Lake of mercury china

Lake of mercury china DEFAULT

Liquid mercury found under Mexican pyramid could lead to king's tomb

An archaeologist has discovered liquid mercury at the end of a tunnel beneath a Mexican pyramid, a finding that could suggest the existence of a king’s tomb or a ritual chamber far below one of the most ancient cities of the Americas.

Mexican researcher Sergio Gómez announced on Friday that he had discovered “large quantities” of liquid mercury in a chamber below the Pyramid of the Feathered Serpent, the third largest pyramid of Teotihuacan, the ruined city in central Mexico.

Gómez has spent six years slowly excavating the tunnel, which was unsealed in after 1, years. Last November, Gómez and a team announced they had found three chambers at the tunnel’s ft end, almost 60ft below the temple. Near the entrance of the chambers, they found a trove of strange artifacts: jade statues, jaguar remains, a box filled with carved shells and rubber balls.

Slowly working their way down the broad, dark and deep corridor beneath the pyramid, battling humidity and now obliged to wear protective gear against the dangers of mercury poisoning, Gómez and his team are meticulously exploring the three chambers.

Mercury is toxic and capable of devastating the human body through prolonged exposure; the liquid metal had no apparent practical purpose for ancient Mesoamericans. But it has been discovered at other sites. Rosemary Joyce, a professor of anthropology at the University of California, Berkeley, said that archaeologists have found mercury at three other sites around Central America.

Gómez speculated that the mercury could be a sign that his team is close to uncovering the first royal tomb ever found in Teotihuacan after decades of excavation – and centuries of mystery surrounding the leadership of the cryptic but well-preserved city.

The mercury may have symbolized an underworld river or lake, Gómez postulated, an idea that resonated with Annabeth Headreck, a professor at the University of Denver and the author of works on Teotihuacan and Mesoamerican art.

The shimmering, reflective qualities of liquid mercury may have resembled “an underworld river, not that different from the river Styx,” Headrick said, “if only in the concept that it’s the entrance to the supernatural world and the entrance to the underworld.”

“Mirrors were considered a way to look into the supernatural world, they were a way to divine what might happen in the future,” she said. “It could be a sort of river, albeit a pretty spectacular one.”

Joyce said that archaeologists know that scintillation fascinated the ancient people generally, and that the liquid mercury may have been regarded as “somewhat magical … there for ritual purposes or symbolic purposes.”

Headrick said that mercury was not the only object of fascination: “a lot of ritual objects were made reflective with mica,” a sparkling mineral likely imported to the region.

In archaeologists using a robot found metallic spheres which they dubbed “disco balls” in an un-excavated portion of the tunnel, near pyrite mirrors. “I wish I could understand all the things these guys are finding down there,” Headrick said, “but it’s unique and that’s why it’s hard.”

Water was also precious to many of the people of Mesoamerica, who knew of underground water systems and lakes that could be accessed through caves. Teotihuacan once had springs as well, though they are now dried out.

Joyce said the ancient Mesoamericans could produce liquid mercury by heating mercury ore, known as cinnabar, which they also used for its blood-red pigment. The Maya used cinnabar to decorate jade objects and color the bodies of their royalty, for instance; the people of Teotihuacan – for whom archaeologists have not agreed on a name – have not left any obvious royal remains for study.

The discovery of a tomb could help solve the enigma of how Teotihuacan was ruled, and Joyce said that the concentration of artifacts outside the tunnel chambers could be associated with a tomb – or a set of ritual chambers.

A royal tomb could lend credence to the theory that the city, which flourished between AD, was ruled by dynasties in the manner of the Maya, though with far less obvious flair for self-glorification.

But a royal tomb could also hold the remains of a lord, which may fit with a competing idea about the city. Linda Manzanilla, a Mexican archaeologist acclaimed by many of her peers, contends that the city was governed by four co-rulers and notes that the city lacks a palace or apparent depiction of kings on its many murals. The excavation by Gomez my find one of those co-rulers, under this hypothesis.

Headrick suggested yet more fluid models, in which strong lineages or clans traded rule but never cemented into dynasties, or in which the rulers relied on agreements with the military to maintain power, and authority was vested more in an office than a family. Ancient Teotihuacan was a city with familiar factions vying for influence: the elite, the military, the merchants, the priests and the people.

For now, the archaeologists and anthropologists continue digging and deducing. Gomez says he hopes excavation of the chambers to be complete by October, and Headrick said that archeologists are looking at the city from new angles. Some are trying to decipher the paintings and hieroglyphics around the city, others trying to parse what may be a writing system without verbs or syntax.

Then there are the thousands of artifacts, some unprecedented and bizarre, that Gomez and his fellows are disinterring from beneath the pyramid. “It’s quite the mystery,” Headrick said. “It’s fun.”


The martial figures buried with the first Chinese emperor were discovered in But the tomb they guard hasn’t even been opened, writes Jonathan Glancey.


In March , Yang Zhifa, a farmer, along with his five brothers and their neighbour Wang Puzhi, were digging a well in pomegranate and persimmon fields an hour’s bus ride northeast of Xi’an, capital of China’s Shaanxi province. Their shovels hit a terracotta head they mistook for an image of the Buddha. Within months, teams of archaeologists and officials arrived on the scene.

What the farmers had stumbled upon proved to be one of the greatest archaeological discoveries of the 20th Century. Buried below the fields were thousands of life-sized and deftly sculpted terracotta warriors dating from the 3rd Century BCE reign of Qin Shi Huang, the first emperor of a united China.

Qin Shi Huang, who died aged 49 in BC, was the first emperor to unite the warring states of China into a single nation (Credit: Wikipedia)

Perhaps it was lucky that this subterranean army had been discovered at the tail end of Mao Zedong’s Cultural Revolution. In , zealous Red Guards had made a manically destructive raid on the underground tomb of the Ming emperor Wanli () outside Beijng. The skeletons of the emperor and two of his empresses were dragged to the door of the tomb, publicly denounced and burned. This was some years before the People’s Republic began investing in tourism and new museums, some 4, of them since the red star set on the Cultural Revolution in

Qin Shi Huang was obsessed with attaining immortality and sent Xu Fu on an sea voyage to find the elixir of life – Xu never returned (Credit: Alamy)

The uncovering of legions of life-like terracotta warriors excited China and thrilled the world. Qin Shi Huang’s soldiers marched into the British Museum in September Over the next six months more than , visitors came to inspect them. Only ’s Treasures of Tutankhamun show drew a bigger crowd. Some of the warriors are now going on show among other works of art drawn from 32 Chinese museums and archaeological institutions in the exhibition Age of Empires: Chinese Art of the Qin and Han Dynasties at New York’s Metropolitan Museum of Art, and a veritable army of visitors is expected. 

The warriors are indeed special. Buried in formation in brick-lined trenches, each appears to have its own character, although in fact their moustachioed faces are derived from 10 basic types. Originally painted in bright red, blue, pink and gold, today Qin Shi Huang’s kit-of-parts warriors are bleached of colour. Time and the ravages of nature have also robbed the warriors of the real weapons they once bore.

Ye who enter

Intriguingly, the sheer number of warriors and their armoury suggest they were made through an early form of mass production. And, yet, should we have expected anything less from Qin Shi Huang, the dynamic young king who united China in BCE and forged his vast empire together through the imposition of single systems of writing, money, weights and measures along with die-straight canals and roads? To protect his northern border, the emperor began construction of the Great Wall of China.

Hugely ambitious, Qin Shi Huang sought eternal life. He dispatched a minister overseas, never to return, in search of a magic potion. Knowing of ancient kings and sages who had lived 10, years and more by ingesting cinnabar (mercury sulfide), the emperor took to drinking draughts of wine sweetened with honey and laced with mercury.

Qin was interred in a massive mausoleum, still unopened to this day, that was surrounded by the terracotta army (Credit: Alamy)

By the time he died at the age of 49, presumably through mercury poisoning, Qin Shi Huang had all but completed his colossal underground tomb. If he were unable to rule forever in waking life, then he would be emperor until the end of time in the afterlife.

More than m people visit the terracotta warriors excavation site in Xi’an annually – and they have drawn huge crowds at museums around the world (Credit: Alamy)

The scale of the Chinese emperor’s mausoleum, the size of a great ancient city, remains breathtaking, its core a pyramid that once rose to m (ft). Less than half this height today and long greened by vegetation the pyramid remains clearly visible. In terms of Chinese tradition, it forms the eye of a propitious landscape that can be read as a dragon.

Tomb raiders

As for the 8, terracotta warriors, these – standing in line beyond the tomb itself – are there to guard the secrets of Qin Shi Huang’s underground empire. And secrets there are, and will be for many years to come, as the tomb remains sealed.

Archaeologists and museologists worldwide agree that opening the tomb would be a disaster, as exposure to air would damage it irreparably. In early digs to uncover the terracotta warriors, the lacquer beneath their painted faces and uniforms curled after just 15 seconds. More than this, though, according to 2nd Century BCE historian Sima Qian – whose description of the mausoleum has proven to be far more accurate than modern historians had once thought – rivers of mercury surround the emperor’s burial chamber. If they do, this would be a treacherous place to enter. Recent scientific studies have shown that soil here contains unusually high concentrations of mercury, although whether or not the emperor’s advisors could have produced so much liquid metal remains a matter of conjecture.

Terracotta horses, carts and chariots were also carved and buried to guard the emperor’s tomb (Credit: Alamy)

If no one is willing to enter, or even to probe the tomb for fear of causing damage to the treasures that surely lie within, there are further reasons for keeping well away. According to Sima Qian, mechanical crossbows guard entrances and passageways. Do they exist? Have they rotted away, or – chromium-plated – might they still send deadly bolts hissing through the darkness towards the flesh-and-blood torsos of would-be Indiana Joneses?

The radicalized student Red Guards of the Cultural Revolution had previously exhumed, denounced and burned the emperor Wanli’s corpse (Credit: Alamy)

Until new techniques are discovered, the secrets of Qin Shi Huang’s tomb will remain a haunting mystery. In the meantime, the army of terracotta warriors found beyond it are enveloped in supposition, too. As further pits were revealed during the s, mounted warriors and chariots driven by life-like horses were uncovered along with simulacra of generals and high-ranking officials. The top-knotted infantrymen known to so many museum visitors – in their own special way, the terracotta warriors have conquered the world – have been joined since by standing and kneeling archers, spear-wielding charioteers, strongmen, acrobats, dancers, musicians and exquisite bronze sculptures of swans, ducks and cranes.

Samples of DNA taken from a number of skeletons suggest that some of the emperor’s enormous workforce were of European origin. Had Ancient Greeks shown the Chinese how to sculpt figures and horses as magnificently as Phidias and his studio had when they carved the frieze of the Parthenon in 5th Century BCE Athens? Certainly nothing like the terracotta warriors or their cavalry’s horses had been seen in China before the building of Qin Shi Huang’s mausoleum.

Yang Zhifa discovered three statues on his farmland in There were 7, more to be discovered by others (Credit: Alamy)

We can only wait to find out more about this astonishing place, its secrets first uncovered by Yang Zhifa, his brothers and Wang Puzhi 43 years ago. Unlike the terracotta warriors this gang of seven has struggled to survive – the farmers made little or nothing from their discovery. In the interest of tourism, their land was taken away. In , poverty stricken and sick, Wang Puzhi hung himself. Within three years, Yang Wenhai and Yang Yanxin, jobless and unable to afford doctors, died in their early 50s.

In , Liu Xiquin, wife of Yang Quanyi, whose family home had been demolished, told the South China Morning Post, that her husband was afraid that he and his brothers “might have brought misfortune in some way, and does still wonder if maybe the soldiers should have been left beneath the ground.”

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Mercury as a Geophysical Tracer Gas - Emissions from the Emperor Qin Tomb in Xi´an Studied by Laser Radar


Mercury is, because of its high vapor pressure and its prevalence in the atmosphere as atoms, an interesting geophysical tracer gas, also with potential archaeological applications. According to historical records dating back years, the mausoleum chamber of the “Terracotta Army Emperor” Qin in Xi´an, China, contains large amounts of liquid mercury, considered as an elixir of life at the time. We here report on measurements of the atmospheric contents of atomic mercury above the tomb mound performed with a mobile differential absorption lidar (light detection and ranging) system. Our measurements, which were performed from three different locations around the mound, indeed indicate elevated atmospheric mercury levels, with localizations, which correlate with previous in situ soil sampling results. Concentrations up to 27 ng/m3 were observed, significantly higher than the typical general pollutant level in the area which was found to be around 5–10 ng/m3. An out-flux of about 5×10−8 kg/s was estimated. Highly volatile mercury may be escaping through cracks, which developed in the structure over time, and our investigation supports ancient chronicle records on the tomb, which is believed never to have been opened/looted. Our findings also have bearings on the proposed use of mercury as a tracer gas for valuable ores and geothermal resource exploration, and also bring problematics around reliable nuclear waste long-term underground storage to mind.


The high vapor pressure of mercury also at ambient temperatures, makes it an interesting geophysical tracer gas. The fact that mercury is the only non-inert gas element, which is present in the atmosphere in atomic form makes optical spectroscopy methods particularly sensitive, and allows mercury detection down to the Atlantic background level of 1–2 ng/m3 (see, e.g. ref. 1 and references therein). Mercury is a highly toxic heavy metal, leading to an internationally suggested ban of its use, as implemented by many countries2. A large international conference dealing with all aspects of mercury pollution is arranged every second year3. Remote sensing of atomic mercury has been accomplished using the differential absorption lidar (light detection and ranging) method over ranges up to 1 km, related to industrial emissions (see, e.g.4,5) and to geothermal resources and mines1,6,7. There is a potential to discover valuable mineral resources by mercury vapor detection, since mercury is frequently coexisting with certain ores (see, e.g.8). Likewise, underground thermal resources might be revealed by surface mercury anomalies9. It could even be speculated on the use of localized atmospheric mercury anomalies as precursors to imminent seismic and/or volcanic activities. All these applications are challenging, but the demonstrated capability of extremely sensitive, range-resolved remote sensing of mercury gas is encouraging. In our quest to develop such geophysical exploration tools, we have pursued a much related project – the search for mercury escaping from the emperor Qin Shi Huang’s underground mausoleum in Xi’an – arguably the World’s most famous archeological site.

Emperor Qin, who unified China and ruled over the vast territory in – BC, has kept the fascination and interest of people, in particular after the discovery of the Terracotta Army protecting his mausoleum. The tomb is located in Lintong, 30 km north-east of present-day Xi’an and was constructed during 38 years from BC, when he, at an age of 13, became king of a smaller region, up till BC, two years after his death, which probably was caused by mercury poisoning. According to historian Sima Qian, who documented the life of the emperor10, the mausoleum and surrounding structures were built by workers. He also stated, that the tomb chamber contained considerable amounts of liquid mercury, presumably forming rivers and lakes on a large-scale map of China. Further, mercury was at that time considered as an elixir of life. Mercury could be processed out of cinnabar (HgS) ore since ancient times11,12. The base of the pyramid-like tomb mound is about  ×  m2 and it has a present height of about 50 meters. According to geo radar and gravimeter investigations, the underground palace has a size of about  ×  × 30 m3 while the central coffin chamber measures 80 × 50 × 15 m3, with its ceiling about 30 meters below the present surrounding ground level13,14. Current understanding is that the chamber has never been opened/looted, and a detailed archeological investigation is postponed awaiting improved methods to safeguard artifacts from air exposure and swift degradation.

Our hypothesis in the current study was that, if mercury, at the amounts as estimated at tons or more, would have been introduced into the tomb chamber, then the likely formation of cracks in combination with the high natural vapor pressure of mercury would result in a faint still ongoing emission of atomic mercury vapor from the mound, and should be detectable by mapping the surrounding air. Actually, mercury, unlike other elements, stays in atomic form in the atmosphere, and the differential absorption lidar (DIAL) technique15 is able to measure atmospheric mercury concentrations down to the Atlantic background level of about 1–2 ng/m3 if averaged over a 1-km range1. In ancient China, it seems that it became a custom to introduce mercury into the tombs of the nobility. In the Song Dynasty (–), after the death of high-ranked persons like a minister, mercury was given for graves as a reward from the emperor16,17. Mercury fumes were in fact used in the localizing of a tomb in the Chinese city of Hancheng18. Actually, our preparations for the present measurements were initiated already in , but could not for different reasons, including legislation, be performed until now.

Systematic measurements of the soil covering the Qin mausoleum mound have actually revealed elevated levels of mercury, up to ppb and with an average value of ppb in one study, which is reported in ref. 19,20, while a newer investigation found ppb and ppb, respectively21, considerably higher than typical background values for the area. Studies of mercury related to the Qin mausoleum are discussed in22, while corresponding mercury studies in the open atmosphere have to our knowledge not been performed earlier. Clearly, any measurements of atmospheric mercury of possibly archaeological origin have to carefully consider mercury levels due to environmental pollution, which is high in the Xi’an area, and wind direction monitoring is clearly important.

During the time period July 24 to August 12, , with very hot weather favoring emission (typical daytime temperatures reaching 35 degrees and night-time temperatures around 30 degrees) we performed extensive measurements of the atmospheric mercury content around the tomb. We used a mobile differential absorption lidar system23, recently constructed, largely for this particular purpose, by the South China Normal University Applied Laser Spectroscopy Group. Lidar is a remote-sensing technique able to measure atmospheric gases by transmitting a pulsed laser beam and observing the back-scattered light from different range intervals. The range-resolution achievable depends on the concentration of the gas, and is degrading with lower concentrations. The system is shown in Fig. 1 in one of the measurement positions used (#1), about meters from the top of the tomb mound. A photograph of the system taken from the top of the pyramid is also included. Figure 2 gives an overview of the measurement area also showing the location of the Terracotta army pits about 2 km to the east of the tomb pyramid. Our three different measurement sites surrounding the pyramid are indicated in the figure by 1, 2, and 3. Further, the locations with highest soil mercury content according to19,20 and21 are indicated on the mound by symbols A and B, respectively. A weather station was installed at the top of the tomb mound, and a further one at the lidar system, at each location about 7 meters above the surrounding ground level.

Measurement site situation. The SCNU mobile differential absorption lidar system on site #1 (as indicated in Fig. 2) in front of the Qin mausoleum, which is seen in the background. A view towards the lidar system as seen from the top of the pyramid is shown to the right.

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Schematic view of the measurement site with the Emperor Qin Mausoleum and the Terracotta Warrior site. The three measurement positions (#1, #2, and #3) of the lidar system are shown with distances indicated. Inserts show a photograph of part of the about man strong army, as well as an ancient drawing of Emperor Qin. A and B indicate the locations of highest soil mercury content according to19,20 and21. (Satellite imagery from Google Earth; photograph by S. Svanberg; Emperor Qin picture from Wikimedia Commons Qin_Shi_Huang_BW.png).

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Measurement System

The lidar system, which is described in detail in23, is, depending on atmospheric conditions, capable to map the concentration of atomic mercury out to a range of about 1 km, and can have a concentration sensitivity approaching typical Atlantic background levels of mercury, thus putting us in a good position to observe any anomalies. Generally speaking, the conditions for reaching a high sensitivity in absorption spectroscopic measurements are explained by the common Beer-Lambert law, which states that a high transition probability, such as for mercury, is always favourable, and that a low concentration can be compensated by a long distance over which the absorption is evaluated. Elevated concentrations, such as those found in our experiments, are needed to allow a reasonable range resolution, taking advantage of the differential absorption lidar concept. The site under study, being close to a major Chinese city, was found to have a general elevated mercury pollution level, on top of which hotspots related to the tomb were to be identified. The mercury concentrations measured allowed the use of an effective range resolution of 30 meters.

Our system, built with inspiration from a Swedish mobile system24, is based on a Jiefang truck, carrying a   ×  ×  m3 laboratory container. Narrow-band pulsed laser radiation at the mercury absorption wavelength close to  nm, was generated by a frequency-doubled dye laser, pumped by  nm radiation from a Nd:YAG laser operating at 20 Hz repetition frequency. The energy of the UV laser pulses used for pumping was up to mJ, and with the dye Coumarin dissolved in ethanol, green pulses at  nm were generated, which after frequency doubling yielded up to 15 mJ in 10 ns pulses at the relevant mercury wavelengths and with a linewidth better than  cm−1.

The wavelength was switched, alternating between a wavelength (λon) at  nm, where mercury has maximum absorption and a nearby, non-absorbed reference wavelength (λoff) at  nm while avoiding interference from near-by molecular oxygen lines. Detailed spectroscopic considerations regarding the overlapping structure of hyperfine and isotope-shift components, all pressure broadened into a quite smooth atmospheric pressure line, as well as regarding the molecular oxygen close-lying lines, can be found in ref. 25 The two wavelengths are sufficiently close so that a single frequency-doubling crystal at a fixed phase-matching angle could efficiently be used for both wavelengths. The frequency of every laser pulse was measured with a precision wavelength meter (Highfinesse WS-6), the output of which was fed back to a piezo actuator in the dye laser, in this way stabilizing the laser frequency in a closed-loop circuit. The linewidth and wavelength stability were ascertained by measurements on narrow oxygen absorption lines as detailed in ref. 23,25.

Back-scattered light is collected by a vertically looking 40 cm Newtonian telescope, over which a computerized folding mirror is placed to allow spatial scans. Signals for the on- and off-wavelengths are averaged in separate memories, and finally, the signals are divided resulting in a ratio curve. A slope of this curve reveals a mercury concentration15, with higher slopes corresponding to higher concentrations, which follows as a direct reflection of the well-known Beer-Lambert law. The differential absorption cross section *10−14 cm2/atom was employed in the spectroscopic evaluation of mercury concentrations23. It should be mentioned, that the validity of this process was assessed in an independent inter-calibration campaign of our remote-sensing system towards a conventional point monitor (Lumex RAM), used in the large global mercury research community, with satisfactory agreement as reported in ref. 7 The absorption cross section has a temperature and pressure dependence, but since the temperature influences only with a square root dependence, and since the elevation of Xi’an is only  m, the correction to actual conditions is negligible compared to other error sources. Also, considering that the wavelength separation between on two wavelengths used in the DIAL measurements is very small, the lidar curve division to obtain the DIAL curve becomes free of errors due to any differential effects in the particle backscattering.

Measurements and Results

In searches for mercury concentration anomalies around the mausoleum, the laser beam was scanned above the profile of the mound as indicated in the inset in the upper left part of Fig. 2, with the beam at a closest distance of about 5 m from the mound, which is mostly planted with pomegranate trees. An example of recorded data obtained from measurement point #1 with the laser beam directed just above the top of the mound is shown in Fig. 3(a–c). Figure 3(a) is a direct recording of the lidar backscatter signal, while (b) is a magnification of the signal from the range interval – m. The DIAL signal ratio curve is shown in Fig. 3(c), where a clear slope is shown, with a particularly strong feature at a range of about  m, indicating elevated mercury concentrations. The data were obtained by averaging pairs of on/off wavelength pulses during a time of about 1 minute. At far range, the curve becomes noisier, reflecting the fact that the backscattered intensity falls off with an inverse range-squared dependence. The raw DIAL curve is shown as a blue line. The red line, used for the concentration evaluation, is obtained by smoothing the DIAL curve in applying a sliding averaging over a 30 m range. Most of our measurements were performed at nighttime, when ambient light level is low. In this way the background in our optical recordings was reduced and signal-to-noise levels were improved. In principle, at  nm, no ambient radiation is present due to the absorption of stratospheric ozone with a cut-off at  nm, but some daylight leaked through the interference filter used in front of the detector. Since ozone absorption is unstructured, no influence on our mercury measurements from possible tropospheric ozone is experienced. The attainable measurement range was limited to about  m, since the short-wavelength light is strongly attenuated by scattering in the misty atmosphere connected to high temperature and general levels of particulate pollution. Longer ranges as indicated in the introduction, are achievable in clear atmosphere conditions, allowing better laser beam penetration. Data evaluation is normally initiated at a range of  m, since for closer ranges small laser beam overlap deviations as well as possible saturation of the atomic transition can degrade the data accuracy.

Data for atomic mercury monitoring at the Emperor Qin mausoleum. Panels (ad) correspond to measurement location #1, (eh) to location #2, and (il) to location #3. Curves (a,e,i) are recorded lidar backscattering signals, (b,f,j) are magnified sections of the curves, where recordings for on- and off-absorption wavelengths close to  nm are shown individually in red and blue, respectively. DIAL curves, obtained by dividing on- by off-resonance recordings are finally shown in (c,g,k). These curves would have a constant value of (apart from noise) for all ranges in the absence of atmospheric atomic mercury, but are in fact sloping, where a larger slope corresponds to a higher gas concentration. Mercury concentration maps over the mound are shown in panels (d,h,l), as obtained from locations #1, #2, and #3, with the concentrations given in ng/m3 and color-coded, to be evaluated against the color scales to the right of the maps. Here also the measurement directions corresponding to the individual data shown to the right of each map are indicated by yellow dashed lines. Since the maps are generated by averaging over several DIAL curves of the type shown in (c,g,k), the colored map data along the yellow lines are not fully matching the individual raw data curves shown.

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Evaluated averaged concentrations based on recordings of the type shown in Fig. 3(c) from full scans over the mound are shown in Fig. 3(d), where the measurement direction corresponding to Fig. 3(c) is specially indicated by a yellow dashed line. The curve exhibits a weak over-all slope indicating a background concentration of about 5–10 ng/m3 and an elevated concentration of about 23 ng/m3 on the western slope, close to the mound top platform. Elevated concentrations are also noted on the eastern slope, slightly towards the south. A full scan, comprising about 60–80 individual measurement directions, took about 4 hours, including the time for data transfer, mechanical movement of the scanning dome between the measurement directions, and spatially adjusting the somewhat complex scan, with an upward slope, a flat top section followed by a downward slope. The data from three such scans were then processed into the concentration map shown in Fig. 3(d). The average wind speed and direction during the data recording, as evaluated from the weather station on the top of the mound, were  m/s and coming in from the East-North-East.

Data recorded from measurement position #2 as indicated in Fig. 2 are shown in Fig. 3(e–h). The concentration map obtained from this position as averaged over two complete scans over the mound is shown in Fig. 3(h). We again note an area with elevated concentrations on the western slope, now raising to about 22 ng/m3 in a typical surrounding level of about 5–10 ng/m3. A further area with elevated concentration is noted close to the southern base. Average wind data during the recording were  m/s from the East-North-East.

Finally, data from measurement site #3 are shown in Fig. 3(i–l). Again, the concentration map was the result of two full scan. No evident concentration hotspots were observed in this case, with highest concentrations reaching 10 ng/m3.The average concentration over the total area of the mound was 6 ng/m3. During the recording of the data from site #3, the average wind data were  m/s, again from the East-North-East. This is higher by a factor of two than for the maps shown in Fig. 3(d,h) (the wind speeds there were and  m/s, respectively), and leads to a corresponding strong dilution of a localized mercury emission, which fully explains the absence of hotspots in this case. When the wind speed increases by a factor of two, the concentration due to a localized source is reduced by a factor of two, since the emission flux is the same. Flux issues are further discussed below.

We note, that the generation of such concentration maps is not trivial, mainly since the atmosphere is changing and the concentrations are varying, requiring a substantial amount of range smoothing, through which spatial resolution is reduced. Thus, while increased and localized concentrations were observed at certain locations over the tomb, as exemplified in Fig. 3(d,h), the concentration values, averaged over time and area to lower values, they are still significantly elevated compared to the surrounding area, and especially high in the areas previously indicated as hot-spots19,20,21. Occasionally quite high concentrations were observed in individual recordings, such as shown in Fig. 3(c). The DIAL curve slope observed at  m distance, right over one of the suggested hotspots, corresponds to a concentration value of 27 ng/m3. Occasionally, during the measurement campaign, even higher concentrations were observed. We argue, that a high localized value (23 ng/m3) of atmospheric mercury, persistent in three averaging scans as shown in Fig. 3(d), can only be explained by a localized emission from the mound. This conclusion is reached, when considering all the aspects influencing the accuracy of the measurements, which at the measurement range pertaining to the hot-spots in Fig. 3(d,h) is estimated to be ± 5 ng/m3. The accuracy, which for a chosen evaluation range interval is strongly dependent on the signal-to-noise ratio in the DIAL curve data, is clearly considerably higher for shorter ranges in the mercury concentrations maps given in Fig. 3(d,h,l). As mentioned above, the general background concentration levels in the area were about 5–10 ng/m3 with a highest observed value, apart from the Qin mausoleum location, of 13 ng/m3, possibly related to a further archaeological feature (unpublished data), which should be further investigated.

The question if possible mercury pollution from the Qin tomb significantly influences the surrounding environment has been addressed by Jin et al.21, who performed measurement of mercury concentration in soils and water. The lidar technique can in principle measure the total flux of a gaseous pollutant out from a source or an area, by performing vertical scans downwind of the source. This has been effectively demonstrated for strong mercury emission sources such as chlor-alkali plants, which employ liquid mercury electrodes5. Then, the concentration as integrated over the full cross-section area of the emission plume, as defined by the laser scan, is first determined. The local concentration, with unit [kg/m3], is added up horizontally (unit [m]) and vertically (unit [m]) yielding the area-integrated value, with unit [kg/m3 x m x m] = [kg/m]. Finally, multiplying this value with the perpendicular wind velocity, with unit [m/s]), we can obtain the total flux, which has the expected unit [kg/s].

To estimate the total net flux of atmospheric mercury from the mausoleum is, however, much more challenging, since the concentrations are much lower, the ambient air already contains elevated and varying concentrations of mercury, and the wind field around the mound is complex and varying. Such vertical scan measurements were tried and revealed maximum concentrations up to 8 ng/m3 in the presence of wind speeds of 5 m/s (unpublished data). Flow from the detected hot spots led to lower maximum concentrations as diluted by the comparatively high wind speed (similar to the case of the mound measurements at site 3) and turbulence downwind from the mound. Also, because of the rather high general background concentration levels, an integrated downwind flux value would need to be subtracted by an integrated upwind, likewise very uncertain, flux value. Thus, our efforts did not lead to any reliable measurements of the net total outflux from the tomb. Instead, an extremely crude estimate of the flux was made as presented below.


Differential absorption lidar mapping of the atmospheric mercury concentrations around the mausoleum of the first Qin emperor was performed, as we believe, for the first time. Measurement ranges were up to meters. Elevated concentrations of mercury were noted around the mausoleum mound, with values raising to around 25 ng/m3 compared to ambient concentrations of typically 5–10 ng/m3. The estimated accuracy of our concentration measurements is about ± 5 ng/m3 at the range of the hot-spots, and better for closer ranges.

Areas of highest concentrations on the pyramid slopes show correlation with earlier findings of elevated soil mercury concentrations19,20,21. Based on the data presented in Fig. 3(d,h) with the experimentally determined size of the area of increased mercury concentration (about 10 ng/m3 excess concentration, above the ambient concentrations), the wind speed and direction, and very crudely assuming the mercury plume to uniformly extend up to 20 m above the surface of the mound, we estimate a flux of mercury out of the pyramid of about 5 *10−8 kg/s. Clearly, this number has a large uncertainly, maybe of a factor 2, but can be used as a starting point for a calculation example for speculations on possible amounts of deposited mercury in the tomb. If we make the extremely uncertain assumption of a constant rate of emission to air (at the amount inferred from our measurements) during the 6 warmest months of the year and during half the time span since the closure of the tomb, we obtain a total loss of mercury to air of the order of 1 ton of liquid mercury. Clearly, there are very large uncertainties in these estimations, but our findings add to the credibility of year-old records by historian Sima on the existence of large amounts of mercury in the Emperor Qin tomb10, also in view of estimates of the production capability of mercury at the times of Emperor Qin11,12.

We note that the surface soil content of mercury has earlier been used as a similar evidence. If we assume that the measured average concentrations of deposited mercury in the soil ( ppb19,20,21) to be representative for the earth masses in the whole mound, we would likewise get a number of about 1 ton of mercury. It has speculatively been suggested that the actual pattern of surface mercury on the mound would reflect the mercury distribution on the underground palace map of China. However, since the mercury vapor distribution in the underground palace would be uniform, irrespective of the detailed localizations of liquid mercury, such claims would be unwarranted. Our present measurements on gaseous mercury further show, that the Emperor Qin mausoleum does not contribute in a significant way to the atmospheric mercury concentrations in the area, similarly as the water and soil mercury levels in the surrounding areas were found not to be significantly elevated21. The successful observation of weak mercury emission due to a deep-lying underground source also illustrates a potential for using mercury as a tracer gas for natural resource prospecting1,8,9, which is intended.

Our observations of leaks out of an underground chamber, intended to be intact and sealed “forever” for in- and out-flux, bring the current quests of constructing a suitable underground permanent deposit of nuclear waste to mind26,27,28,29. A US facility for weapon-related waste, WIPP (Waste Isolation Pilot Plant) is operating, but not without problems30. Sweden and Finland have facilities in construction (in Östhammar and Posiva, respectively), and further countries are in different project stages. Abundant fission products like 90Sr and Cs have medium half-lives of tens of years, while long-lived isotopes such as 93Zr and Cs have a half-life above one million years. Like for the ancient constructors at Xi’an, the task is now to ensure a secure enclosure, unaffected by possible geophysical events. An artist’s conception of the two scenarios is presented in Fig. 4. Leaking radioactive compounds would be detectable using the radioactivity itself, including the associated radon gas. So far, the nuclear waste is largely stored on the power plant sites waiting for the construction of suitable final deposit sites. Our study shows that leakage of dangerous material from an underground storage site can be a reality in a time span of years, even if great precautions were taken to seal the tomb. Regarding final storage of radioactive material, there is a widespread public doubt – possibly unwarranted - that present day engineering could achieve a completely safe solution, which is hampering constructions, leaving the general long-term nuclear waste storage a still somewhat open issue. Different time epochs have their own geophysical challenges to handle.

Emperor Qin’s tomb and future long-term storage of nuclear waste – the issue of constructing a “permanent” enclosure – an artist’s conception.

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The authors gratefully acknowledge the continuing support from Sailing He, Guofu Zhou, and Katarina Svanberg of South China Normal University, and the early assistance by Chunsheng Yan and Gabriel Somesfalean of Zhejiang University and Liang Mei of Lund University. The project was financially supported by a Guangdong Province Innovation Research Team Program (No. D) and the Guangdong Provincial Key Laboratory of Optical Information Materials and Technology (Grant No. B). Open access funding provided by Lund University.

Author information

Author notes
  1. These authors contributed equally: Guangyu Zhao and Weixing Zhang.


  1. Center for Optical and Electromagnetic Research, South China Academy of Advanced Optoelectronics, South China Normal University, University City Campus, Guangzhou, , China

    Guangyu Zhao, Zheng Duan, Ming Lian, Yiyun Li, Shiming Zhu & Sune Svanberg

  2. Emperor Qin Shihuang’s Mausoleum Site Museum, Xi´an, , China

    Weixing Zhang & Ningbin Hou

  3. Department of Physics, Lund University, SE 00, Lund, Sweden

    Sune Svanberg


S.S. planned the study, supervised all aspects of the project and wrote most of the manuscript. G.Y.Z., M.L., Y.Y.L., Z.D. and S.M.Z. performed the measurements. G.Y.Z. evaluated the data and prepared the figures in collaboration with S.S. W.X.Z. and N.B.H. provided on-site infrastructure and archaeological expertise. All authors approved the final manuscript.

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Correspondence to Sune Svanberg.

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Floating an Anvil on Liquid Mercury

The Secret Tomb of China's 1st Emperor: Will We Ever See Inside?

Buried deep under a hill in central China, surrounded by an underground moat of poisonous mercury, lies an entombed emperor who's been undisturbed for more than two millennia.

The tomb holds the secrets of China's first emperor, Qin Shi Huang, who died on Sept. 10, B.C., after conquering six warring states to create the first unified nation of China.

The answers to a number of historical mysteries may lie buried inside that tomb, but whether modern people will ever see inside this mausoleum depends not just on the Chinese government, but on science.

"The big hill, where the emperor is buried — nobody's been in there," said archaeologist Kristin Romey, curatorial consultant for the Terracotta Warrior exhibition at New York City’s Discovery Times Square. "Partly it's out of respect for the elders, but they also realize that nobody in the world right now has the technology to properly go in and excavate it."

The Terracotta Warrior exhibition, featuring artifacts from the Qin dynasty and nine life-size statues from the extended burial complex built for Qin Shi Huang, is on display through Aug. [Photos: Terracotta Warriors Protect Secret Tomb]

The warring states

Qin Shi Huang (pronounced "chin shuh hwang") was born in B.C., first son to the king of Qin, one of six independent kingdoms inside modern China. These kingdoms had been warring for more than years, but through a combination of military strength, strategy and natural disasters, Qin Shi Huang conquered them all, proclaiming himself not just a king, but also an emperor — the first of China.

Scholars still debate the details of how this occurred, and what unique tactics allowed the Qin emperor to achieve what no one had managed before.

When he died, Qin Shi Huang was buried in the most opulent tomb complex ever constructed in China, a sprawling, city-size collection of underground caverns containing everything the emperor would need for the afterlife. The ancient Chinese, along with many cultures including ancient Egyptians, believed that items and even people buried with a person could be taken with him to the afterlife.

But instead of burying his armies, concubines, administrators and servants with him, the Qin emperor came up with an alternative: clay reproductions.

Shocking discovery

In , a group of farmers digging wells near Xi'an, China stumbled upon one of the most shocking archaeological discoveries of all time. The life-size terracotta solider they dug out of the ground turned out to be just one of an army of thousands, each utterly unique, with individual clothing, hair and facial features.

For almost four decades, archaeologists have been excavating the site. So far, they've uncovered about 2, clay soldiers, but experts estimate there are more than 8, in total.

"They're going to be digging there for centuries," Romey predicted.

Still, scientists have yet to touch the central tomb, which holds a palace containing the body of Qin Shi Huang.

"It's really smart what the Chinese government is doing," Romey told LiveScience. "When we went into [Egyptian King] Tut's tomb, think about all the information we lost just based on the excavation techniques of the s. There's so much additional that we could have learned, but the techniques back then weren’t what we have now."

"Even though we may think we have great archaeological excavation techniques right now," she said, "who knows, a century down the road if we open this tomb, what they're going to say?"

To open the tomb?

The decision whether to explore the tomb anytime soon, or ever, is up to the government of China. That decision will likely be influenced by the pace of technological progress.

"In archaeological conservation, every year you have major new developments," Romey said. "When we began excavating [the soldiers] in the '70s, the minute they were exposed to air and sunlight, the pigment just flaked off. Now they’ve figured out a new technique where they can actually preserve the paint as they excavate."

Perhaps, if science advances enough, that excavation wouldn't cause serious damage to the burial site, and the tomb will finally be opened. [Album: The Seven Ancient Wonders of the World]

"I wouldn’t be surprised if you had some sort of robotic visual survey going in there at some point," Romey said.

And despite their desire to protect the treasures of antiquity, archaeologists are itching with curiosity to find out what's inside Qin Shi Huang's central tomb.

Rivers of mercury

Ancient writings say the emperor created an entire underground kingdom and palace, complete with a ceiling mimicking the night sky, set with pearls as stars. Pits full of terracotta concubines have never been discovered, though experts predict they exist somewhere in the complex.

And Qin Shi Huang's tomb is also thought to be encircled with rivers of liquid mercury, which the ancient Chinese believed could bestow immortality.

"It's kind of ironic," Romey said. "This is probably how he died, by ingesting mercury. He was taking all these mercury pills because he wanted to live forever and it killed him by the age of "

That moat of mercury also presents another reason why archaeologists are loath to explore the tomb just yet — doing so would likely be very dangerous, according to soil samples around the tomb, which indicate extremely high levels of mercury contamination.

In the end, scientists and historians must always weigh their desire to know more with the damage such inquiry would cause.

"Archaeology, ultimately, is a destructive science," Romey said. "You have to destroy stuff in order to learn about it."

Follow Clara Moskowitz on Twitter @ClaraMoskowitz or LiveScience @livescience. We're also on Facebook & Google+.

Clara has a bachelor's degree in astronomy and physics from Wesleyan University, and a graduate certificate in science writing from the University of California, Santa Cruz. She has written for both and Live Science.

Of mercury china lake

The famous terracotta warriors are only a part of the gigantic mausoleum of Qin Shi Huang, the first emperor of unified China, who reigned between and BC.

In fact, the complex, located 30 kilometers east of Xian in the northwest of the country, houses more than tombs covering the impressive area of 60 square kilometers. More than half a million workers worked there for 38 years, following a detailed plan to replicate the entire known China.

The main chamber, where the emperor&#;s tomb is, has never been opened. The Chinese government, on the recommendation of archeologists working on the site, does not allow it to be opened and examined until they have the technology to safely prevent whatever is inside from being damaged. It may take years, decades or centuries for that to happen.

But then, how do we know what&#;s inside the tomb? The answer is called Sima Qian. The so-called father of Chinese historiography lived between and 86 B.C. and wrote a general history of the kingdom covering more than 2, years in retrospect from his own time.

Known as Shiji (Historical Records), it had been started by his father Sima Tan, and Qian completed it in 91 BC, about five years before his death. It tells the story of the construction of the great mausoleum, the burial of the terracotta warriors and provides concise data, such as the number of , workers involved in the colossal work.

When his writings were examined by Western historians they were taken with much scepticism, as exaggerations and even mythical legends without historical basis. This was partly justified because Qian often presents legendary and even mythological figures from China&#;s history as historical facts, assigning them precise chronologies.

However, archaeological discoveries in recent decades have confirmed many of the Shiji&#;s claims, such as the terracotta warriors and the location of other rulers&#; graves. So Qian&#;s claims are taken very cautiously today, hence the reluctance to open Qin Shi Huang&#;s tomb.

Because no one knows exactly what&#;s inside, but Sima Qian says that in the great underground palace, which is larger than a football field, there is a reproduction on a scale of China as known at the time. Including over a hundred rivers, lakes and seas. A kind of microcosm where large amounts of mercury would have been used instead of water to simulate the flow of rivers.

Is it possible that Sima Qian is right about this too? In the s, researchers at China&#;s Institute of Geophysical and Geochemical Exploration found that the soil surrounding the tomb contains considerably higher concentrations of mercury than the rest of the region. While in remote locations the soils contained an average of 30ppb (parts per billion) of mercury, the average over the vault was ppb, and in some sites it was as high as ppb. Some of the archaeologists working at the site believe that this is a very feasible possibility.

Especially when the last tests carried out to measure soil resistivity revealed an intriguing feature of the terrain. A phase anomaly that occurs when an electrical current is reflected by a conductive surface, such as metal.

In addition, analysis of the distribution of mercury levels revealed that it was highest in the northeast, and then in the south, while the northwest corner had very low levels. Overlaying this distribution on a map of China curiously coincides with the location of China&#;s two great rivers, the Yellow and the Yangtze, seen from the ancient capital Qin, about 30 kilometers from the monument.

According to Yinglan Zhang, who led the excavations from to , there should be many other cultural artifacts and relics buried in the main chamber and in other tombs around it, possibly things that are beyond our imagination. But he also believes that the distribution of mercury may not be a reliable indicator. The chamber may have collapsed thousands of years ago, just as the graves containing the terracotta army did. The mercury may have volatilized and drained through the soil for centuries.

It should be noted that the terracotta warriors were found outside the 2 km wall surrounding the main chamber. Inside the wall were found buildings that contained food and other objects that the emperor might need in the afterlife. It is also possible that the emperor was not buried alone. Sima Qian claims that many officers were buried with him, although it is not clear whether they were alive or dead at the time. Many of these buildings and objects could have been gilded using gold and silver diluted in mercury as a pigment, a common practice at the time.

If it were the case that the mercury detected had been used for these decorative purposes, specialists doubt that there would be a large quantity. Based on estimates of mercury production in the Song era, they believe that at most we would be talking about around tonnes, approximately 7 cubic metres. We may never know the secrets of the tomb of Emperor Qin Shi Huang.

Sources: Chemistry World / Science and Civilisation in China (Joseph Needham) / Chinese refuse to open the mysterious tomb of their first emperor and the remaining 6, terracotta soldiers / The Secret Tomb of China&#;s 1st Emperor: Will We Ever See Inside? / Wikipedia

Fascinating Facts About China's Terracotta Army

Discoveries May Rewrite History of China's Terra-Cotta Warriors

In the four decades since mysterious terra-cotta statues first came to light in northern China, archaeologists have uncovered a whole lifelike army. But that wasn’t the only secret hidden underground there. Stunning revelations are now rewriting the history of the great ruler who created this army as part of his final resting place. And a radical new theory even suggests that foreign artists trained his craftsmen.

Known today as the First Emperor, Qin Shi Huang Di left a legacy that would make him a towering figure in Chinese history. By the time he died in B.C., he had united warring kingdoms into one country, put an end to feudalism, and built the Great Wall that endures today as a monument to his power.

China's Terra-Cotta Warriors

The explore team visits the tomb of the Terra-Cotta Warriors and Horses, where there is a ceramic army of as many as 8, life-sized, intricately carved statues modeled after Emperor Qin's army.

But his most stunning project first came to light in when farmers uncovered strange figures while digging a well near the old Chinese capital of Xianyang. Excavations have since revealed sections of a grand funerary complex. Three huge pits harbor several thousand warriors, presumably meant to protect the emperor for eternity. These statues were unlike anything ever uncovered before in China. And that raises a big question: How could the royal artists have come up with such an idea?

terracotta acrobat

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Scientists have gathered a variety of provocative clues: Terra-cotta acrobats and bronze figures of ducks, swans, and cranes uncovered at the royal tomb complex may show evidence of Greek influence. And European DNA has been recovered from skeletons at a site in northwestern China.

Putting these together, experts have worked out a theory: Inspiration for the terra-cotta army may have come from foreign artists. Traveling from Hellenized areas of Western Asia and arriving in China 1, years before Marco Polo, they could have trained the local craftsmen who furnished the emperor’s tomb with statuary. (Learn more about how the terra-cotta warriors were made here.)

China's Megatomb Revealed

Scientists using remote sensing, ground-penetrating radar, and core sampling have also revealed the emperor’s tomb complex to be much larger than once believed—almost 38 square miles (some 98 square kilometers). At its heart stands a tall earthen mound that covers the ruler’s tomb, which remains sealed. Many other people were also buried at the site. Archaeologists have discovered mass graves that appear to hold the remains of the craftsmen and laborers—including convicted criminals in chains—who died during the three decades it took to create the royal mausoleum. Other mass burials seem to tell grisly tales of a brutal struggle to capture the emperor’s throne.

Chinese Game of Thrones

Despite the brilliance and power of the First Emperor, he was unable to make sure his eldest son succeeded him. It was a failure that had devastating consequences. Experts now believe it may have launched a bloodbath—and ultimately brought a swift end to the dynasty that Qin Shi Huang Di founded.

An account written in about 89 B.C. by Sima Qian, an official in the second dynasty, describes a time of deadly palace intrigue: One of the emperor’s many sons conspired with the chief eunuch to murder his oldest brother, the emperor’s presumed heir, and to seize the throne himself.

Now archaeologists have found tantalizing clues that the power grab was even more brutal than Sima Qian described. A group of skeletons was found with artifacts belonging to the royal family. These were mostly males, possibly the deceased emperor’s sons. One skull offers clues to their fate. It’s split by the metal bolt from a crossbow, likely shot at close range. Experts now believe these young princes may have been executed by their ambitious sibling who was trying to secure the throne for himself.

skull with the arrowhead

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In another area, very close to the emperor’s burial, archaeologists have identified a group of about a hundred tombs. But after excavating several, they’re still unsure of what they’ve found. The burial chambers are empty, and body parts lie strewn in the doorways along with a scattering of pearls and pieces of gold. Were these the royal concubines, buried near the deceased emperor to serve him in the next world as they had in this life? Or do these graves represent something sinister?

According to the account left by Sima Qian, the new emperor—the usurper—killed many of his father’s concubines. Sad as it may seem, that move would have made sense to someone whose claim to the throne was shaky. The usurper had already killed the heir apparent and also likely did away with other brothers who were potential rivals. But what if some of the concubines were pregnant? And what if one were to give birth to a boy who was then hidden, brought up in secret, trained to be a great warrior, and finally presented as a fully grown man able to overthrow his much older brother and take their father’s title and territories for himself?

In thinking through this worst-case scenario, there would have been no choice. The women had to die. But why their bodies were dismembered is unclear. Perhaps clues will turn up in the many burials that are still to be excavated.

concubine bones in dirt

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In the end, though, all the bloodshed was for naught. The usurper, Qin Er Shi, couldn’t begin to fill his father’s shoes. His rule lasted a mere three years, and his family’s dynasty was soon overthrown. The first emperor’s tomb surely holds many more surprises, but archaeologists have no plans to excavate it in the near future. Exposing fragile artifacts to air and light might damage them beyond repair, it’s feared, so the tomb will most likely stay buried until radically new conservation technologies are discovered in the future.

Sima Qian wrote that the emperor was laid to rest in a bronze coffin, and his burial chamber was filled with lavish grave goods—replicas of palaces, rivers of mercury, “rare utensils and wonderful objects.” But Sima Qian was writing more than a century after the first emperor’s death. Could he really have gotten all the details right?

Some of his statements seem too over the top to be true—that the emperor pressed , laborers and convicts into service to build his grand funerary landscape, for example. And Sima Qian seems to have skipped over some important features altogether, offering not one word about the creation of the terra-cotta army.

But in light of the evidence for royal murders before the unlikely succession of a very junior prince, it seems entirely possible that his description of the royal burial chamber is accurate—and that archaeologists will someday uncover Qin Shi Huang Di’s fabled trove of treasures.

China's Megatomb Revealed airs in the U.S. on Sunday, October 23, at 9/8c and globally on National Geographic Channel (excluding the UK) beginning Sunday, October


Now discussing:

Mausoleum of the First Qin Emperor

The Mausoleum of the First Qin Emperor (Qin Shi Huang) (Chinese: 秦始皇陵; pinyin: Qínshǐhuáng Líng) is located in Lintong District, Xi'an, Shaanxi province of China. This mausoleum was constructed over 38 years, from to BC, and is situated underneath a meter-tall tomb mound shaped like a truncated pyramid.[1] The layout of the mausoleum is modeled on the Qin capital Xianyang, divided into inner and outer cities. The circumference of the inner city is &#;km ( miles) and the outer is &#;km ( miles). The tomb is located in the southwest of the inner city and faces east. The main tomb chamber housing the coffin and burial artifacts is the core of the architectural complex of the mausoleum.

The tomb itself has not yet been excavated. Archaeological explorations currently concentrate on various sites of the extensive necropolis surrounding the tomb, including the Terracotta Army to the east of the tomb mound.[2] The Terracotta Army served as a garrison to the mausoleum and has yet to be completely excavated.[3][4]


Work on the mausoleum began soon after Emperor Qin ascended the throne in BC when he was still aged 13, although its full-scale construction only started after he had conquered the six other major states and unified China in BC. The source of the account of the construction of the mausoleum and its description came from Sima Qian in chapter six of his Records of the Grand Historian, which contains the biography of Qin Shi Huang:

In the ninth month, the First Emperor was interred at Mount Li. Digging and preparation work at Mount Li began when the First Emperor first came to the throne. Later, after he had unified his empire, , men were sent there from all over his empire. They dug through three layers of groundwater, and poured in bronze for the outer coffin. Palaces and scenic towers for a hundred officials were constructed, and the tomb was filled with rare artifacts and wonderful treasure. Craftsmen were ordered to make crossbows and arrows primed to shoot at anyone who enters the tomb. Mercury was used to simulate the hundred rivers, the Yangtze, Yellow River, and the great sea, and set to flow mechanically. Above were representation of the heavenly constellations, below, the features of the land. Candles were made from fat of "man-fish", which is calculated to burn and not extinguish for a long time. The Second Emperor said: "It would be inappropriate for the concubines of the late emperor who have no sons to be out free", ordered that they should accompany the dead, and a great many died. After the burial, it was suggested that it would be a serious breach if the craftsmen who constructed the mechanical devices and knew of its treasures were to divulge those secrets. Therefore after the funeral ceremonies had completed and the treasures hidden away, the inner passageway was blocked, and the outer gate lowered, immediately trapping all the workers and craftsmen inside. None could escape. Trees and vegetations were then planted on the tomb mound such that it resembles a hill.

—&#;Sima Qian, Shiji, Chapter 6.[5][6]

Some scholars believe that the claim of having "dug through three layers of groundwater" to be figurative.[7] It is also uncertain what the "man-fish" in the text refers to originally (in modern Chinese it means "mermaid"), interpretation of the term varies from whale to walrus and other aquatic animals such as giant salamander.[8][9]

Before the Mausoleum of the First Qin Emperor was completed, a peasant rebellion broke out during the late Qin dynasty. Zhang Han redeployed all the , people building the mausoleum to suppress the rebellion, so the construction of the mausoleum ceased. After Xiang Yu entered Xianyang, he was said to have looted the tomb. Afterwards, it is said that a shepherd unintentionally burnt down the tomb.[10] The story goes that he went into the dug pit of the mausoleum, dug by Xiang Yu, to look for his sheep with a torch in his hand, and a fire was started, burning away the tomb structures.[11][12] No solid evidence of the destruction of the tomb has been found, although evidence of fire damage has been found in the pits housing the Terracotta Army.[13] Some scholars think that the mausoleum did not suffer any large-scale destruction.

In , the mausoleum, including the Terracotta Warriors, was listed as World Heritage Sites.[14]

Discovery of the Terracotta Warriors[edit]

General view of the pit No. 1 in the museum of Xi'an

The first fragments of warriors and bronze arrowheads were discovered by Yang Zhifa, his five brothers, and Wang Puzhi who were digging a well in March in Xiyang, a village of the Lintong county.[15][16] At a depth of around two meters, they found hardened dirt, then red earthenware, fragments of terracotta, bronze arrowheads and terracotta bricks.[17] Yang Zhifa threw the fragments of terracotta in the corner of the field, and collected the arrowheads to sell them to a commercial agency. Other villagers took terracotta bricks to make pillows.[17] A manager in charge of the hydraulic works, Fang Shumiao, saw the objects found and suggested to the villagers that they sell them to the cultural centre of the district. Yang Zhifa received, for two carts of fragments of what would turn out to be terracotta warriors, the amount of 10 yuan.[17]Zhao Kangmin, responsible for the cultural centre, then came to the village and bought everything that the villagers uncovered, as well as re-purchasing the arrowheads sold to the commercial agency.

In May , a team of archaeologists from Shaanxi went to the site to undertake the first excavations of what would later be designated Pit 1. In May , Pit 2 was discovered by drilling and in July the Pit 3.[18] The excavations over an area of 20, square meters produced about 7, statues of terracotta warriors and horses, and about a hundred wooden battle chariots and numerous weapons.[18] Large structures have been erected to protect the pits; the first was finished in A larger necropolis of six hundred pits was uncovered by [19] Some pits were found a few kilometers away from the mound of the tomb of Emperor Qin Shi Huang.[17]

Archaeological studies[edit]

Chariot found outside of the tomb mound

The necropolis complex of Qin Shi Huang is a microcosm of the Emperor's empire and palace, with the tomb mound at the center. There are two walls, the inner and outer walls, surrounding the tomb mound, and a number of pits containing figures and artifacts were found inside and outside the walls. To the west inside the inner wall were found bronze chariots and horses. Inside the inner wall were also found terracotta figures of courtiers and bureaucrats who served the Emperor. Outside of the inner wall but inside the outer wall, pits with terracotta figures of entertainers and strongmen, as well as a pit containing a stone suit of armour were found. To the north of the outer wall were found the imperial park with bronze cranes, swan and ducks with groups of musicians. Outside the outer walls were also found imperial stables where real horses were buried with terracotta figures of grooms kneeling beside them. To the west were found mass burial grounds for the labourers forced to build the complex. The Terracotta Army is about &#;km east of the tomb mound.[20][21]

The tomb mound itself at present remains largely unexcavated, but a number of techniques were used to explore the site. The underground palace has been located at the center of the mound. Archaeological survey and magnetic anomaly studies indicate a 4-meter high perimeter wall, measuring meters north to south and meters east to west, which is made of bricks and serves as the wall of the underground palace. On top is an enclosing wall made of rammed earth of 30–40 meters in height. There are sloping passageways leading to the four walls. The west tomb passage is linked to a pit where the bronze chariots and horses were found. The tomb chamber itself is 80 meters long east to west, 50 meters north to south, and is about 15 meters high.[22] There are, however, disagreements among the academic community about the depth at which the palace lies, with estimates ranging from 20 meters to 50 meters.

According to the scientific exploration and partial excavation, a significant amount of metal is present in the underground palace which has a very good drainage system. Sima Qian's text indicates that during its construction the tomb may have reached groundwater, and the water table is estimated to be at a depth of 30 meters. An underground dam and drainage system was discovered in and the tomb appeared not to have been flooded by the groundwater.[22] Anomalously high levels of mercury in the area of the tomb mound have been detected,[22]:&#;&#; which gives credence to the Sima Qian's account that mercury was used to simulate waterways and the seas in the Mausoleum of the First Qin Emperor. However, some scholars believe that if the underground palace is excavated, the mercury would quickly volatilize. "A Preliminary Study of Mercury Buried in the Mausoleum of the First Qin Emperor", an article published in Archaeology magazine, Volume 7, says that during the measuring of soil mercury content, one measured point reached parts per billion; the rest of 53 points reached an average content of around ppb. There is also a claim that the mercury content is actually a result of local industrial pollution. It is reported in "Lintong County Annals" that from to , according to general investigation on workers involved with benzene, mercury and lead, people from 21 factories were found poisoned."[23]

In December , it was announced that the remains of an "imperial palace" of great size had been found at the site.[24] Based on its foundations, the courtyard-style palace was estimated to be meters long and meters wide, covering an area of , square meters, which is nearly a quarter of the size of the Forbidden City in Beijing. The palace included 18 courtyard houses and a main building that overlooked the houses. The archaeologists have been excavating the foundations since and have found walls, gates, stone roads, pottery shards and some brickwork.[25]

Opinions on possible excavation[edit]

Outlines of various pyramids overlaid on top of on another to show relative height
Comparison of approximate profiles of the Mausoleum of the First Qin Emperor with some notable pyramidal or near-pyramidal buildings. Dotted lines indicate original heights, where data is available. In its&#;SVG&#;file, hover over a pyramid to highlight and click for its article.

Beginning in , various scholars proposed to explore the underground palace, citing the following main reasons:

  • The Mausoleum of the First Qin Emperor is in a seismic zone, so underground cultural relics need to be unearthed for protection;
  • to develop tourism; and
  • to prevent grave robbery.[26]

However, opponents of such excavations hold that China's current technology is not able to deal with the large scale of the underground palace yet. For example, in the case of the Terracotta Army, the archaeologists were initially unable to preserve the coat of paint on the surface of terracotta figures, which resulted in the rapid shedding of their painted decoration when exposed to air.[27][28] The State Administration of Cultural Heritage (SACH) indicated that research and evaluations should be conducted first so as to develop a protection plan for the underground palace, and rejected a proposal by archaeologists to excavate another tomb close by thought to belong to the Emperor's grandson over fears of possible damage to the main mausoleum itself.[29]


  1. ^Portal, Jane. "The first emperor of China: new discoveries & research: later this month the British Museum unveils an unprecedented loan exhibition of the terracotta warriors and other discoveries made at the 3rd-century BC tomb complex of Qin Shihuangdi, China's first emperor. Jane Portal, the exhibition's curator, explains the importance of the new finds." Apollo Sept. 54+. Academic OneFile. Web. 11 July
  2. ^Liu Yuhan (30 April ). "New York City welcomes the Terracotta Warriors". China Daily. Retrieved 13 July
  3. ^"Terra Cotta Warriors: Guardians of China's First Emperor".
  4. ^Li Xianzhi (13 October ). ""Teenage warriors" discovered in China's terracotta army". Xinhua News Agency. Retrieved 13 July
  5. ^司马迁 (). 史记. 卷六.秦始皇本纪: 中华书局. ISBN&#;.
  6. ^Chinese Text ProjectShiji, original text: 九月,葬始皇泰山。始皇初即位,穿治酈山,及并天下,天下徒送詣七十餘萬人,穿三泉,下銅而致槨,宮觀百官奇器珍怪徙臧滿之。令匠作機弩矢,有所穿近者輒射之。以水銀為百川江河大海,機相灌輸,上具天文,下具地理。以人魚膏為燭,度不滅者久之。二世曰:「先帝后宮非有子者,出焉不宜。」皆令從死,死者甚眾。葬既已下,或言工匠為機,臧皆知之,臧重即泄。大事畢,已臧,閉中羨,下外羨門,盡閉工匠臧者,無復出者。樹草木以象山。
  7. ^Portal, Jane (). The First Emperor: China's Terracotta Army. Harvard University Press. ISBN&#;.
  8. ^"史记·卷六&#; 十二本纪 秦始皇本纪第六".
  9. ^Charles Higham (). Encyclopedia of Ancient Asian Civilizations. Facts on File. p.&#; ISBN&#;.
  10. ^Tanner, Harold M. (). China&#;: a history. Indianapolis: Hackett Pub. Co. p.&#; ISBN&#;.
  11. ^Zhewen, Luo (). China's imperial tombs and mausoleums (1&#;ed.). Beijing: Foreign Languages Press. ISBN&#;.
  12. ^Han Shu《汉书·楚元王传》:Original text: "项籍焚其宫室营宇,往者咸见发掘,其后牧儿亡羊,羊入其凿,牧者持火照球羊,失火烧其藏椁。" Translation: Xiang burned the palaces and buildings. Later observers witnessed the excavated site. Afterward a shepherd lost his sheep which went into the dug tunnel; the shepherd held a torch to look for his sheep, and accidentally set fire to the place and burned the concealed coffin.
  13. ^"China unearths new Terracotta Warriors". BBC News. 12 May Retrieved 3 December
  14. ^"Mausoleum of the First Qin Emperor". UNESCO World Heritage Centre. Retrieved 9 June
  15. ^Yu Fei (29 September ). "Living with the Terra-cotta Army". Archived from the original on 18 March Retrieved 25 May
  16. ^Glancey, Jonathan (12 April ). "The Army that Conquered the World". BBC.
  17. ^ abcdZhang Zhongli (), p.
  18. ^ abZhang Zhongli (), p
  19. ^Danielle Elisseeff , p.&#; harvnb error: no target: CITEREFDanielle_Elisseeff (help).
  20. ^Anthony Barbieri-Low. "The Necropolis of the First Emperor of Qin – Excerpt from lecture in History Ancient China". University of California, Santa Barbara. Archived from the original on 20 November
  21. ^"The First Emperor – China's Terracotta Army"(PDF). British Museum.
  22. ^ abcDuan Qingbo (). "Scientific Studies of High Level of Mercury in Qin Shihuangdi's Tomb". In Jane Porter (ed.). The First Emperor: China's Terracotta Army. Harvard University Press. pp.&#;– ISBN&#;.
  23. ^常勇; 李同 (). "泰始皇陵中埋藏汞的初步研究". 考古.
  24. ^""Imperial palace" found at first Chinese emperor's cemetery". Xinhuanet. 1 December Retrieved 3 December
  25. ^Jonathan Kaiman (3 December ). "China unearths ruined palace near terracotta army". The Guardian. Retrieved 3 December
  26. ^Ma Lie (27 November ). "Nine held over tomb robbery in Xi'an". China Daily. Retrieved 13 July
  27. ^Ma Lie (19 May ). "More Terracotta Warriors rise from the earth". China Daily. Retrieved 13 July
  28. ^Ma Lie (9 September ). "Terracotta army emerges in its true colors". China Daily. Retrieved 13 July
  29. ^Tang Danlu (26 February ). "No excavation for mysterious tomb near Qinshihuang Mausoleum". Xinhua News Agency. Retrieved 13 July

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