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Hezheng Mammalian Fossil Sites of Gansu

Date de soumission : 17/05/2024
Critères: (viii)
Catégorie : Naturel
Soumis par :
Permanent Delegation of China to UNESCO
État, province ou région :
Hezheng County and Dongxiang County, Linxia Hui Autonomous Prefecture, Gansu Province
Coordonnées 103° 16' 42.866"-103° 29' 03.061"E,35° 20' 56.201" -35° 39' 53.631"N
Ref.: 6768
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Description

(1) Indricotheriinae Fauna Fossil site -1 at Yagou-Tala
Indricotheriinae Fauna Fossil site -2 at Yagou-Tala
103° 16' 46.476" E 35° 38' 43.414" N
103° 19' 36.881" E 35° 38' 10.333" N

(2) Platybelodon Fauna Fossil site at Laogou
103° 24' 55.927" E 35° 28' 19.826" N

(3) Hipparion Fauna Fossil site at Hualin
103° 25' 14.131" E 35° 21' 19.102" N

(4) Equus Fauna Fossil site at Longdan
103° 28' 59.547" E 35° 31' 33.882" N

(5) Geological Section at Maogou
103° 19' 01.275" E 35° 39' 49.418" N

The nominated property is located in the Linxia Basin at the intersection of the northeastern edge of the Qinghai-Tibet Plateau and the Loess Plateau. It is located about 100 kilometers south of Lanzhou City, Gansu Province and is part of the Longzhong Basin. The Linxia Basin is located at the intersection of three natural zones: the eastern monsoon zone, the western arid zone and the alpine zone of the Qinghai-Tibetan Plateau. Geomorphologically, it is located in the transition zone between the first terrain step and the second terrain step in mainland China. The entire territory belongs to the north temperate continental climate zone, with an average annual sunshine of 2457 hours, a frost-free period of 133 days, and an average annual temperature of 5°C.

The terrain of the nominated area is high in the south and low in the north. The highest peak of the Taizishan Mountain in the south is 4368m above sea level, and the north is close to the center of Linxia Basin, with the lowest elevation of 1900m. The open area of the valley is about 2200m above sea level.

Linxia basin is a foreland basin in the northeastern edge of the Qinghai-Tibet Plateau, which was formed during the Cenozoic uplift of the Plateau. The Linxia basin developed and exposed continuous late Cenozoic terrestrial facies deposits from Oligocene red beds to Holocene loess (about 30 million to 10,000 years ago). It is one of the most complete late Cenozoic terrestrial biostratigraphic sections in Eurasia, which is rich in mammalian fossils.

There are numerous fossil sites in the nominated property. The sites with the most abundant mammalian fossils are located in Hezheng County, Guanghe County and Dongxiang County in the Linxia Basin of Gansu, represented by the Indricotheriinae Fauna of late Oligocene, the Platybelodon Fauna of middle Miocene, the Hipparion Fauna of late Miocene and the Equus Fauna of early Pleistocene. It is among the most famous fossil sites in China. So far, more than 40,000 fossil specimens have been excavated from more than 100 fossil sites in Hezheng area. This makes Hezheng one of the regions with the richest mammalian fossils in China and even the whole Eurasia (and one of the richest regions in the world). The vertebrate fossils found in Hezheng include reptiles, birds and mammals, which belong to more than 17 orders and 250 genera and species, including more than 80 new genera and species, and the geological time scale ranges from 30 Ma to 2 Ma. Among them, the Hipparion Fauna preserved at Hualin area of Hezheng is the most representative, and a large number of mammalian fossils excavated from the sites are the best specimens for further study on the Hipparion Fauna, which are irreplaceable in the world. Therefore, the area where the nominated property is located has become a hot spot for the study on geology, geomorphology, flora and Fauna succession, as well as climate and environmental changes relative to the Qinghai-Tibet Plateau. Research institutions have published thousands of academic research works based on geological research carried out in this area.

In Linxia basin, the fossil sites at Yagou-Tala belong to the Jiaozigou stratigraphic formations of late Oligocene, corresponding to the Indricotheriinae Fauna. The fossil site at Laogou belongs to the Laogou stratigraphic formations of the middle Miocene, corresponding to the Platybelodon Fauna. The fossil site at Hualin belongs to the Liushu stratigraphic formations of the late Miocene, corresponding to the Hipparion Fauna. The fossil site at Longdan belongs to the Wucheng stratigraphic formations of the early Pleistocene, corresponding to the Equus Fauna. Maogou Section belongs to Tala stratigraphic formations of the early Oligocene, corresponding to the Indricotheriinae Fauna. The above-mentioned four fossil relic sites and one section fully reflect the succession processes of four mammalian Fauna in the hinterland of Asia in the wake of the Qinghai-Tibet Plateau uplift since the late Pleistocene, and are one of the most complete examples of late Cenozoic terrestrial biostratigraphy in Eurasia. Thus, the above four fossil sites (Yagou-Tala, Laogou, Hualin and Longdan) and one section (Maogou) are identified as heritage nomination properties.

Each component of the nominated property is described as follows:

(1) The Indricotheriinae Fauna Fossil site at Yagou-Tala

This fossil site is located at Yagou, Dongyuan Township, Dongxiang County and its surrounding areas. It is the representative site of Paraceratherium sp. Fauna fossils, and 10 taxonomies of mammalian fossils have been excavated. The fossil layer of the Indricotheriinae Fauna Fossil site at Yagou is brownish yellow sandstone and sandy gravel, which belongs to the strata of the late Oligocene. Abundant mammalian fossils have also been excavated from this site, including Ardynia altidentata sp. nov.. The fossil layer of the Indricotheriinae Fauna Fossil site at Tala is purplish red siltstone and mudstone, which also belongs to the strata of the late Oligocene. And fossils of Indricotheriinae fauna have been excavated from this site, such as Paraentelodon macrognathus and Paraceratherium sp..

(2) The Platybelodon Fauna Fossil site at Laogou

The fossil site is located about 2 kilometers northeast of Hezheng County, and a large number of middle Miocene Platybelodon Fauna fossils (Proboscidea takes first, Rhinocerotidae comes second.) have been discovered.

(3) The Hipparion Fauna Fossil site at Hualin

Located at Hualin 11 kilometers away from Hezheng County, this fossil site is the most important fossil site in Hezheng area, and it is also the only fossil site in the region which is exposed (not in the excavation tunnels). The fossils are concentrated, rich in species and abundant in quantity, and a large number of Hipparion Fauna fossils have been found. Among them, Hipparion sp., Chilotherium sp. and other skull fossils are well preserved. This site is an excellent place for scientific research on paleontological fossils and their geological relics.

(4) The Equus Fossil site at Longdan

The fossil site is located at Longdan Village, Zhaojia Town, Dongxiang County, and it is the main locality of Longdan Fauna fossils. The composition of Longdan Fauna is dominated by carnivores, and small mammals are particularly rare. At this site, the animals have not been transported for a long distance after their death, which accurately reflects the real live states of the Fauna.

(5) The Maogou Section

This Section is located at Maogou, Dongyuan Township, Dongxiang Nationality Autonomous County, Linxia Hui Nationality Autonomous Prefecture. It represents the complete integrity of Cenozoic strata in Linxia Basin, which have been continuously deposited since Oligocene to present day, providing a more complete record of Cenozoic strata. The Maogou Section provides favorable conditions for accurately determining the age of strata and the analysis of environmental changes in the Linxia Basin brought about by the uplift of the Qinghai-Tibet Plateau. Among them, mammalian fossils have been excavated from the red clay in this stratum, including Hystrixgansuensis of Rodentia, Chasma porthetes.sp. of Carnivora, Hipparion sp. of Perissodactyla and Palaeotragus sp. and Sinotragus sp. of Artiodactyla.

Justification de la Valeur Universelle Exceptionnelle

Criterion (viii): The nominated property developed and exposed continuous late Cenozoic terrestrial facies deposits from Oligocene red beds to Holocene loess (about 30 million to 10 thousand years ago), which is one of the most complete continental biostratigraphic profiles of the late Cenozoic in Eurasia. It completely reflects the four processes of fauna replacement that mammals in the hinterland of Asia have experienced since the late Pleistocene with the uplift of the Qinghai-Tibet Plateau.It is one of the most complete examples of continental biostratigraphy of late Cenozoic in Eurasia.

The nominated property preserves a number of rare mammal fossils in the world, which is one of the most famous origins of Cenozoic mammal fossils in Eurasia. These fossils completely recorded the migration route and distribution changes of mammals in the late Cenozoic, as well as the climate evolution of the Qinghai-Tibet Plateau environment. It is a unique key area in Eurasia to study the evolution of mammals in the Cenozoic, establish biostratigraphic sequences in the Cenozoic, study the changes of climate and environmental background in the Asian continent in the late Cenozoic, and the uplift history of the Qinghai-Tibet Plateau.

Linxia Basin in Gansu Province, located at the intersection of Qinghai-Tibet Plateau and Loess Plateau, is a foreland basin on the northeastern edge of Qinghai-Tibet Plateau. The Linxia basin developed and exposed continuous late Cenozoic terrestrial facies deposits from Oligocene red beds to Holocene loess (about 30 million years ago), which is rich in mammalian fossils.

It is one of the most complete late Cenozoic terrestrial biostratigraphic sections in Eurasia.

Linxia Basin is one of the most significant and richest source regions of the late Cenozoic mammalian fossils in Eurasia. So far, more than 40,000 fossil specimens have been excavated from more than 100 fossil sites in this region. It is one of the regions with the richest mammalian fossils in China and even the whole Eurasia.

Linxia Basin is located in the northeastern edge of the Qinghai-Tibet Plateau. It has developed almost continuous sedimentary strata not later than 30 million years since the plateau uplift. And it is a natural laboratory for re-establishing biological evolution and environmental changes. The uplift of Qinghai-Tibet Plateau is one of the most important geological events in the Cenozoic. The evolutionary history of creatures living on and around the plateau has been greatly influenced by the periodic growth process of the Qinghai-Tibet Plateau.

Mammals are very sensitive to environmental changes. The Qinghai-Tibet Plateau uplifted rapidly in the late Cenozoic, and these numerous fossil resources in Hezheng area of Gansu are the key clues to understand the geological and historical period of its uplift.

These fossil specimens are excellent materials to re-establish the detailed process of evolution and extinction of ancient mammals. It is the key evidence to understand the stratigraphic age, paleoclimate, paleogeography, paleoenvironment development and paleontological variation and evolution of the northeastern margin of the Qinghai-Tibet Plateau in the late Cenozoic.

Linxia basin with its unique geographical environment is a well-deserved “Fossil Kingdom” and “Eden of Ancient Animal”. Hezheng is a region rich in mammalian fossils. The vertebrate fossils found here include more than 250 genera and species of reptiles, birds and mammals. Among them, there are more than 80 new genera and species.

The evolution history of the late Cenozoic animals from 30 million years ago to more than 1 million years ago was recorded by the fossils in this area. It was divided into four periods and named as four major fauna. They are the late Oligocene Indricotheriinae fauna, the middle Miocene Platybelodon fauna, the late Miocene Hipparion fauna and the early Pleistocene Equus fauna, respectively.

The migration route and distribution change of mammals in the late Cenozoic is recorded by mammalian fossils in Hezheng.

A large number of Indricotheriinae fossils were found on the northern side of the Qinghai-Tibet Plateau, which spanned more than 20 million years to 30 million years ago. The earliest Indricotheriinae fossils were only found in Pakistan on the southern side of the plateau. With the discovery of Indricotheriinae fossils in Mongolia, China and Kazakstan, the pathway of Indricotheriinae crossing the Qinghai-Tibet Plateau has become an important scientific issue. The phylogeny tree and migration route map of Indricotheriinae were established by analyzing the phylogenetic relationship of Indricotheriinae around the area. It is found that Indricotheriinae spread from the Mongolian Plateau on the north side of Qinghai-Tibet Plateau to South Asia in the early Oligocene, and the descendants of Pakistani Indricotheriinae returned to Gansu and Xinjiang in the late Oligocene.

During the era of Indricotheriinae, the altitude of Qinghai-Tibet area was less than 2000 meters, and animals could migrate northwards or southwords without restriction. In the era of Platybelodon fauna, there was no evidence of the occurrence of Platybelodon on the south side of Qinghai-Tibet Plateau. 15 million years ago, the Qinghai-Tibet Plateau had hindered the dispersion and migration of the Platybelodon to the south. This indicates that the Qinghai-Tibet Plateau had been gradually uplifting.

Coelodonta sp. fossil was found in Dongxiang County, which has been 2.5 million years ago. Its ancestor lived 3.7 million years ago in Ali of Tibet, where Coelodonta sp. emerged. Coelodonta sp. fossils have also been found in Hebei, Lake Baikal and other places. They migrated to the north because the climate change influenced their distribution. It was a global warm period 3.7 million years ago. Except for the Qinghai-Tibet Plateau, other areas were dominated by hot climate, and animals with long fur could only survive in alpine regions. 2.5 million years ago, with the beginning of the Ice Age, Hezheng area became cold, while more places were suitable for species like Coelodonta sp..

The environment evolution of the Qinghai-Tibet Plateau was recorded by mammalian fossil group in Hezheng.

The four different faunas refer to four different climatic conditions. It reveals that with the gradual uplift of the Qinghai-Tibet Plateau, the local climate environment has changed from warm and humid to dry and cold in northwest China.

The Indricuriinae fauna occurred about 30 million years ago, and the typical representative Indricuriinae is the largest terrestrial mammal in geological history. The Platybelodon fauna occurred 15 million years ago. At that time, the whole world was in a warm period, and the northern part of China was densely forested, including Hezheng area. In addition to the typical animal Platybelodon, there was even anthropoid.

11.6 million years ago, the earth's climate changed dramatically. At that time, forests disappeared, while grasslands appeared, and animals living on forests went extinct. Then the Hipparion fauna which adapted to grassland appeared. Until 3.6 million years ago, Hipparion fauna always dominated the Hezheng area and it was also the one with the most abundant fossils in this area.

The Ice Age started 2.5 million years ago, and the climate became very cold. With the uplift of the Qinghai-Tibet Plateau, the altitude in Hezheng area reached up to more than 2,000 meters, and there were many carnivores in this period. 2 species of Machairodus sp., 3 species of Chasmaporthetes sp., Acinonyx sp., Panthera tigris palaeosinensis and other animal fossils have been found.

The Cenozoic strata of the nominated property are not only well exposed, continuously developed and un-disturbed by geological movement, but also rich in a large number of complete and excellent fossils, which include many rare mammalian fossil groups in the world, and by which a stratigraphic time framework based on mammalian fossil assemblages has initially been established. These facts enable the nominated property to be a unique typical area in Eurasia for studying the stratigraphic division and correlation, the paleontological evolution and biodiversity in this period. The nominated property is also a key area for studying the evolution of Cenozoic mammals, establishing Cenozoic biostratigraphic sequences, studying the changes of climatic and environmental background in the Asian continent in the late Cenozoic and the uplift history of the Qinghai-Tibet Plateau. Cenozoic is a period of rapid uplift of the Qinghai-Tibet Plateau, and the four main mammalian Faunas excavated in Hezheng area represent the remarkable changes in the evolution and diversity of mammalian groups under the background of the uplift of the Qinghai-Tibet Plateau, the rapid change in paleoenvironment and paleoclimate, and are typical examples of the response of mammalian evolution responding to the uplift of the Plateau.

Hezheng area is one of the most significant source regions of the Cenozoic mammalian fossils in Eurasia. The top 10 recognised world records of Cenozoic fossils in Linxia are: 1) The largest gathering place of Paraceratherium (the largest terrestrial mammals ever existed) in the world, and the world's earliest Quaternary Coelodonta sp. fossil, 2) the world's richest Platybelodon fossil, 3) the world's largest Hipparion Fauna, 4) the world's earliest known savanna community, and 5) the largest hyena -- Dinocrocuta gigantea, 6) the world's unique Hezhengia bohlini, 7) the closest known ancestor of bears in the world -- Ursavus tedfordi, 8) the earliest known onomatopoeic bird in the world -- Panraogallus hezhengensis, 9) the longest known preserved protein in the world, and 10) the world’s largest Equus fossil -- Equus eisenmannae.

The Indricotheriinae Fauna in the nominated property is composed of a series of peculiar creatures, among which rhinocerotidae species are absolutely dominant. The most representative fossil species is Paraceratherium sp. which is the largest terrestrial mammal in geological history. The predatory animals in this Fauna are still quite primitive, and only a few Creodonta, represented by Megalopterodon sp. exist. Members of the Fauna also include a fossil Rodentia species Tsaganomys altaicus, Schizotherium ordosium of Perissodactyla and Paraentelodon macrognathus of Artiodactyla.

The Platybelodon fossils in the nominated property rank first in China and is rare in the world. China is the country with the richest Platybelodon fossils, while Hezheng area is one of the famous fossil sites of Platybelodon in China. There are about 60 relatively complete skulls and mandibles of the Platybelodon excavated from Hezheng area, which exceeds the amount excavated from any fossil site of the Platybelodon Fauna in the world. In the comparison of horizontal geographical scope, Platybelodon were found in many places along the north side of the Qinghai-Tibet Plateau, but no trace of such animals was found in the Indo-Pakistan subcontinent on the south side of the Qinghai-Tibet Plateau at the same period. This reflects that the Qinghai-Tibet Plateau had been uplifted to a height which was enough to hinder species exchange in the Middle Miocene. On a larger scale, the Platybelodon Fauna in Hezheng area also recorded the spread of An-chitherium sp. between North America and Eurasia. The event happened in a cold period about 20 million years ago. Because of sea level decline, the Bering Strait turned to a land bridge, which enabled An-chitherium sp. to reach Asia from North America and finally migrate to Europe.

The Hipparion Fauna in the nominated property, which represents the transformation of mammals from ancient to modern species, is also a Fauna rich in species and specimens. 12 million years ago, the earliest Hipparion crossed the Beringia land bridge and spread from North America to Asia, and then quickly spread to Europe and northern Africa. The following highly adaptive radiation was an important evolution event in Eurasian Fauna. Hipparion dongxiangense, discovered in the nominated property, is the earliest known Hipparion in Eurasia. Hyenas are typical representatives of top Carnivore in the Hipparion Fauna. The nominated property preserved the world's largest known hyena fossil -- Dinocrocuta gigantea. The Dinocrocuta gigantea is the largest hyena in the world. Most Dinocrocuta gigantea weigh about 210-240 kilograms, and the largest fossil of Dinocrocuta gigantea's skull has been found in Hezheng area. According to calculations, this individual might weigh up to 380 kilograms.

The nominated property preserved the world's largest Equus fossil -- Equus eisenmannae. It is a new Equus fossil species found in the loess stratum of early Pleistocene in Linxia basin 2.5 million years ago. It is the largest Equus in the world, with a skull length of 0.73 meters and the longest horse face in the world. This horse also has the largest head-to-body ratio among all horses. So far, Equus eisenmannae is only found in Hezheng area. The nominated property also preserves the world's earliest Quaternary.

Coelodonta fossils. Coelodonta is among the most famous ice-age animals and also one of the most successful species in the ice age. Coelodonta originated from the Qinghai-Tibet Plateau at high altitude, and then moved out of the Qinghai-Tibet Plateau to Siberia at high latitude in the north. A complete skull and mandible of Coelodonta nihowanensis were found in the nominated property, with a geological age of 2.5 million years. This is the earliest known Quaternary Coelodonta fossil in the world, which is of great significance for understanding the early evolution of Coelodonta.

The late Cenozoic fossil Fauna sequence of the nominated property records many important biological evolution and migration events of East Asian mammal Fauna during the uplift of the Qinghai-Tibet Plateau and the related environmental changes. The Indricotheriinae Fauna living in the woodland environment had gone extinct in the late Oligocene (23 million years ago), and then Proboscidea achieved great development in diversity and abundancy, and in the middle Miocene, a Platybelodon Fauna adapted to the forest environment emerged. However, the severe drought events that began 11.6 million years ago drove the replacement of the Platybelodon Fauna by the Hipparion Fauna migrating from North America, which gained absolute superiority in the open grassland environment, and lasted until the end of Pliocene. With the advent of the Quaternary Ice Age (2.5 million years ago), a new wave of migration, represented by Equus and accompanied by diverse carnivores, spread from North America again, and quickly replaced the Hipparion and its symbiotic species, forming the foundation of modern Fauna.

Nominated property is an important evolution and dispersal center of mammals in Eurasia during Cenozoic era, especially for Bovidae and Rhinocerotidae. Rhinocerotidae fossils are an important part of the late Cenozoic mammalian Fauna in Linxia Basin. The nominated property preserves one of the most complete fossil records of the evolutionary sequence of the Cenozoic Rhinocerotidae in the world. Different from the late Miocene Hipparion dominated Fauna in North America and Europe, the Rhinocerotidae was the most abundant taxonomic group in Linxia Basin during this period. Among them, the late Oligocene Indricotheriinae and the late Miocene Chilotherium are the dominant species in the Fauna of these two eras, respectively. The discovery of Iranotherum morgan and Diceros gansuensis in the nominated property proves that Iranotherium sp. and Diceros bicornis originated in China, and then migrated to Iran, Africa and other places. Iranotherium sp. became extinct about 7 million years ago, while Diceros bicornis has evolved and survived in Africa to this day.

The nominated property not only preserves the typical examples of the evolution of mammals in Cenozoic in Eurasia, especially Carnivores, Proboscis, Perissodactyla and Artiodactyla, but also is a favorable area to reveal the biological evolution and its relationship with the changes of Cenozoic climate and environment. At the same time, the nominated property is also a typical area where the Cenozoic biostratigraphy is divided and compared by using mammalian fossils, and there is a classic section. For example, the late Miocene mammal Fauna in Linxia Basin can be divided into four strata, and each stratum has different mammalian fossils as a symbol of division and comparison, which proves that mammalian fossils are of great significance in biostratigraphy.

The four fossil sites of the Indricotheriinae Fauna Fossil site at Yagou-Tala, the Platybelodon Fauna Fossil site at Laogou, the Hipparion Fauna Fossil site at Hualin and the Equus Fauna Fossil site at Longdan are of world-class scientific values. The geological relic site of Maogou Section are the most typical and complete stratigraphic records of the basin evolution in Linxia basin, which have preserved precious records of geological environment changes over time for mammalian fossils in the Cenozoic and also have world-class scientific values. All the above-mentioned world-representative ancient species have well-preserved excavated fossils preserved in Hezheng County Paleontological Fossil Museum and Linxia Geopark Museum. These continuous sections, which are rich in mammalian fossils, are rare evidence reflecting the uplifting history of the Qinghai-Tibet Plateau, and their potential values is no less than that of the world-famous Siwalik on the south slope of Himalaya. These fossils were formed in the Cenozoic era, the key period of the uplift of the Qinghai-Tibet Plateau, reflecting the relationship between the evolution and migration of Cenozoic mammals and the uplift of the Qinghai-Tibet Plateau, and filling the knowledge gap in the global paleontology community. Many specimens can not only deserve fine heritages in China, but also be rare typical fossils in the Globe. There are many important type specimens, which are of great academic significance and conservation values.

Déclarations d’authenticité et/ou d’intégrité

The Cenozoic terrestrial strata of the nominated property are continuously developed and well exposed, ranging from Oligocene to Quaternary, and the sediments are relatively stable and the strata are nearly horizontal. The mammalian fossils are from the continuous deposition from red beds of the late Oligocene to the loess of the Holocene, with continuous fossil group sequences and abundant fossils, as well as complete phylogenic sequences and full spectra of population composition for certain taxonomic groups. The fossils reveal rich species, high biodiversity and complete ecological structure across different geological periods.

There are 228 species (including undetermined species) belonging to 136 genera of 8 orders, 48 families in the known Cenozoic fossil records in Linxia Basin, dating from late Oligocene to early Pleistocene, which can reflect the changes in mammal diversity across different periods of Cenozoic. From the perspective of time evolution, there are significant changes in species composition and diversity of mammalian fossils, which can be divided into different stages. Among them, in the middle Miocene, late Miocene and early Pleistocene, the biodiversity in mammals was the highest, while in the late Oligocene to early Miocene, the diversity was the lowest, and the diversity in Pliocene was at a medium level. From the composition of mammalian fossils, these fossil materials include a large number of skulls, but also complete skeletons, and the number of limb bones is even more abundant. Among them, the late Miocene Hipparion Fauna has the highest species diversity and individual abundancy, including mammal fossils in at least four stratigraphic layers of fossils and many sites.

The nominated property is not only rich in herbivorous mammal fossils, but also rich in carnivorous animal fossils, reflecting a complete ecosystem structure. Carnivora fossils in Linxia Basin have been excavated from dozens of fossil sites, which can be identified as 10 Fauna, namely, the Shinanu Fauna at the turn of Cenozoic and Miocene, the Laogou Fauna in the middle Miocene, the Yatang Fauna in the late Miocene, the Guonigou Fauna in the early of late Miocene, the Dashenggou Fauna in the middle of late Miocene, the Yangjiashan Fauna in the middle and late Miocene, the Qingbushan Fauna in the late of late Miocene, the Shili Fauna at the turn of Miocene and Pliocene, the Zuitou Fauna in the late Pliocene and the Longdan Fauna in early the Pleistocene.

The principle on the delineation of the boundary of the nominated property and its buffer zone of Hezheng Mammalian Fossil Sites of Gansu includes:
1) an area containing all the elements needed to express its outstanding universal values;
2) The area is of the nature of protected areas, and is consistent with or included in the existing protected areas;
3) Avoid the areas where human activities adversely affect the heritage value to the maximum extent, so as to maintain the naturalness of the nominated property;
4) The buffer zone is located around the nominated property to provide buffer and additional protection for conservation and management.

Each nominated property is the outcrop of the stratum where the fossils of typical mammal groups are located. Among the nominated properties, the Platybelodon Fauna fossil site at Laogou and the Hipparion Fauna fossil site at Hualin are located in the first-class protected area of Hezheng Paleontology National Geopark in Gansu. The Indricotheriinae Fauna fossil sites at Yagou-Tala and the Equus Fauna fossil site at Longdan belong to the first-class protected sites. Maogou Section is the second-class protected site of Linxia World Geopark.

For each typical mammal fossil group, the scope of the nominated property is defined based on the outcrop of its local stratum, and the buffer zone around the nominated property is defined based on the easily recognizable geomorphological features such as ridges, valleys, and roads. In this way, the requirements of the protection of the potential OUVs of the nominated property and its management can be met.

All the nominated properties are first-class protected sites, second-class protected sites or first-class protected areas of geological parks, which are managed according to the master plan of the national geopark and the relevant requirements of the Measures for the Administration of National Natural Parks.
The nominated property of Hezheng Mammalian Fossil Sites of Gansu contains the typical mammalian fossil sites and geological section that can reflect the OUVs, which is complete in terms of attribute, scope and value, and meets the requirements of integrity, protection and management by the Operational Guidelines for the implementation of the World Heritage Convention.

Comparaison avec d’autres biens similaires

The nominated property perfectly preserves the most representative large mammal fossils known of Eurasia from the late Oligocene to the early Pleistocene, and can fill in the gap in the World Heritage List for Eurasian mammalian fossil records in the Cenozoic period, especially for the life evolution and major migration events of large mammals in the hinterland of the Asian continent during the Cenozoic.

By July 2019, there are 17 fossil heritage sites in the World Heritage List. Fossil world heritage includes three categories: Paleozoic marine invertebrate and terrestrial organism fossils, Mesozoic dinosaurs and other vertebrate fossils, and Cenozoic mammal and plant fossils. They are: (1) Early Cambrian marine community fossils, Devonian "fish age" fossils and Carboniferous terrestrial organism fossil sites; (2) The fossil evidence of the Permian and Triassic mass extinctions, the Triassic mammalian ancestors, ancient plant fossils and dinosaur fossil sites, and the special evidence that the Heksulubo meteorite hit the earth at the end of the pre-Cretaceous; (3) The extinct Paleocetacea fossils of the Neogene in Eocene, the only evidence of early evolution of mammals, the plant fossil in volcanic ash and marl, and the vertebrate fossil sites from Pleistocene to Pliocene. At present, the mammal fossils excavated from the nominated properties are obviously different from the mammal fossils of the Cenozoic in other world heritage sites. The latter are found in Australia, Germany, Egypt, Kenya and other places. The nominated property perfectly preserves the most representative large mammalian fossil group in Eurasia from the late Oligocene to the early Pleistocene, which can fill in the gap in fossil records and the geological timescale represented by fossil world heritage sites.

The types, geological ages and geographical distribution of late Cenozoic mammalian fossils excavated from the nominated property are obviously different from the above-mentioned existing fossil world heritage sites. Even compared with the existing world heritage sites of Cenozoic mammalian fossils, the species of mammalian fossils from the nominated property are obviously different. They are found in Australia (large marsupials), Germany (mammals), Egypt (whales), Kenya (human skulls, mammals, turtles, crocodiles, etc.) and other places. The mammalian fossils of the nominated property belong to the Oligocene-Miocene period in the Asian continent, which can fill in the gaps in the dimension of the geological era and the Asian continent.

At the same time, the World Heritage List has not yet included a typical fossil example reflecting the response and evolution of the Cenozoic large mammal community and its corresponding ecosystem in the hinterland of Eurasia to the uplift of the Qinghai-Tibet Plateau. The influence derived from the evolution and migration events of large mammals recorded in the nominated property have continued to this day. Some species, such as Diceros bicornis, which originated from the nominated property, are still among one of the most striking rare large animals in the modern world. In addition, the early Pleistocene Equus Fauna in Hezheng is different from most of the known early Pleistocene mammal Faunas, and it is also very different from the modern mammal Fauna, but it is highly similar to the modern mammal Fauna in Mount Everest area in taxonomic units and diversity. There are 12 families and 8 genera of early Pleistocene mammals in Hezheng area, which can still be seen in the modern Everest area, which is consistent with the ecological characteristics reflected by different species in the Fauna. It is also a rare example in the world that paleontological fossils of the Cenozoic and the uplift of the Qinghai-Tibet Plateau have such a long-lasting and complete coupling relationship.

Linxia basin is located in the northeastern edge of the Qinghai-Tibet Plateau, where sedimentary strata of the Cenozoic with a thickness of more than 1600 meters are accumulated. This is unique in the surrounding areas of the Qinghai-Tibet Plateau. For example, a similar basin topography in Pakistan also received a large number of sedimentary strata of the Cenozoic . However, compared with the sandstone and clay in Linxia Basin, most of them are gravel and the geological structure is active. And most of the animal bones are smashed, and few remain intact. Moreover, the paleontological fossils of Cenozoic are isolated, so it is difficult to make regional geological comparison.

Among the four ancient Faunas represented by the nominated property, namely the late Oligocene Indricotheriinae Fauna, the middle Miocene Platybelodon Fauna, the late Miocene Hipparion Fauna and the early Pleistocene Equus Fauna, the fossil specimens of the Hipparion Fauna are the most abundant (Deng, 2004), and its fossil reserves and the number of collected fossil skulls are the highest across Eurasia. It surpassed Pikemi and Samos, the world's famous Hipparion Fauna fossil sites in Greece. At the same time, the nominated property retains the world's richest fossils of the Hipparion Fauna. The Hipparion Fauna fossils here include the most abundant species, including Promephitis sp., Machairodus sp., Metailurus sp., Chasmaporthetes sp., Hipparion sp., Chilotherium sp., Aceratherium sp., Parelasmotherium sp., Chleuastochoerus sp., Palaetraggus sp., and Gazella sp. More than 6,000 skull specimens of the Hipparion Fauna have been excavated from the nominated property, and there are many complete limb bones, too. In quantity and quality, it not only surpasses the fossil sites of Shanxi and Shaanxi, but also surpasses the two famous fossil sites in Greece of Europe. The fossil specimen collection of the Platybelodon Fauna from the nominated property is the most abundant not only in China but also in Eurasia, and its quantity exceeds the collections of American Museum of Natural History and Beijing Museum of Natural History. Kubanochoeros gigas fossils are also one of the best specimens in the world.

The nominated property is located in the northeast edge of the Qinghai-Tibet Plateau in the hinterland of the Asian continent. It connects Mongolia-Siberia, Qinghai-Tibet Plateau, and South Asia from north to south. It also connects Central Asia, the Middle East, and the Far East from east to west. It is at the key crossroads of the migration route of mammals in the Asian continent of the Cenozoic. It is a rare evidence reflecting the uplifting history of the Qinghai-Tibet Plateau and the evolution history of mammals, which can fill the gaps in the global fossil world heritage list and the tentative list of world heritage.
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