phases in between and the current weak phase beginning around 900 BP after

11660-477: Was caused by the melting of glaciers. The most recent age of the Holocene is the present Meghalayan, which began with extreme drought that lasted around 200 years. The word Holocene was formed from two Ancient Greek words. Hólos ( ὅλος ) is the Greek word for "whole". "Cene" comes from the Greek word kainós ( καινός ), meaning "new". The concept is that this epoch is "entirely new". The suffix '-cene'

11770-524: Was coeval with a major humidification before being terminated by a major drought and warming at the end of that interval. During the Early Holocene, relative sea level rose in the Bahia region, causing a landward expansion of mangroves. During the Late Holocene, the mangroves declined as sea level dropped and freshwater supply increased. In the Santa Catarina region, the maximum sea level highstand

11880-603: Was confined to the area immediately south of the STF, and is correlated with reduced westerly winds near New Zealand. Since 7,100 BP, New Zealand experienced 53 cyclones similar in magnitude to Cyclone Bola . Evidence from the Galápagos Islands shows that the El Niño–Southern Oscillation (ENSO) was significantly weaker during the Middle Holocene, but that the strength of ENSO became moderate to high over

11990-467: Was experienced during the MWP. A warming of +1 degree Celsius occurs 5–40 times more frequently in modern years than during the MWP. The major forcing during the MWP was due to greater solar activity, which led to heterogeneity compared to the greenhouse gas forcing of modern years that leads to more homogeneous warming. This was followed by the Little Ice Age (LIA) from the 13th or 14th century to

12100-423: Was up to 7.3 m (24 ft) of left-lateral displacement and 9 m (30 ft) of west side up vertical slip. The Snowgrass Creek Fault was identified to be an active subsurface fault zone by optical displacement analysis (any surface rupture might be difficult to recognise due to mountainous location) and was associated with a prominent group of aftershocks after 2016 Kaikoura earthquake. It extends between

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