Saturday 30 September 2023

Evidence for the construction of wooden structures in the Middle Pleistocene of Zambia.

The first evidence of woodworking is associated with the Early Pleistocene of Oldowan Culture of East Africa, with a number of stone tools showing wear traces and residues left when they were used to work wood. The earliest known wooden tools come from the Middle Pleistocene of Southern Africa, with waterlogged wooden items from several sites, associated with Middle Stone Age and Acheulean stone tools. One such site is at Kalambo Falls in northern Zambia, where a series of wooden artefacts were recovered in the 1950s and 1960s, from horizons which also produced Acheulean tools. These included a wood chip, and three objects with transverse notches interpreted to have been made by intentional shaping of the wood. The Amanzi Springs site in Eastern Cape Province, South Africa, a stick with a possible chop mark was discovered in a waterlogged deposit which also produced Acheulean tools in the 1960s. These deposits were radiometrically dated to between 404 000 and 390 000 years before the present, from unmodified wood within the same strata. A wooden object with cut marks and fine striations from the Florisbad Spring Deposit in Free State, South Africa, was found alongside Middle Stone Age stone tools and remains of the Hominin Homo helmei; this is considered to be the oldest known clearly modified wooden object, but has not been dated beyond Middle Pleistocene.

In a paper published in the journal Nature on 20 September 2023, Larry Barham of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, Geoff Duller of the Department of Geography and Earth Sciences at Aberystwyth University, Ian Candy of the Department of Geography at Royal Holloway, University of London, Christopher Scott, also of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, Caroline Cartwright of the Department of Scientific Research at the British Museum, John Peterson again of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, Ceren Kabukcu, again of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, and of the Interdisciplinary Center for Archaeology and Evolution of Human Behaviour at the University of Algarve, Melisa Chapot, also of the Department of Geography and Earth Sciences at Aberystwyth University, F Melia, again of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, Veerle Rots of the Prehistory TraceoLab  at the University of Liège, Nikki George, again of the Department of Archaeology, Classics & Egyptology at the University of Liverpool, Noora Taipale, also of the Prehistory TraceoLab at the University of Liège, Peter Gethin, once again of the  Department of Archaeology, Classics & Egyptology at the University of Liverpool, and Perrice Nkombwe of the Moto Moto Museum describe recently described evidence for wood being used tob build a structure in the Middle Pleistocene at Kalambo Falls.

New excavations at Kalambo Falls in 2019 recovered five modified wooden artefacts from four different areas, at different layers within the sediments, both above and below the current level of the river. A sixth wooden object showed no signs of intentional modification, but was associated with one of the modified wooden items and some Acheulian stone tools, in a layer below the current river level. One of the other modified wooden objects was also found (separately) associated with Acheulian stone tools, in a layer below the current river level. The remaining modified wooden objects were found without associated stone tools in layers above the current river level, two of them together and one on its own. 

Location of Kalambo Falls archaeological site and excavated areas. (a) Site location in south-central Africa. (b) Course of the Kalambo River (in outline) from around 1956 to 2006 in relation to previous excavations at sites A, B, C, D and C North. Site BLB (2019) and excavation units BLB1, BLB2, BLB3, BLB4 and BLB5 are located along the current main channel (blue). (c) Cross-section of the 2019 excavation units showing the location of 16 luminescence dating samples (KF01–KF17, dark blue circles, uncertainties (±) shown at 1 − σ) by unit. Unit BLB1 is a geological section of the full cliff exposure from ground surface to below water level. The three colour bands indicate clusters of pIR IRSL ages grouped by mean ages and standard error of the mean. The earliest wood objects (BLB5, BLB3) are in the lower green band with a mean age of 476 ± 23 000 years. The blue band has a mean age of 390 ± 25 000 years and incorporates the wood object in BLB2. The overlying yellow band has a mean age of 324 ± 15 000 years and incorporates wood objects in BLB4. Red diamonds indicate modified wood objects. Barham et al. (2023).

At Kalambo Falls a nine-metre-deep exposure of fluvial deposits, interpreted as having been laid down by a laterally migrating river with moderate-to-high energy flows, comprises mostly gravels and course sands, with occasional non-contiguous beds of fine sand, silt, and clay. This deposit has an elevated water table, which has preserved wooden objects and plant matter within the bottom two metres of the sequence. Wooden items are interpreted as either having been deliberately deposited by Hominins or carried to its current location by the flow of the river. 

Modified wood tools from site BLB, Kalambo Falls, 2019. (a) BLB5 structural element (object 1033). (b) BLB3 ‘wedge’ (object 660). (c) BLB2 ‘digging stick’ (object 219). (d) BLB4 cut log. (e) BLB4, tapered piece with single chop-mark. Scale bars are 10 cm. Barham et al. (2023).

Sixteen dates were obtained from this sequence using a combination of optically stimulated luminescence dating of single quartz grains and postinfrared infrared stimulated luminescence dating of potassium-rich feldspars. These dates form a stratigraphic sequence (i.e. the older dates are below the newer dates in the succession), with one exception, and fall into three distinct age clusters. The oldest cluster, centred on 476 000 years ago (and extending approximately 23 000 years in either direction of this date) includes all of the samples from below the current river level, including two modified wooden objects, BLB3, which was found with a piece of unmodified wood and a collection of Acheulian tools, and BLB5, which was found with another group of Acheulian tools. The next cluster, centred on 390 000 years ago and extending 25 000 years on either side of that date, contained a single wooden tool, BLB2, found on its own, above the level of the current river, while the final cluster, centred on 324 000 years ago and extending 15 000 years on either side of that date, includes a pair of wooden artefacts, BLB4, found together.

It was possible to identify the wood from which the artefacts were made, but attempts at carbon dating them produced 'infinite' results, indicating they are more than about 50 000 years old. Infrared spectroscopy of these specimens showed that they had begun to mineralize, with silica beginning to replace the original wood. The tools were interpreted by comparison to later wooden tools from Holocene archaelogical sites in Zambia and the UK, as well as those made by modern Human populations.

The oldest tool, object 1033 from layer BLB5, is a Large-fruited Bushwillow, Combretum zeyheri, log 141.3 cm in length and 25.6 cm in width, which was found overlying another log at an angle of 75°. Importantly, this overlying log has a notch, 13.2 cm long and 11.4 cm wide, intentionally cut into it where it rests on the underlying log, which also shows signs of modification. Bark is still present on both logs, bur is absent around the notch, emphasizing that this was intentionally cut, although this is not in doubt, due to the visible chop and scrape marks on the exposed wood within the notch. 

Structural unit formed by two overlapping logs in BLB5. The underlying log passes through a central notch cut into the upper log (object 1033) and extends into the section. Plan view of the unit (left) and during excavation (right). The numbers refer to the distance in centimetres. Barham et al. (2023).

The notch shows several areas of scrape marks, overlapping in the centre. These are 'v'-shaped in profile, up to 24 mm long and 3.2 mm wide. The end of the log is tapered, and also appears to have been modified.

Annotated images of the BLB5 upper log (object 1033) showing areas of intentional modification. From left to right, the location of the central notch in profile, shaping marks in and on the margins of the notch (a)–(k), the notch in profile from the opposite side. The image on the right shows the upper surface of the log, and the three parts of the log (1)–(3) separated by cracks. White arrows indicate locations of shaping facets on the sides and upper surface of the log. Barham et al. (2023).

The underlying log also shows signs of modification, with a series of small striations running across the grain of the wood at its mid-point, again with 'v'-shaped profiles indicative of scraping, and the end of the log which passes through the notch in the upper log showing signs of having been intentionally thinned by the scrapping of a series of notches along the grain of the wood.

Shaping marks on the upper surfaces of object 1033 and on the underlying treetrunk. Clockwise, from left upper left; chop marks on Part 2; cluster of small convex hewing marks on Part 1, near Part 2; cutmark (upper arrow) and small facets (lower arrows) on Part 1 near Part 3; intercutting chop marks on the upper right edge of the Part 3 taper; underlying log midsection, intersecting cutmarks transverse to the grain (bold arrow, upper left, indicating direction of grain). Marks on underlying treetrunk interpreted as result of scraping, perhaps from debarking. Barham et al. (2023).

Infrared spectroscopy suggests that the notch has also been modified by fire-shaping, something which was reported on another log of similar size (165 cm) previously found with Acheulian artefacts at Kalambo Falls, but not dated, which also had a wide, deep groove cut into it and tapering ends. This wood was presumed to have been part of a structure, and thought to have been modified by the actions of Early Humans. The new discovery of two logs interlocking on a similar notch, strongly supports the idea that the function was constructional in purpose, although the age of the strata from which the wood was recovered considerably pre-dates the oldest estimates for the emergence of Modern Humans.

Shaping marks on the treetrunk underlying object 1033 notch, BLB5. Surface modifications on the treetrunk beneath and just beyond the notch. Images described counter clockwise: white arrows highlight direction of striations, some V-shaped in profile, cutting across the grain from the edge toward the middle of the surface; a set of parallel transverse striations/cutmarks, with V-shaped profiles (white arrows) along ridge descending to a flat tapered surface; inset detail of the striations on the ridge crest; overview of the set of striations along the ridge; profile view of the flattened surface below the ridge; profile view of the ridge and break of slope onto the flat tapering surface which extends beyond the notch; plan view of the flat tapering end with transverse striations and cutmarks with V-shaped profiles (white arrows) interpreted as shaping marks. Barham et al. (2023).

The second collection of material below the modern river level, BLB3, comprises another collection of Acheulian tools, including flake tools, cleavers, handaxes and core axes, as well as two wooden objects, a 'v'-shaped piece of Figwwod, Ficcus sp., showing no signs of intentional modification, and a flattened branch of Sausage Tree, Kigelia africana, 36.2 cm in length and with one end carved to a point.

Shaping and possible use marks on object 660, BLB3. Surface modifications on ‘wedge’ shown clockwise: white arrows indicating location of modifications on base and either side of the tip; basal crack (top arrow) and side split, facet ‘a’ intercepts a striation, possible use damage, and ‘b’ indicates a set of faint transverse striations; ‘c’ and ‘d’ intersecting facets above tip, ‘e’ and ‘f’ are sets of parallel faint transvers striations; tip face with convex step terminations, possibly from use. Barham et al. (2023).

Barham et al. believe that this artefact has been intentionally shaped by repeated high-impact blows, in order to form a wedge. Similar wedges have been recovered from the Mesolithic Starr Car site in the UK, and are known to have been used for a variety of purposes by Aboriginal Australians, but nothing similar has ever been discovered in a Middle Pleistocene deposit.

The BLB2 horizon, dated to about 390 000 years ago produced a single wooden item, broken into two pieces which fitted together; one of these was found still embedded in the sediment, the other in the river directly below, where it had apparently fallen. The combined wooded object is about 62.4 cm in length, made of African Sausagewood, stripped of all bark and intentionally fashioned into a point, being 11.9 cm wide at the base, 6.1 cm wide in the middle, and 1.3 cm wide at the tip. The object has striations cutting across the grain of the wood in several places, these being less than 10 mm wide and convex in profile. The tip of the object is slightly rounded, which might be a sign of wear from use. or derive from its time in the river. The object is interpreted as a digging stick similar to those used historically by foragers in the Kalahari. Similar artefacts are known from the Middle Holocene of Zambia, but again the Middle Pleistocene occurrence is unprecedented. 

Shaping marks on object 219, BLB2. Upper image shows all views of the object with white arrows indicating location of marks on either side of the tip and above the tip. Both sides of the tip (two images on left) have a faint set of transverse striations and two or more small facets away from the tip. (Scale bar is 1 cm.) The vertical image to the right shows four groups of faint parallel transverse striations in an area with two knots, no scale. The object is interpreted as a digging-stick. Barham et al. (2023).

The BLB4 horizon, dated to about 324 000 years ago, produced two wooden artefacts and no stone items. The uppermost of these is a rectangular piece of Large-fruited Bushwillow wood measuring 59.24 cm by 29.34 cm by 7.7 cm, with traces of bark and sapwood still present. This shows signs of having been flattened, but this may have been due to the weight of the sediment above it. It also has a large chop mark running across its obverse surface. Barham et al. interpret this item as a piece of tree trunk which has been intentionally cut to size, indicating a capacity to process large pieces of wood.

Chop marks on ‘cut log’, BLB4. Upper image shows all views of the object and location of modifications (white arrows) on the ends, ‘a’ and ‘b’, two marks on the underlying surface and the preservation of bark on both surfaces. Image below is ‘a’ with its distinctive stepped chop marks (black arrows), and underlying grey image (denatured RTI) shows the width of the step between the first and second chop-mark expanding, left to right, from 13 to 25 mm. The deep, slightly convex cut of the first chop is visible. The underly step expands left to right from 6 mm to 11 mm. A third step starts with a width of 7 mm. Bottom image is end ‘b’ with black arrows indicating location of chop marks. Barham et al. (2023).

The second item is a Sausagewood branch, with a side branch 37.9 cm in length, tapering from a 12.3 cm wide base to a 2.1 cm wide tip. The wood has been split centrally, and has a transverse chop mark above the tip. The purpose of this artefact is unclear.

Images of split branch, BLB4 (‘notched stick’). Above, close-up of the facet/chop-mark with arrow indicating direction of initiation. Below, all views of split branch with chop (white arrow) and close-up of the entry facet. The object was found cracked in situ. Barham et al. (2023).

The Kalambo Falls site has yielded a number of exceptionally well-preserved, intentionally modified wooded objects, with the most recent discoveries confidently dated to the Middle Pleistocene (and previous, undated discoveries likely to be of similar vintage). This has significant implications for our understanding of the technological capabilities of earlier members of the genus Homo, which have previously only been known from stone tools. The implications are clearly that these people were capable of felling large trees, and constructing objects such as platforms, which would have required considerable skills in selecting trees, felling them, and processing the wood obtained. Since this appears to have been done with stone tools, it shows that stone- and woodworking evolved together, and helps to explain some of the larger stone tools produced as part of the Acheulean technology. 

Between about 470 000 and about 274 000 years ago the Kalambo Falls site would have had an extensive forest cover and a high water table, leading to periodic flooding of the river plain. In such an environment the ability to produce raised platforms, wooden walkways, or even structures with solid foundations would have been highly advantageous.

The invention of hafted tools (tools with wooden handles) is thought to have occurred between about 500 000 and about 200 000 years ago, and would have required a good understanding of the properties of wood, and how to shape it by chopping and scraping. The interlocking logs at the lowest dated level at Kalambo Falls show a similar level of technological cognition, as well as a previously unanticipated ability to create the first built environments.

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Saturday 23 September 2023

Outbreak of Botulism in Bordeaux and the greater Ile-de-France Region.

On 12 September 2023, local public health authorities in France identified a cluster of 10 cases with suspected Botulism, including one death. As of 14 September 2023, the National International Health Regulations Focal Point for France has notified the World Health Organization of a total of 15 cases of suspected botulism, including one death, reported in Bordeaux and the greater Ile-de-France Region, according to a press release issued by the World Health Organization on 20 September 2023.

The epidemiological investigations indicated that the source of infection is the consumption of homemade preserved Sardines, on different dates, at the same restaurant in Bordeaux during the week of 4–10 September 2023. The food item was made at the restaurant for consumption on premises.

Due to the incubation period of up to eight days and the restaurant attracting international visitors during the Rugby World Cup, there is a possibility that additional cases among international visitors may be reported in France, or possibly outside France as travellers returned home, until 18 September.

On 12 September 2023, local public health authorities in France identified a cluster of 10 cases with suspected botulism, including one death, later identified as a 32-year-old woman married to an Irish national. 

As of 14 September 2023, the National International Health Regulations Focal Point for France has notified a total of 15 cases of suspected botulism, including one death, reported in Bordeaux and Ile-de-France. Of these 15 cases, 10 have been hospitalised, with eight patients being admitted to an Intensive Care Unit. Fourteen out of the 15 cases are reported among foreign citizens identified from six countries in addition to France. These include Canada, Germany, Greece, Ireland, the United Kingdom of Great Britain and Northern Ireland, and the United States of America. All suspected cases consumed the same product (Sardines in jars) on different dates at the same restaurant in Bordeaux during the week of 4–10 September 2023. The epidemiological investigations indicated that the source of infection is the consumption of homemade preserved Sardines. The food item was produced and served at the restaurant.

Botulism is a serious neurological condition caused by a very potent toxin produced by the Bacterium  Clostridium botulinum. It develops particularly in poorly preserved foods. Human Botulism may refer to foodborne Botulism, infant Botulism, wound Botulism, and inhalation Botulism or other types of intoxication.

The Bacterium Clostridium botulinum produces a toxin that can paralyze muscles and halt breathing. Eye of Science/Science Source.

Foodborne Botulism is a serious, potentially fatal disease. It is an intoxication caused by ingestion of potent neurotoxins (the Botulinum toxins) formed in contaminated foods. Person-to-person transmission of Botulism does not occur. The manifestations, or symptoms, of intoxication can vary, and is characterized by descending, flaccid paralysis that can cause respiratory failure. Early symptoms include marked fatigue, weakness and vertigo, usually followed by blurred vision, dry mouth and difficulty in swallowing and speaking. Vomiting, diarrhoea, constipation and abdominal swelling may also occur. The disease can progress to weakness in the neck and arms, after which the respiratory muscles and muscles of the lower body are affected. There is no fever and no loss of consciousness. Symptoms usually appear from several hours up to 8 days following consumption of contaminated food.

Although Botulism outbreaks are relatively rare, they are considered public health emergencies that require rapid recognition to identify the disease source, distinguish outbreak types (between natural, accidental or deliberate), prevent additional cases and effectively administer treatment to affected patients. Successful treatment depends significantly on early diagnosis and the rapid administration of the botulinum antitoxin and intensive respiratory care.

Incidence of Botulism is low, but the mortality rate is high if prompt diagnosis and appropriate, immediate treatment is not given. The disease can be fatal in 5% to 10% of cases.

On 11 September, food and serum samples were shipped to the French National Reference Center for Anaerobic Bacteria and Botulism at the Institute Pasteur in Paris , and Botulinum toxin was confirmed in serum samples and in a food sample (Sardines) on 14 September 2023.  Local health authorities inspected the restaurant and all products prepared by the restaurant have been recalled. On 13 September, the local health authorities held a press conference and informed the local healthcare professionals. National health authorities in France have issued risk communication advice to sensitize the health care workers about the symptomatology and treatment.  Information on cases reported among citizens from foreign countries have been shared with the relevant health authorities in those countries.

Local investigations have identified an estimated 25 persons through credit card receipts who have been exposed (i.e., who likely consumed the suspect food item). The exposure occurred at local level and measures have been implemented to eliminate the source of infection including the removal of the suspected food item, which was not distributed outside the venue. However, given the ranging incubation period of Botulism (up to eight days) and that not all customers of the restaurant in Bordeaux may have been identified despite efforts, further cases linked to this event may still occur. This outbreak has occurred at the same time as the Rugby World Cup held from the week of 4 September 2023 attracting followers and rugby teams from all over the world.

The restaurant in Bordeaux where a woman died, and several other people became severely ill after consuming Sardines. Ugo Amez/SIPA/Shutterstock.

Prevention of foodborne Botulism is based on good practice in food preparation particularly during heating/sterilization and hygiene. Foodborne botulism may be prevented by the inactivation of the Bacterium and its spores in heat-sterilized (for example, retorted) or canned products, or by inhibiting Bacterial growth and toxin production in other products. The vegetative forms of Bacteria can be destroyed by boiling, but the spores can remain viable after boiling even for several hours. However, the spores can be killed by very high temperature treatments such as (commercial) canning.

The neurotoxins themselves are heat-labile and will be destroyed within minutes at temperatures above 80°C; consequently, only foods improperly processed in which the bacteria or the spores survive, pose a risk.

The World Health Organization produces a Five Keys to Safer Food Manual which serve as the basis for educational programmes to train food handlers and educate the consumers. They are especially important in preventing food poisoning. 

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Asteroid 2023 SC2 passes the Earth.

Asteroid 2023 SC2 passed by the Earth at a distance of about 173 500 km (45% of the average distance between the Earth and the Moon or 0.12% of the distance between the Earth and the Sun), with a velocity of about 18.46 km per second, slightly after 2. 50 pm GMT on Monday 18 September 2023. There was no danger of the asteroid hitting us, though were it to do so it would not have presented a major threat. 2023 SC2 has an estimated equivalent diameter of 3-8 m (i.e. it is estimated that a spherical object with the same volume would be 3-8 m in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) more than 35 km above the ground, with only fragmentary material reaching the Earth's surface.

The relative positions of 2023 SC2 and the Earth at 3.00 pm on Moday 18 September 2023. JPL Small Body Database.

2023 SC2 was discovered on 19 September 2023 (the day after its closest approach to the Earth) by the University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount Lemmon in the Catalina Mountains north of Tucson. The designation 2023 SC2 implies that the asteroid was the 53rd object (asteroid C2 - in numbering asteroids the letters A-Z, excluding I, are assigned numbers from 1 to 25, with a number added to the end each time the alphabet is ended, so that A = 1, A1 = 26, A2 = 51, etc., which means that C2 = (25 x 2) + 3 = 53) discovered in the second half of September 2023 (period 2023 S - the year being split into 24 half-months represented by the letters A-Y, with I being excluded).

2023 SC2 is calculated to have a 1072 day (2.94 year) orbital period, with an elliptical orbit tilted at an angle of 4.39° to the plain of the Solar System which takes in to 0.70 AU from the Sun (70% of the distance at which the Earth orbits the Sun, and slightly inside the orbit of Venus) and out to 3.40 AU (3.40 times the distance at which the Earth orbits the Sun, somewhat more than twice the distance at which the planet Mars orbits). It is therefore classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer). 

The relative positions and orbits of 2023 SC2 and the Earth at 3.00 pm on Monday 18 September 2023. JPL Small Body Database.

Asteroid 2023 SC3 is calculated to have had one previous close encounter with the Earth, in October 2020; no further such encounters are predicted at this time.

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Thursday 21 September 2023

The September Equinox

The September Equinox falls on Saturday 23 September this year (2023), when the day and night will be of equal length in both of the Earth's hemispheres. The Earth spins on its axis at an angle to the plain of the Solar System. This means that the poles of the Earth do not remain at 90° to the Sun, but rather the northern pole is tilted towards the Sun for six months of the year (the northern summer), and the southern pole for the other six months (the southern summer). This means that twice a year neither pole is inclined towards the Sun, on days known as the equinoxes.

Simplified diagram showing the tilt of the Earth throughout the year. Not to scale. The Human Adventures in Space Exploration.

The equinoxes fall each year in March and September, with the March Equinox being the Spring (or Vernal) Equinox in the Northern Hemisphere and the Autumn Equinox in the Southern Hemisphere, while the September Equinox is the Autumn Equinox in the Northern Hemisphere and the Spring Equinox in the Southern Hemisphere. On these two days the day and night are both exactly twelve hours long at every point on the planet, the only days on which this happens.

How the combination of the Earth's equatorial plane (horizontal circle labelled as Celestial equator) and the plane of the Earth's orbit (diagonal circle labelled as Path of the Sun) creates the Solstices and Equinoxes that we observe. Christopher Crockett.

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Wednesday 20 September 2023

Mangnitude 6.0 Earthquake beneath South Island, New Zealand.

The GeoNet project, which monitors quakes in New Zealand, recorded a Magnitude 6.0 Earthquake at a depth of 11 km, about 43 km to the west of the town of Geraldine in the Canterbury Region of South Island, New Zealand, slightly before 9.15 am local time on Wednesday 20 September 2023 (slightly before 9.15 pm on Tuesday 19 September GMT). No damage or casualties have been reported following this event, but people have reported feeling it across much of New Zealand.

Ths approximate location of the 20 September 2023 South Island Earthquake. GeoNet.

New Zealand is located on the boundary beneath the Australian and Pacific Plates. Beneath the islands the Pacific Plate is being subducted beneath the Australian Plate. This causes a great deal of friction which causes Earthquakes where the boundary between the two plates is close to the surface; this is to the east of North Island, but onshore on South Island, where it can lead to strong Earthquakes. Technically such quakes also occur where the plate margin is deeper, but these are felt less strongly as the rocks between the boundary and the surface absorb much of the energy, making strong tremors much less frequent on North Island. As the Pacific Plate sinks deeper into the Earth it is partially melted by the friction and the heat of the planet's interior. Some of the melted material then rises through the overlying Australian Plate, fuelling the volcanoes of New Zealand.

The subduction zone beneath New Zealand, and how if fuels Earthquakes and volcanos. Te Ara.

Witness reports of Earthquakes can help scientists to understand these events, and the underlying geologic processes that cause them. If you this quake then you can report it to the GeoNet here.

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Body of 1300-year-old Frankish warrior unearthed at Ingelheim am Rhein.

Archaeologists working at an early medieval cemetery at Ingelheim am Rhein, about 40 km to the west of Frankfurt, this June unearthed the body of a Frankish warrior dating from about 1300 years before the present, according to a press release issued by the Kaiserpfalz Ingelheim on 4 August 2023. The body was located in a Merovingian cemetery between Rotweinstrasse and Stevenagestrasse, which had been under investigation since 2015. Most of the graves within the site had previously been looted during the later medieval period, so the discovery came as somewhat of a surprise. 

The warrior was armed with a spathe, a double-edged sword with a blade of about 75 cm and a total length of about 90 cm, originally made popular by Roman cavalry officers, but widely used in the early medieval period, as well as a sax, a second shorter sword with a heavy cutting edge, and a large knife, as well as a spear and a shield. 

The warrior from grave 447 with his impressive arsenal of weapons: shield boss, sword (spatha) and broadaxe as well as, next to the head, the tip of the lance. Another heavy knife is hidden under the skeleton. Christoph Bassler/Kaiserpfalz Ingelheim.

The warrior is thought to have been between 30 and 40 years of age at the time of his death, although how he died is unclear, with no signs of either physical injury or disease found on his skeleton to date. Despite his impressive array of arms, he is unlikely to have been either a professional soldier or particularly rich. Instead, he was probably a comfortably off freeman, who would have been expected to maintain a set of arms and serve in his lords militia when called upon to do so. 

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