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66-530: The seaside area of Makuhari was reclaimed from the sea. The district was constructed in a span of 10 years. Steven Poole, author of Trigger Happy , described it as "Japan's own vision of the future now". Poole added that is a "shrine to techno-optimism" that "looks just like a city out of a video game". Historically, the Shimosa Plateau formed sea cliffs along Tokyo Bay In the Edo period villages appeared in

132-611: A change from low-amplitude glacial cycles with a dominant periodicity of 41,000 years to asymmetric high-amplitude cycles dominated by a periodicity of 100,000 years. However, a 2020 study concluded that ice age terminations might have been influenced by obliquity since the Mid-Pleistocene Transition, which caused stronger summers in the Northern Hemisphere . Glaciation in the Pleistocene

198-574: A deviation from today's annual mean temperature, taken as zero. This sort of graph is based on another isotope ratio versus time. Ratios are converted to a percentage difference from the ratio found in standard mean ocean water (SMOW). The graph in either form appears as a waveform with overtones . One half of a period is a Marine isotopic stage (MIS). It indicates a glacial (below zero) or an interglacial (above zero). Overtones are stadials or interstadials. According to this evidence, Earth experienced 102 MIS stages beginning at about 2.588 Ma BP in

264-421: A few regions had been studied and the names were relatively few. Today the geologists of different nations are taking more of an interest in Pleistocene glaciology. As a consequence, the number of names is expanding rapidly and will continue to expand. Many of the advances and stadials remain unnamed. Also, the terrestrial evidence for some of them has been erased or obscured by larger ones, but evidence remains from

330-569: A small part of the overall economy on the Shimōsa Plateau, the northern and eastern area of the plateau is a large producer of vegetables for the Tokyo Metropolitan Region. The flat, eastern part of the Shimōsa Plateau continues to support rice production. Pleistocene The Pleistocene ( / ˈ p l aɪ s t ə ˌ s iː n , - s t oʊ -/ PLY -stə-seen, -⁠stoh- ; referred to colloquially as

396-578: A team of Russian scientists in collaboration with Princeton University announced that they had brought two female nematodes frozen in permafrost , from around 42,000 years ago, back to life. The two nematodes, at the time, were the oldest confirmed living animals on the planet. The evolution of anatomically modern humans took place during the Pleistocene. At the beginning of the Pleistocene Paranthropus species were still present, as well as early human ancestors, but during

462-463: Is a plateau on the Kantō Plain in central Honshu , Japan . The plateau covers most of northern Chiba Prefecture . The plateau was historically richly agricultural, but in the 20th century the western and central Shimōsa Plateau became one of the major industrial areas of Japan, as well as a large-scale bedroom community of the Tokyo Metropolitan Region. Narita International Airport is located in

528-781: Is estimated that, at maximum glacial extent, 30% of the Earth's surface was covered by ice. In addition, a zone of permafrost stretched southward from the edge of the glacial sheet, a few hundred kilometres in North America , and several hundred in Eurasia . The mean annual temperature at the edge of the ice was −6 °C (21 °F); at the edge of the permafrost, 0 °C (32 °F). Each glacial advance tied up huge volumes of water in continental ice sheets 1,500 to 3,000 metres (4,900–9,800 ft) thick, resulting in temporary sea-level drops of 100 metres (300 ft) or more over

594-459: Is no systematic correspondence between pluvials to glacials, however. Moreover, regional pluvials do not correspond to each other globally. For example, some have used the term "Riss pluvial" in Egyptian contexts. Any coincidence is an accident of regional factors. Only a few of the names for pluvials in restricted regions have been stratigraphically defined. The sum of transient factors acting at

660-604: Is reddish brown, typical of the Kanto Loam layer, while the fields on the east bank near Makuhari Station are a whitish sand color, showing the different characteristics of the fields in the two areas. During the 1960s and 1970s, land was reclaimed along Tokyo Bay including what is now the Makuhari area of Mihama Ward . The area centered on the Hamada River, from the border between Chiba City and Narashino City in

726-592: The Ice Age ) is the geological epoch that lasted from c.  2.58 million to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations . Before a change was finally confirmed in 2009 by the International Union of Geological Sciences , the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of

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792-659: The Alpine ice sheet on the Alps . Scattered domes stretched across Siberia and the Arctic shelf. The northern seas were ice-covered. South of the ice sheets large lakes accumulated because outlets were blocked and the cooler air slowed evaporation. When the Laurentide Ice Sheet retreated, north-central North America was completely covered by Lake Agassiz . Over a hundred basins, now dry or nearly so, were overflowing in

858-529: The ICS timescale, the Pleistocene is divided into four stages or ages , the Gelasian , Calabrian , Chibanian (previously the unofficial "Middle Pleistocene"), and Upper Pleistocene (unofficially the "Tarantian"). In addition to these international subdivisions, various regional subdivisions are often used. In 2009 the International Union of Geological Sciences (IUGS) confirmed a change in time period for

924-657: The Isthmus of Panama , causing a faunal interchange between the two regions and changing ocean circulation patterns, with the onset of glaciation in the Northern Hemisphere occurring around 2.7 million years ago. During the Early Pleistocene (2.58–0.8 Ma), archaic humans of the genus Homo originated in Africa and spread throughout Afro-Eurasia . The end of the Early Pleistocene is marked by

990-677: The Laurentide Ice Sheet . Charles Lyell introduced the term "Pleistocene" in 1839 to describe strata in Sicily that had at least 70% of their molluscan fauna still living today. This distinguished it from the older Pliocene Epoch , which Lyell had originally thought to be the youngest fossil rock layer. He constructed the name "Pleistocene" ('most new' or 'newest') from the Greek πλεῖστος ( pleīstos ) 'most' and καινός ( kainós ( Latinized as cænus ) 'new'). This contrasts with

1056-615: The Mid-Pleistocene Transition , with the cyclicity of glacial cycles changing from 41,000-year cycles to asymmetric 100,000-year cycles, making the climate variation more extreme. The Late Pleistocene witnessed the spread of modern humans outside of Africa as well as the extinction of all other human species. Humans also spread to the Australian continent and the Americas for the first time, co-incident with

1122-662: The Ruwenzori Range in east and central Africa were larger. Glaciers existed in the mountains of Ethiopia and to the west in the Atlas Mountains . In the northern hemisphere, many glaciers fused into one. The Cordilleran Ice Sheet covered the North American northwest; the east was covered by the Laurentide . The Fenno-Scandian ice sheet rested on northern Europe , including much of Great Britain;

1188-477: The last glacial period ended about 10,000 years ago. Over 11 major glacial events have been identified, as well as many minor glacial events. A major glacial event is a general glacial excursion, termed a "glacial." Glacials are separated by "interglacials". During a glacial, the glacier experiences minor advances and retreats. The minor excursion is a "stadial"; times between stadials are "interstadials". These events are defined differently in different regions of

1254-599: The woolly rhinoceros , various giraffids , such as the Sivatherium ; ground sloths , Irish elk , cave lions , cave bears , Gomphotheres , American lions , dire wolves , and short-faced bears , began late in the Pleistocene and continued into the Holocene. Neanderthals also became extinct during this period. At the end of the last ice age, cold-blooded animals, smaller mammals like wood mice , migratory birds, and swifter animals like whitetail deer had replaced

1320-569: The Early Pleistocene Gelasian . Early Pleistocene stages were shallow and frequent. The latest were the most intense and most widely spaced. By convention, stages are numbered from the Holocene, which is MIS1. Glacials receive an even number and interglacials receive an odd number. The first major glacial was MIS2-4 at about 85–11 ka BP. The largest glacials were 2, 6, 12, and 16. The warmest interglacials were 1, 5, 9 and 11. For matching of MIS numbers to named stages, see under

1386-409: The Earth's surface is cyclical: climate, ocean currents and other movements, wind currents, temperature, etc. The waveform response comes from the underlying cyclical motions of the planet, which eventually drag all the transients into harmony with them. The repeated glaciations of the Pleistocene were caused by the same factors. The Mid-Pleistocene Transition , approximately one million years ago, saw

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1452-546: The Ebi River estuary lowland at the center of Funabashi City in the west to the Miyako River estuary lowland near the center of Chiba City in the east. Makuhari Village was formed when Maga Village, centered in the valley of the Hamada River, merged with the villages of Takeshi, Amado, Chosaku, and Mimomi upstream. Makuhari Village cultivated rice paddies in the lowlands of the Hamada River valley and field crops on

1518-479: The North American west. Lake Bonneville , for example, stood where Great Salt Lake now does. In Eurasia, large lakes developed as a result of the runoff from the glaciers. Rivers were larger, had a more copious flow, and were braided . African lakes were fuller, apparently from decreased evaporation. Deserts, on the other hand, were drier and more extensive. Rainfall was lower because of the decreases in oceanic and other evaporation. It has been estimated that during

1584-527: The Pacific Ocean in the city of Sanmu . Lake Teganuma originally occupied a large area to the north of the plateau, but has narrowed in modern times due to being sealed off from the Tone River and land reclamation projects. Teganuma historically covered 10 square kilometres (3.9 sq mi), but after land reclamation now covers 3.7 square kilometres (1.4 sq mi). Lake Inbanuma

1650-434: The Pleistocene to 2.58 Ma, results in the inclusion of all the recent repeated glaciations within the Pleistocene. Radiocarbon dating is considered to be inaccurate beyond around 50,000 years ago. Marine isotope stages (MIS) derived from Oxygen isotopes are often used for giving approximate dates. Pleistocene non-marine sediments are found primarily in fluvial deposits , lakebeds, slope and loess deposits as well as in

1716-496: The Pleistocene's overall climate could be characterised as a continuous El Niño with trade winds in the south Pacific weakening or heading east, warm air rising near Peru , warm water spreading from the west Pacific and the Indian Ocean to the east Pacific, and other El Niño markers. Pleistocene climate was marked by repeated glacial cycles in which continental glaciers pushed to the 40th parallel in some places. It

1782-503: The Pleistocene, changing the start date from 1.806 to 2.588 million years BP, and accepted the base of the Gelasian as the base of the Pleistocene, namely the base of the Monte San Nicola GSSP . The start date has now been rounded down to 2.580 million years BP. The IUGS has yet to approve a type section , Global Boundary Stratotype Section and Point (GSSP), for the upper Pleistocene/Holocene boundary ( i.e.

1848-805: The Pleistocene, the East Antarctic Ice Sheet thinned by at least 500 meters, and that thinning since the Last Glacial Maximum is less than 50 meters and probably started after ca 14 ka. During the 2.5 million years of the Pleistocene, numerous cold phases called glacials ( Quaternary ice age ), or significant advances of continental ice sheets, in Europe and North America, occurred at intervals of approximately 40,000 to 100,000 years. The long glacial periods were separated by more temperate and shorter interglacials which lasted about 10,000–15,000 years. The last cold episode of

1914-411: The Pleistocene, the plates upon which they sit probably having moved no more than 100 km (62 mi) relative to each other since the beginning of the period. In glacial periods, the sea level would drop by up to 120 m (390 ft) lower than today during peak glaciation, exposing large areas of the present continental shelf as dry land. According to Mark Lynas (through collected data),

1980-768: The Shimōsa Group ( 下総層群 , Shimōsa-sōgun ) , a geological group under the Bōsō Peninsula . The Shimōsa Group dates from the Tertiary and Pleistocene periods, and is roughly divided into the Jizodo, Yabu, and Narita formations. The geological group consists primarily of sedimentary layers of loose sand , and secondarily of clay silt and pebbly -sand layers. Above the Shimōsa Group are more recent rich, fertile layers of volcanic ash . The Shimōsa Plateau yields great deposits of fossils, notably molluscan fossils , as

2046-434: The aid for unemployed Shizoku . Those colonies named after development order, such as: During the militarization of northern Chiba Prefecture that began in the early 20th century, the eastern area of the plateau was declared a military zone. The Shimōsa Plateau was a center of the manufacture of war goods, notably of munitions and military aircraft, and saw the construction of numerous military facilities. Shimofusa Air Base

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2112-706: The appearance of Homo sapiens about 300,000 years ago. Artifacts associated with modern human behavior are unambiguously attested starting 40,000–50,000 years ago. According to mitochondrial timing techniques, modern humans migrated from Africa after the Riss glaciation in the Middle Palaeolithic during the Eemian Stage , spreading all over the ice-free world during the late Pleistocene. A 2005 study posits that humans in this migration interbred with archaic human forms already outside of Africa by

2178-527: The articles for those names. Both marine and continental faunas were essentially modern but with many more large land mammals such as Mammoths , Mastodons , Diprotodons , Smilodons , tigers , lions , Aurochs , short-faced bears , giant sloths , species within Gigantopithecus and others. Isolated landmasses such as Australia , Madagascar , New Zealand and islands in the Pacific saw

2244-483: The capital at Edo. The economic development of the Shimōsa Plateau continued after the Meiji restoration of 1868. An extensive rail network was established and replaced the slower canal routes to the capital. Some of undeveloped areas in this plateau, including former ranches of shogunate, turned into military facility of Imperial Japanese Army (Narashinohara), imperial farm (Sanrizuka, Narita), or agricultural colonies,

2310-650: The center of the Shimōsa Plateau. The Shimōsa Plateau covers most of northern Chiba Prefecture . It ranges between 10 metres (33 ft) and 150 metres (490 ft) above sea level . While the Shimōsa Plateau has no set boundaries, it ranges roughly south to north from the Bōsō Hill Range to the lowlands of the Tone River , and east from the Edo River west to the lowlands of Kujūkuri Beach . It runs from Funabashi to Katori . Shimōsa Plateau sits above

2376-525: The central Shimōsa Plateau in the same period. Immediately after World War II, the transportation system of northern Chiba Prefecture was significantly improved. The rail network connecting northern Chiba Prefecture to Tokyo was expanded, allowing the construction of large-scale housing facilities, and northern Chiba Prefecture became a bedroom community of metropolitan Tokyo. The construction of Narita International Airport between 1972 and 1978 resulted in further economic development and population increase on

2442-497: The central Shimōsa Plateau. In contrast to the large-scale economic development of the western and central Shimōsa Plateau, other parts of Chiba Prefecture saw relatively little economic development and ultimately long-term population decline , notably on the eastern Shimōsa Plateau, the Kujūkuri Plain , and entirety of the southern Bōsō Peninsula . The Shimōsa Plateau remains an important economic center of Japan. Compared to

2508-441: The eastern Shimōsa Plateau along Tokyo Bay. Fishing and agricultural areas along the bay were replaced by landfill. The scenery of the eastern plateau went from largely agricultural to a vast area of factory smokestacks and high-rise housing. The development of sprawling port facilities, originally centered on the city of Chiba, culminated in the establishment of Keiyō Industrial Zone . Manufacturing facilities were developed across

2574-618: The entire surface of the Earth. During interglacial times, such as at present, drowned coastlines were common, mitigated by isostatic or other emergent motion of some regions. The effects of glaciation were global. Antarctica was ice-bound throughout the Pleistocene as well as the preceding Pliocene. The Andes were covered in the south by the Patagonian ice cap. There were glaciers in New Zealand and Tasmania . The current decaying glaciers of Mount Kenya , Mount Kilimanjaro , and

2640-782: The evolution of large birds and even reptiles such as the Elephant bird , moa , Haast's eagle , Quinkana , Megalania and Meiolania . The severe climatic changes during the Ice Age had major impacts on the fauna and flora. With each advance of the ice, large areas of the continents became depopulated, and plants and animals retreating southwards in front of the advancing glacier faced tremendous stress. The most severe stress resulted from drastic climatic changes, reduced living space, and curtailed food supply. A major extinction event of large mammals ( megafauna ), which included mammoths , mastodons , saber-toothed cats , glyptodons ,

2706-444: The extinction of most large-bodied animals in these regions. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, with the sea levels being up to 120 metres (390 ft) lower than present at peak glaciation, allowing the connection of Asia and North America via Beringia and the covering of most of northern North America by

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2772-414: The glacial range, which have their own glacial history depending on latitude, terrain and climate. There is a general correspondence between glacials in different regions. Investigators often interchange the names if the glacial geology of a region is in the process of being defined. However, it is generally incorrect to apply the name of a glacial in one region to another. For most of the 20th century, only

2838-450: The historical terminology was established. Corresponding to the terms glacial and interglacial, the terms pluvial and interpluvial are in use (Latin: pluvia , rain). A pluvial is a warmer period of increased rainfall; an interpluvial is of decreased rainfall. Formerly a pluvial was thought to correspond to a glacial in regions not iced, and in some cases it does. Rainfall is cyclical also. Pluvials and interpluvials are widespread. There

2904-445: The immediately preceding Pliocene ("newer", from πλείων ( pleíōn , "more") and kainós ) and the immediately subsequent Holocene ("wholly new" or "entirely new", from ὅλος ( hólos , "whole") and kainós ) epoch , which extends to the present time. The Pleistocene has been dated from 2.580 million (±0.005) to 11,700 years BP with the end date expressed in radiocarbon years as 10,000 carbon-14 years BP. It covers most of

2970-596: The inland transport of marine products from the Pacific Ocean to Edo . During the Edo period the Shimōsa Plateau saw large-scale development of new rice paddies by the Tokugawa shogunate , as well as the further development of horse ranches, specifically the Kogane and Sakura ranches to supply horses to the shogunate. The inland water routes from Chōshi were developed to supply rice, marine products, and vegetables directly to

3036-622: The large amounts of material moved about by glaciers. Less common are cave deposits, travertines and volcanic deposits (lavas, ashes). Pleistocene marine deposits are found primarily in shallow marine basins mostly (but with important exceptions) in areas within a few tens of kilometres of the modern shoreline. In a few geologically active areas such as the Southern California coast, Pleistocene marine deposits may be found at elevations of several hundred metres. The modern continents were essentially at their present positions during

3102-540: The latest period of repeated glaciation , up to and including the Younger Dryas cold spell. The end of the Younger Dryas has been dated to about 9700 BCE (11,700 calendar years BP). The end of the Younger Dryas is the official start of the current Holocene Epoch . Although it is considered an epoch, the Holocene is not significantly different from previous interglacial intervals within the Pleistocene. In

3168-470: The lower Palaeolithic they disappeared, and the only hominin species found in fossilic records is Homo erectus for much of the Pleistocene. Acheulean lithics appear along with Homo erectus , some 1.8 million years ago, replacing the more primitive Oldowan industry used by A. garhi and by the earliest species of Homo . The Middle Paleolithic saw more varied speciation within Homo , including

3234-478: The megafauna and migrated north. Late Pleistocene bighorn sheep were more slender and had longer legs than their descendants today. Scientists believe that the change in predator fauna after the late Pleistocene extinctions resulted in a change of body shape as the species adapted for increased power rather than speed. The extinctions hardly affected Africa but were especially severe in North America where native horses and camels were wiped out. In July 2018,

3300-478: The period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology . The name is a combination of Ancient Greek πλεῖστος ( pleîstos ) 'most' and καινός ( kainós ; Latinized as cænus ) 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by

3366-471: The plateau was originally submerged under water. The Shimōsa Plateau is crossed by several short, shallow rivers and two small lakes. The Kuriyama River (38.8 kilometres (24.1 mi)) flows eastward from the central area of the plateau east of Narita International Airport to the Pacific Ocean . The shorter Kido River (21.5 kilometres (13.4 mi)) similarly flows eastward and empties into

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3432-509: The plateau. The plateau was historically located in Shimōsa Province , after which it was named, and was a productive agricultural area prior to the industrialization of Japan. The area served to produce rice and vegetables as early as the Nara period . Ranches on the Shimōsa Plateau flatlands were developed to raise horses . Additionally, the network of rivers and canals provided for

3498-572: The post-war period, the distribution of economic activity on the plateau has changed. Primary industry accounts for only 5% of economic activity, secondary accounted for 27%, and tertiary 68%. Tertiary industry on the plateau consists of both the service industry serving the densely populated areas of northern Chiba Prefecture, as well as the extensive logistics network connecting the Keiyō Industrial Zone and Narita International Airport with other areas of Japan. While agriculture accounts for

3564-417: The ratio of O to O (two isotopes of oxygen ) by mass (measured by a mass spectrometer ) present in the calcite of oceanic core samples is used as a diagnostic of ancient ocean temperature change and therefore of climate change. Cold oceans are richer in O , which is included in the tests of the microorganisms ( foraminifera ) contributing the calcite. A more recent version of

3630-461: The recent period of repeated glaciations. The name Plio-Pleistocene has, in the past, been used to mean the last ice age. Formerly, the boundary between the two epochs was drawn at the time when the foraminiferal species Hyalinea baltica first appeared in the marine section at La Castella, Calabria, Italy. However, the revised definition of the Quaternary , by pushing back the start date of

3696-407: The sampling process makes use of modern glacial ice cores. Although less rich in O than seawater, the snow that fell on the glacier year by year nevertheless contained O and O in a ratio that depended on the mean annual temperature. Temperature and climate change are cyclical when plotted on a graph of temperature versus time. Temperature coordinates are given in the form of

3762-649: The sole factor responsible for the variations in climate since they explain neither the long-term cooling trend over the Plio-Pleistocene nor the millennial variations in the Greenland Ice Cores known as Dansgaard-Oeschger events and Heinrich events. Milankovitch pacing seems to best explain glaciation events with periodicity of 100,000, 40,000, and 20,000 years. Such a pattern seems to fit the information on climate change found in oxygen isotope cores. In oxygen isotope ratio analysis, variations in

3828-421: The study of cyclical climate changes. The glacials in the following tables show historical usages, are a simplification of a much more complex cycle of variation in climate and terrain, and are generally no longer used. These names have been abandoned in favour of numeric data because many of the correlations were found to be either inexact or incorrect and more than four major glacials have been recognised since

3894-463: The surrounding plateaus. Sand dunes spread between the mouths of the Hamada River and the Hanami River to the east. This area was once known for producing high-quality carrots, most famously the "Makuhari Carrots" brand. Today, only a few fields remain on the plateau on the west bank of the Hamada River and on the sand dunes on the east bank. The soil on the west bank near Makuhari Hongo Station

3960-648: The upper boundary). The proposed section is the North Greenland Ice Core Project ice core 75° 06' N 42° 18' W. The lower boundary of the Pleistocene Series is formally defined magnetostratigraphically as the base of the Matuyama (C2r) chronozone , isotopic stage 103. Above this point there are notable extinctions of the calcareous nannofossils : Discoaster pentaradiatus and Discoaster surculus . The Pleistocene covers

4026-624: The valleys of the small rivers that cut the plateau. From the west, these villages were Yatsu Village, Kuguta Village (at the Kikuta River), Saginuma Village which is now Narashino City, Makuwari Village (at the Hamada River), Kemigawa Village (at the Hanami River), Inage Village, and Kurosuna Village (near present-day Inage just west of Chiba City center). The Makurahi area is bounded by medium-sized alluvial plains, from

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4092-668: The west, to the Hanami River in the east, was originally named the "Makuhari Landfill". Makuharihongo Station on the Japan Railways Sobu Line is located on a plateau just to the west of the lowland area of the Hamada River valley. Makuhari Station is located on a sand dune to the east. At the top of the sand dunes on the south side of Keisei Makuhari Station is the Kon'yo Shrine. Shimosa Plateau The Shimōsa Plateau ( 下総台地 , Shimōsa-daichi )

4158-543: Was a series of glacials and interglacials, stadials and interstadials, mirroring periodic climate changes. The main factor at work in climate cycling is now believed to be Milankovitch cycles . These are periodic variations in regional and planetary solar radiation reaching the Earth caused by several repeating changes in the Earth's motion. The effects of Milankovitch cycles were enhanced by various positive feedbacks related to increases in atmospheric carbon dioxide concentrations and Earth's albedo. Milankovitch cycles cannot be

4224-640: Was constructed in 1945 by the Imperial Japanese Army Air Force on the border of Kashiwa and Kamagaya . Most of the military facilities and industrial areas on the Shimōsa Plateau were destroyed by Allied bombing during World War II. In the period immediately following World War II the plateau remained agricultural. Primary industry , almost entirely agriculture, accounted for 63% of economic activity, secondary accounted for 12%, and tertiary 25%. Post-war industrial planning resulted in large-scale development of coastal areas on

4290-461: Was created by the natural damming of a small valley in the Shimōsa Plateau, and originally covered 21.3 square kilometres (8.2 sq mi). After land reclamation projects, similar to those carried out on Teganuma, it now covers 13.1 square kilometres (5.1 sq mi). Suigo-Tsukuba Quasi-National Park sits to the northeast of the Shimōsa Plateau in Chiba and Ibaraki prefectures. The park

4356-475: Was established on March 3, 1953, and protects natural areas and cultural heritage of, among other areas, the Tone River basin directly to the north of the plateau. Imba-Teganuma Prefectural Natural Park was established to protect Lakes Teganuma and Inbanuma, and is located at the north of the plateau. The Shimōsa Plateau has supported a population since ancient times, as evidenced by the large concentration of Jōmon period kaizuka or shell middens across

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