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Archaeologists at the archaeology research institute of the Chinese Academy of Social Sciences have unveiled the details of a deluxe carriage unearthed in a cemetery dating back to the Eastern Zhou Dynasty (770-256 BC) in north China's Hebei Province.

Credit: Xinhua

According to the archaeologists, the carriage is 142.5 cm wide, 106 cm in length and has two wheels with a diameter of 140 centimeters and 38 spokes each. The large volume of the carriage is rare for those that date back to the times before the Qin Dynasty (221-206 BC), said Li Cunxin, an associate researcher.

The archaeologists also found many exquisite patterns painted on the surface of the carriage and a pair of beast-shaped metal badges embedded into the carriage that have gold foil decorations stuck to them, which still hold their shine even after being underground for such a long period of time.

Credit: Xinhua

Researchers speculated that the occupant of the cemetery was high up in the social pecking order and could be at the level of a tribal leader.


The archaeological team is currently trying to further unveil the details of the carriage via various technologies before fully restoring the finding in the future.

Source: Xinhua [December 10, 2018]

A team of scientists led by Jingmai O'Connor from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences, reported the first occurrence of medullary bone in Enantiornithes, the dominant clade of birds during the Cretaceous.

Main slab of Pengornithid Enantiornithine, preserved in three-dimensions unlike most compression fossils  from the Jehol Biota. Scale bar is one centimetre [Credit: Jingmai O'Connor]

Medullary bone is a bone tissue unique to birds today. It is present only in females about to lay eggs and forms in the empty spaces within the skeleton. This bone tissue serves as a reservoir for calcium needed to form the eggshell. Medullary bone has been reported in a variety of non-avian dinosaurs including Tyrannosaurus rex, ornithopod dinosaurs like Tenontosaurus, and several sauropods (huge long-necked dinosaurs) including Mussasaurus. It has also been identified in pterosaurs, which are flying reptiles closely related to dinosaurs.

Since the first report of medullary bone in a Mesozoic fossil in 2005, this tissue has attracted great interest because it links birds and dinosaurs. However, the presence of this bone tissue in pterosaurs and non-avian dinosaurs is perplexing. Non-avian dinosaurs were so large and their eggs so small that they shouldn't have required medullary bone. Since pterosaurs laid soft-shelled eggs, they also shouldn't have required medullary bone.

Cross section of the femur bone viewed under polarized light showing the thick layer of medullary bone within the medullary cavity [Credit: Jingmai O'Connor]

Some reported instances of medullary bone are probably actually bone pathologies causing abnormal growth. However, in this report, IVPP scientists, working together with Mark Norell from the American Museum of Natural History and Greg Erickson from Florida State University, argued that no previous description of medullary bone in a Mesozoic reptile was well supported.

The new report is the best support for medullary bone in the Mesozoic so far since it was found throughout the entire preserved skeleton, suggesting it was part of a system-wide process rather than a local pathology. However, the authors concede that scientists still know too little about medullary bone to confirm, without additional evidence (e.g., association with a nest or eggs), that the fossilized individual with this tissue was reproductively active.

In light of the currently available evidence, medullary bone might have been an entirely avian feature even in the Mesozoic. It evolved as a result of the thinned, hollow bones in birds, which lightened the skeleton for flight, as well as their increased egg size.

The findings were published in Nature Communications.

Source: Chinese Academy of Sciences [December 05, 2018]

Scientists long believed that the lower mantle was composed of Bridgmanite (Mg,Fe)SiO₃ and magnesiowüstite (Mg,Fe)O, in which Fe2+ dwells. This view changed when experiments showed that Fe²⁺ simply can't exist at the pressure and temperature of the lower mantle. What is present is Fe³⁺. The two phases (Mg,Fe)SiO₃ and (Mg,Fe)O both shed Fe²⁺ and, in turn, MgSiO₃ and MgO remain. However, what mineral hosts Fe³⁺ had remained a secret.

Maohokite [Credit: CHEN Ming]

Now scientists have a possible answer: Maohokite, a newly discovered high-pressure mineral. It may be what composes the Earth's lower mantle along with Bridgmanite MgSiO₃ and magnesiowüstite MgO. The study reporting this new mineral was published in Meteoritics & Planetary Science.

Maohokite was discovered by CHEN Ming's team from the Guangzhou Institute of Geochemistry of the Chinese Academy of Sciences and SHU Jinfu from the Center for High Pressure Science and Technology Advanced Research. The mineral was named after Hokwang Mao, in honor of his great contribution to high-pressure research.

The mineral and its name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association under the designator IMA 2017-047.

Natural minerals can be divided into two types: low-pressure minerals and high-pressure minerals, depending on their formation pressures. The pressure and temperature required for the formation of high-pressure minerals can only be provided by the environment of the mantle or the hypervelocity collision between celestial bodies.

Maohokite is the second case. It was found in shock-metamorphosed rocks from the Xiuyan impact crater in China.

This high-pressure mineral was formed from the decomposition of ferromagnesian carbonate via a self-oxidation-reduction reaction at a temperature >900 °C and impact pressure >25 GPa (a pressure range found at depths more than 670km below Earth's surface). In this reaction,  Fe²⁺ oxidizes into Fe³⁺ and then later combines with  Mg²⁺ to form maohokite, thus making it a possible important constituent of the lower mantle.

Maohokite, with a composition of MgFe₂O₄, has an orthorhombic CaFe₂O₄-type structure. The existing mineralogical model of the Earth's mantle shows that the ferromagnesian lower mantle is mainly composed of Bridgmanite (Mg,Fe)SiO₃ and magnesiowüstite (Mg,Fe)O. Therefore, the fact that Maohokite contains Mg and Fe, two major components of the lower mantle, only makes the case stronger that Maokohite is a key mineral in the lower mantle.

Source: Chinese Academy of Sciences [December 05, 2018]

Archaeologists said the Lushanmao historic relics site in the Baota district of Yan'an city, Northwest China's Shaanxi province, could be the country's prototype for early palaces.

Aerial view of the Lushanmao site in the Baota district of Yan'an city, Northwest China's Shaanxi province [Credit: China Daily]

Experts from the Shaanxi Provincial Institute of Archaeology recently found a foundation of rammed earth, on which there could have been a neatly arranged courts, walls and architectural complex.

Jadeware was found in the foundations of some buildings.

Archaeologists work at the the Lushanmao site in the Baota district of Yan'an city, Northwest China's Shaanxi province [Credit: China Daily]

Pottery unearthed at the Lushanmao site [Credit: China Daily]

Jade ware unearthed at the Lushanmao site [Credit: China Daily]

Stone spearhead? unearthed at the Lushanmao site [Credit: China Daily]

The site, covering an area of two million square meters, is one of the largest prehistoric settlement sites in China.

A large number of artefacts including pottery, stoneware, boneware and jadeware have been unearthed at the site previously.

Aerial view of the Lushanmao site in the Baota district of Yan'an city, Northwest China's Shaanxi province [Credit: China Daily]

Based on features of the unearthed artifacts, the site's history can be traced back around 4,500 years, according to experts.

Source: China Daily [November 29, 2018]

The funerary complex of the first Chinese emperor of the Qin dynasty (3th century BC) is one of the most famous archaeological sites in the world. This is of course due to the discovery of the statues of the terracotta army, intended to accompany the emperor in the afterlife. Much less known than the statues is the fact that tomb proper (still not excavated) lies beneath a gigantic, artificial hill of rammed earth. This hill has a square shape, a base side of more than 350 meters and is over 40 meters high, so that it can easily be called a pyramid.

This is the huge mole of the Maoling Mausoleum of Emperor Wu of Han [Credit: Giulio Magli]

Even less known is the fact that also all the emperors of the subsequent dynasty, the Western Han, chose to be buried under similar pyramids. These mausoleums are visible still today within the rapidly developing landscape of the northwestern surroundings of Xian along the Wei River. Including also the tombs of the queens and other members of royal families, there are over 40 of such "Chinese pyramids". Of these, only two have been (partly) excavated.

The new study is part of an extensive program of research on the role of astronomy and of the traditional doctrine of "feng shui" in the Chinese imperial necropolises and has just been published in the academic journal Archaeological Research in Asia.

In the work simple techniques based on satellite images are used, together with field surveys, to collect a large number of new data and, in particular, to study the orientation of the pyramid bases. It is in fact well known that, for example, the Egyptian pyramids are oriented with great precision to the cardinal points, by virtue of the very strong bonds of the funerary religion of the Egyptian pharaohs with the sky and in particular with the circumpolar stars.

The Terracotta Warriors protecting the Qin Mausoleum's east front [Credit: Giulio Magli]

Although - of course - there is no connection with the Egyptian pyramids, also the Chinese emperors credited their power as a direct mandate of the heaven, identifying the circumpolar region as a celestial image of the imperial palace and its inhabitants. It was therefore natural to expect the Chinese pyramids, tombs of the emperors, to be oriented to the cardinal points. In this connection, the results of the new study are in part surprising.

It turns out that these monuments can be classified according to two "families". One such families comprises monuments oriented with good precision to the cardinal points, as expected. In the other family there are significant deviations from the true north, all of comparable and all on the same "hand "(to the west of the north looking towards the monument).

It is out of the question that this second family may have been due to errors of the Chinese astronomers and architects. One could think of the use of the compass, which was invented in China in a somewhat rudimentary form at that time, but there is no correspondence with the paleomagnetic data. The explanation proposed in the article is thus astronomical: the emperors who built the pyramids of the "family 2" did not want to point to the north celestial pole, which at the time did not correspond to any star, but to the star to which the pole would be approached in the future: Polaris.

All this discourse may look strange at first sight, but it must be remembered that there is a phenomenon, the precession of the earth's axis, which slowly but constantly moves the position in the sky in which the earth's axis points, and therefore the celestial pole. The Chinese astronomers were almost certainly aware of this. Nowadays we are used to identify the north celestial pole with Polaris (although in reality the correspondence is not perfect) but at the time of the Han emperors the pole was still far from Polaris, and with a distance in degrees approximately equal to the deviation of the Chines pyramids from the geographic north.

Source: Politecnico di milano [November 28, 2018]