Evolution of the taxonomic diversity of Mongolian Ordovician-Silurian corals

Changes in the taxonomic diversity of Mongolian Ordovician-Silurian corals (Tabulatoidea, Heliolitoidea, Cyrtophyllida, Rugosa) are analyzed. Evolution of the taxonomic diversity is analyzed in two aspects: quantitative and qualitative changes. Changes in the diversity of Mongolian corals are caused by (1) evolutional developmental stage of the group and its adaptational possibilities (internal reason) and (2) changes in the environmental parameters, which reproduce regional and general global events (external reason).     

New species of <Emphasis Type="Italic">Jakutoproductus</Emphasis> from the Lower Permian of Verkhoyansk Region

Two new brachiopod species of Jakutoproductus, J. lenensis sp. nov. and J. talchanensis sp. nov., are described. J. lenensis occurs in the upper part of the J. verkhoyanicus Zone of the Khorokytian Horizon (Asselian–Sakmarian deposits) of the lower reaches of the Lena River and in the Sobolokh-Mayan and Allara-Khadaryn’ya river basins. J. talchanensis is identified from the Khorokytian Horizon of the Talchan River (Baraiy River basin). A new subzone, the J. lenensis Subzone, is proposed for the upper part of the J. verkhoyanicus Zone of the Khorokytian Horizon of the Verkhoyansk Region.     

Biostratigraphy and important biotic events in the Western Verkhoyansk Region around the Sakmarian–Artinskian boundary

A diverse marine invertebrate fauna was found in the Echij Formation (Sakmarian–Artinskian) at the Arkachan, Chelge, and Nizhnyaya Dielendzha sections, all Western Verkhoyansk Region, North-East of Russia. The biostratigraphic sequence of ammonoid, brachiopod, bivalve, and foraminiferal assemblages in the Echij Formation of the Western Verkhoyansk Region is studied. Five ammonoids units are identified in the Echian Regional Stage (“Horizon”): Uraloceras subsimense, Uraloceras omolonense, Neoshumardites triceps hyperboreus, Eotumaroceras endybalense, and Eotumaroceras subyakutorum beds. The first two divisions contain ammonoids of the Arkachanian association, and the last three contain the Endybalian association. The boundary between the Sakmarian and Artinskian stages is established at the base of Neoshumardites triceps hyperboreus beds. In the Sakmarian interval of the Echij Regional Stage of the Verkhoyansk Region, a brachiopod biostratigraphic sequence similar to that of the Kolyma–Omolon Region is observed: Jakutoproductus insignis, Jakutoproductus terechovi, and Jakutoproductus rugosus zones. In the lower part of the Artinskian stage, Uraloproductus stuckenbergianus beds are identified, which are characterized by a rich brachiopod assemblage (Peregoedov et al., 2009), not typical for Verkhoyansk Region. The bivalves, identified in the Lower Echij Subformation, presumably belong to the Merismopteria permiana, Cypricardinia eopermica, and Cypricardinia borealica zones of the Ogonerian Horizon of the Kolyma–Omolon Region. Bivalves of the Middle and Upper subformations are characteristic of the Edmondia gigantea and Aphanaia lima zones of the Koargychanian Regional Stage (“Horizon”). The foraminifera complex identified in the Echij Formation is compared with the complex of the lower part of the Sandy Foraminifera horizon of the northeast of the Siberian platform, to which the Tustakh Formation belongs. The beginning of the wide distribution of the Early Permian foraminifera in the Western Verkhoyansk Region was recorded at the base of the Artinskian. The Sakmarian–Artinskian boundary interval in the Verkhoyansk Region is characterized by three significant biotic events: the replacement of the brachiopod Jakutoproductus by Inoceramus-like bivalves, the first appearance of the Endybalian ammonoid association, and biotic invasions from the Uralian and North American regions. An important factor of the Late Sakmarian–Early Artinskian events was a large sea level rise (the Echian transgression), which significantly changed the environmental conditions for East Siberian marine invertebrates, and contributed to the spread of new faunas.     

Large Spatial Scale Variability in Bathyal Macrobenthos Abundance,Biomass, α- and β-Diversity along the Mediterranean Continental Margin

The large-scale deep-sea biodiversity distribution of the benthic fauna was explored in the Mediterranean Sea, which can be seen as a miniature model of the oceans of the world. Within the framework of the BIOFUN project (“Biodiversity and Ecosystem Functioning in Contrasting Southern European Deep-sea Environments: from viruses to megafauna”), we investigated the large spatial scale variability (over >1,000 km) of the bathyal macrofauna communities that inhabit the Mediterranean basin, and their relationships with the environmental variables. The macrofauna abundance, biomass, community structure and functional diversity were analysed and the α-diversity and β-diversity were estimated across six selected slope areas at different longitudes and along three main depths. The macrobenthic standing stock and α-diversity were lower in the deep-sea sediments of the eastern Mediterranean basin, compared to the western and central basins. The macrofaunal standing stock and diversity decreased significantly from the upper bathyal to the lower bathyal slope stations. The major changes in the community composition of the higher taxa and in the trophic (functional) structure occurred at different longitudes, rather than at increasing water depth. For the β-diversity, very high dissimilarities emerged at all levels: (i) between basins; (ii) between slopes within the same basin; and (iii) between stations at different depths; this therefore demonstrates the high macrofaunal diversity of the Mediterranean basins at large spatial scales. Overall, the food sources (i.e., quantity and quality) that characterised the west, central and eastern Mediterranean basins, as well as sediment grain size, appear to influence the macrobenthic standing stock and the biodiversity along the different slope areas.     

Brachiopods, biostratigraphy, and correlation of the Permian marine deposits of Mongolia

Six horizons and 11 brachiopod zones are distinguished in the Permian of the Khangai-Khentei (Boreal) and South Mongolian (Tethys) marine basins of Mongolia on the base of monographic study of brachiopods and literary data on other faunal groups. The distinguished in the Permian basins of Mongolia biostratons are correlated with zonal brachiopod scales of neighboring regions of Northeast Asia. Possible bio-geographical relations of the Mongolian Permian marine basins and channels of brachiopods are analyzed. Forty-five brachiopod species are figured including species, which were first described from Mongolia, zonal index species and typical representatives of zonal assemblage.     

Two millennia of changes in human ecology: archaeobotanical and invertebrate records from the lower Ica valley, south coast Peru

This paper presents archaeobotanical and invertebrate evidence from the flotation and analyses of 46 archaeological contexts from six middens from the Samaca and Ullujaya basins, lower Ica Valley, south coast of Peru. This is part of one of the world’s driest deserts and organic remains can enjoy extraordinary preservation in its hyperarid climate. Each of these contexts represents snapshots with which to piece together a picture of changing human ecology in the lower Ica Valley over nearly two millennia, from Ocucaje Phases 3/4 of the Early Horizon (c. 750 b.c.); through to Early Nasca Phases 2/3 (c. a.d. 100–450); Late Nasca Phases 6/7 (c. a.d. 450–600) and Middle Horizon Epoch 2 (c. a.d. 900). They also offer proxy evidence of wider ecological changes in these basins. Read together with geoarchaeological and pollen data, the archaeobotanical data we present show a gradual intensification of agriculture from small-scale Early Ocucaje societies subsisting mainly on gathered marine and terrestrial resources, through to sophisticated irrigation agriculture by Nasca times, but culminating in a collapse of agricultural production and a return to the gathering of wild marine and plant resources much later, during the Middle Horizon. This trajectory of human ecology is consistent with the model presented elsewhere of a gradual removal of Prosopis dominated riparian woodland for the purpose of increasing agricultural production, which in time exposed the landscape of the lower Ica Valley to high-energy, episodic flood events and of one of the world’s strongest and most persistent wind regimes.     

Upper Ordovician sequences of western Estonia

The Upper Ordovician (uppermost Caradoc-Ashgill) section of western Estonia consists of a series of seven open-shelf carbonate sequences. Depositional facies grade laterally through a series of shelf-to-basin facies belts: grain-supported facies (shallow shelf), mixed facies (middle shelf), mud-supported facies (deep shelf and slope) and black shale facies (basin). Locally, a stromatactis mud mound occurs in a middle-to-deep shelf position. Shallow-to-deep shelf facies occur widely across the Estonian Shelf and grade laterally through a transitional (slope) belt into the basinal deposits of the Livonian Basin.

Each sequence consists of a shallowing-upward, prograding facies succession. Sequences 1 (Upper Nabala Stage) and 2 (Vormsi Stage) record step-wise drowning of underlying shelf units (lower Nabala) that culminated in the deposition of the most basinal facies (Fjäcka Shale) in the Livonian Basin. Sequences 3–6 comprise the overlying Pirgu Stage and record the gradual expansion of shallow and middle-shelf facies across the Estonian Shelf. The Porkuni Stage (sequence 7) is bracketed by erosional surfaces and contains the shallowest-water facies of the preserved strata. The uppermost part of the section (Normalograptus persculptus biozone) is restricted to the Livonian Basin, and includes redeposited carbonate and siliciclastic grains; it is the lowstand systems tract of the lowest Silurian sequence 8. Sequence 7 and the overlying basinal redeposited material (i.e., the lowstand of sequence 8) correspond to the latest Ordovician (Hirnantian) glacial interval, and the bracketing unconformities are interpreted as the widely recognized early and late Hirnantian glacial maximums.

The sequences appear correlative to Upper Ordovician sequences in Laurentia. Graptolite biozones indicated that the Estonian sequences are equivalent to carbonate ramp sequences in the western United States (Great Basin) and mixed carbonate-siliciclastic sequences in the eastern United States (Appalachian Basin–Cincinnati Arch region). These correlations indicate a strong eustatic control over sequence development despite the contrasting tectonic settings of these basins.     

新疆准噶尔盆地周边晚石炭世的珊瑚*

新疆北部准噶尔盆地周边石炭系广泛出露, 其中上石炭统发育海相火山—沉积序列, 包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组, 东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎屑岩中获得的四射珊瑚9属17种和床板珊瑚2属3种, 对石钱滩组中的3个新种进行了详细的系统古生物学描述。上述珊瑚化石的地质时代主要为巴什基尔期至莫斯科期。在珊瑚动物群的组成上, 哈拉阿拉特组中新发现Caninophyllum属分子, 结合盆地东、西部共同产出的床板珊瑚Cystodendropora 属分子, 说明整个准噶尔盆地周边的动物群面貌大致类似, 而西准噶尔地区的化石丰度、分异度显著低于盆地东部和东南部。综合前人资料, 目前在准噶尔盆地周边发现的珊瑚化石有约一半为地方性分子。本文认为研究区珊瑚化石的分布和组成特征与晚石炭世准噶尔洋走向封闭或半封闭的演化趋势密切相关。     

新疆准噶尔盆地周边晚石炭世的珊瑚*

新疆北部准噶尔盆地周边石炭系广泛出露, 其中上石炭统发育海相火山—沉积序列, 包括西准噶尔地区的哈拉阿拉特组、阿腊德依克赛组, 东准噶尔地区的石钱滩组以及盆地南部的祁家沟组、奥尔吐组等。本文研究在上述各地层的灰岩层或夹层、碎屑岩中获得的四射珊瑚9属17种和床板珊瑚2属3种, 对石钱滩组中的3个新种进行了详细的系统古生物学描述。上述珊瑚化石的地质时代主要为巴什基尔期至莫斯科期。在珊瑚动物群的组成上, 哈拉阿拉特组中新发现Caninophyllum属分子, 结合盆地东、西部共同产出的床板珊瑚Cystodendropora 属分子, 说明整个准噶尔盆地周边的动物群面貌大致类似, 而西准噶尔地区的化石丰度、分异度显著低于盆地东部和东南部。综合前人资料, 目前在准噶尔盆地周边发现的珊瑚化石有约一半为地方性分子。本文认为研究区珊瑚化石的分布和组成特征与晚石炭世准噶尔洋走向封闭或半封闭的演化趋势密切相关。     

Species structure, contemporary distribution and status of the Siberian surgeon Acipenser baerii

A detailed analysis of the historical and contemporary range of the Siberian sturgeon, Acipenser baerii, shows that the contemporary status of its populations and forms can be described as threatened or endangered. Recently, the abundance of the nominal subspecies, A. b. baerii, which inhabits mainly the Ob River basin, decreased sharply. Due to construction of hydroelectric dams, up to 40% of the spawning grounds became inaccessible for migrating sturgeon of this subspecies. The Lake Baikal subspecies, A. baerii baicalensis, is extremely rare and was included in the Russian Federation Red Data Book in 1983. The abundance of the east Siberian subspecies, A. baerii stenorrhynchus, inhabiting the basins of the east Siberia rivers, has also significantly decreased during the last few years. Its range in the Yenisey and Lena River basins is gradually being reduced. Gametogenesis is anomalous in a high number of females from all populations of this subspecies (in the Kolyma and Indigirka river stocks 80–100% of females were anomalous in 1987–1989). These anomalies seem to be caused by high levels of water pollution.     

Phylogenetic analysis of the genus Thymallus (grayling) based on mtDNA control region and ATPase 6 genes, with inferences on control region constraints and broad-scale Eurasian phylogeography

We present first insights into the molecular phylogeny of the grayling genus Thymallus (Salmonidae) using sequences from the mitochondrial control region and ATPase6 genes. A suite of analytical approaches were applied for each gene separately and for the combined data. The ATPase6 gene is shown to have a mean divergence rate across the genus of 2.46 times faster than the complete control region. Based on the combined data, four major (internal) clades, presumably originating in the Pliocene, were resolved with high support in all analyses and represented two distinct lineages in the Amur basin, one lineage in all remaining Siberian and Mongolian drainages, and one lineage corresponding to European grayling Thymallus thymallus. The resolution of multiple lineages, from both additional internal and terminal clades, within each major drainage basin underscores the complexity and effects that Pleistocene hydrological dynamics have had on the distribution of biodiversity in Siberia.     

Late Moscovian (mid-Pennsylvanian) rugose corals from Wadi Araba (Egypt,Eastern Desert): Taxonomy,palaeoecology and palaeobiogeography

An important late Moscovian rugose coral association is described from the Rod El Hamal Formation of the Wadi Araba area (northern Eastern Desert, Egypt). The upper part of the formation yielded a moderately abundant but poorly diversified coral fauna composed of large dissepimented solitary rugose corals. In total, six species belong to the Bothrophyllidae and the Geyerophyllidae, including three new species: Bothrophyllum suezensis, Bothrophyllum cylindricum, and Amygdalophylloides omarai. Three undeterminable Bothrophyllidae taxa are left in open nomenclature. The corals were attached to the soft substrate by talons and rootlets, either rooted and growing upward as mud-stickers or as secondary recliners. They show frequent rejuvenations and constrictions. Encrustation and/or bioerosion are scarce. Carbonate microfacies indicate a habitat in littoral and inner neritic zones adjacent to a low terrigenous hinterland. Colonial taxa are missing and tabulate corals are rare. The corals from the Rod El Hamal Formation are the only example of a late Moscovian coral fauna on the southern margin of the Palaeotethys, that is to say along the northern margin of Gondwana. The association shows similarities with northwestern Spain (Cantabrian Mountains), the Donets and Moscow basins, and thus a general attribution to the Palaeotethys realm.     

Allozymes,mtDNA and microsatellites study introgression in a stocked trout population in France

A comparative study of disturbed (downstream) and undisturbed (upstream) populations in a French Mediterranean river (the Sorgue) was conducted to assess the fate of introgressing hatchery-genes in the aboriginal gene pool. Variation was assessed at 27 protein-coding loci, three microsatellite loci and two mtDNA restriction sites. The results were compared to those from another Mediterranean drainage basin (that of the river Orb). The genetic pattern observed among markers and drainage basins was found to be noticeably different. A reduction in population size is hypothesized to explain the lower variability observed in the upper part of the river Sorgue. Estimations of hatchery gene flow were different between loci but in the same range of values between markers.     

Deep-Sea Biodiversity in the Mediterranean Sea: The Known,the Unknown,and the Unknowable

Deep-sea ecosystems represent the largest biome of the global biosphere, but knowledge of their biodiversity is still scant. The Mediterranean basin has been proposed as a hot spot of terrestrial and coastal marine biodiversity but has been supposed to be impoverished of deep-sea species richness. We summarized all available information on benthic biodiversity (Prokaryotes, Foraminifera, Meiofauna, Macrofauna, and Megafauna) in different deep-sea ecosystems of the Mediterranean Sea (200 to more than 4,000 m depth), including open slopes, deep basins, canyons, cold seeps, seamounts, deep-water corals and deep-hypersaline anoxic basins and analyzed overall longitudinal and bathymetric patterns. We show that in contrast to what was expected from the sharp decrease in organic carbon fluxes and reduced faunal abundance, the deep-sea biodiversity of both the eastern and the western basins of the Mediterranean Sea is similarly high. All of the biodiversity components, except Bacteria and Archaea, displayed a decreasing pattern with increasing water depth, but to a different extent for each component. Unlike patterns observed for faunal abundance, highest negative values of the slopes of the biodiversity patterns were observed for Meiofauna, followed by Macrofauna and Megafauna. Comparison of the biodiversity associated with open slopes, deep basins, canyons, and deep-water corals showed that the deep basins were the least diverse. Rarefaction curves allowed us to estimate the expected number of species for each benthic component in different bathymetric ranges. A large fraction of exclusive species was associated with each specific habitat or ecosystem. Thus, each deep-sea ecosystem contributes significantly to overall biodiversity. From theoretical extrapolations we estimate that the overall deep-sea Mediterranean biodiversity (excluding prokaryotes) reaches approximately 2805 species of which about 66% is still undiscovered. Among the biotic components investigated (Prokaryotes excluded), most of the unknown species are within the phylum Nematoda, followed by Foraminifera, but an important fraction of macrofaunal and megafaunal species also remains unknown. Data reported here provide new insights into the patterns of biodiversity in the deep-sea Mediterranean and new clues for future investigations aimed at identifying the factors controlling and threatening deep-sea biodiversity.     

On the diversity and taxonomic status of graylings (Thymallus Thymallidae) from the Lena River

Two forms of graylings were distinguished in the Lena River, which differ in body coloration, the shape and pattern of the dorsal fin, and biological characteristics. With respect to these traits, the forms are divided between the upper and lower Lena. The first inhabits most of the basin, from the upper courses to the lower reaches, whereas the second inhabits the Lena delta and the adjacent arctic rivers and their tributaries. Comparative analysis of meristic traits revealed their low appropriateness for diagnosing Lena lineages as well as grayling populations inhabiting other northern rivers of Siberia. The body and fin coloration in the upper Lena form significantly differ from that found in forms and subspecies of graylings from the basins of the other rivers in the ranges of Eastern Siberian, Kamchatka, and Alaska. The lower Lena form should be classified with the Eastern Siberian subspecies T. arcticus pallasii and is closer to the populations of graylings from the rivers Anabar and Yana, and the rivers of the Chukot Peninsula and Alaska, and the upper courses of the Missouri. These results are supported by analysis of the mitochondrial DNA of graylings throughout the Paleoarctic. Further studies of these lineages and phylogenetic relationships between Arctic lineages are necessary for the final determination of the taxonomic status of the upper Lena form.     

Habitat selection, facilitation, and biotic settlement cues affect distribution and performance of coral recruits in French Polynesia

Habitat selection can determine the distribution and performance of individuals if the precision with which sites are chosen corresponds with exposure to risks or resources. Contrastingly, facilitation can allow persistence of individuals arriving by chance and potentially maladapted to local abiotic conditions. For marine organisms, selection of a permanent attachment site at the end of their larval stage or the presence of a facilitator can be a critical determinant of recruitment success. In coral reef ecosystems, it is well known that settling planula larvae of reef-building corals use coarse environmental cues (i.e., light) for habitat selection. Although laboratory studies suggest that larvae can also use precise biotic cues produced by crustose coralline algae (CCA) to select attachment sites, the ecological consequences of biotic cues for corals are poorly understood in situ. In a field experiment exploring the relative importance of biotic cues and variability in habitat quality to recruitment of hard corals, pocilloporid and acroporid corals recruited more frequently to one species of CCA, Titanoderma prototypum, and significantly less so to other species of CCA; these results are consistent with laboratory assays from other studies. The provision of the biotic cue accurately predicted coral recruitment rates across habitats of varying quality. At the scale of CCA, corals attached to the “preferred” CCA experienced increased survivorship while recruits attached elsewhere had lower colony growth and survivorship. For reef-building corals, the behavioral selection of habitat using chemical cues both reduces the risk of incidental mortality and indicates the presence of a facilitator.     

Geographical variation of allele frequencies at the LDH-A* locus in the arctic grayling Thymallus arcticus Pall. and in the European grayling Thymallus arcticus L

The allele frequencies of LDH-A* locus were studied in the population of Siberian grayling from the Kozhym River (Pechora basin) and in the population of European grayling from Pechora, Mezen', and Vym' rivers (Northern Dvina basin). In samples of both species (n = 134), three LDH-A phenotypes have been identified in total, which proved to be under the control of two alleles: LDH-A*100 and LDH-A*50. The alternative alleles of LDH-A* locus were identified in the populations of Siberian grayling from Kozhym River and in the population of European grayling from the same river and other Pechora tributaries, namely, LDH-A*100 and LDH-A*50 in the Siberian and the European grayling, respectively. However, in the European grayling populations from the Mezen' and Vym' rivers, both alleles occur at the frequencies of the rare LDH-A*100 allele of 0.143 and 0.222, respectively. According to the published data, the frequency of LDH-A*100 allele increases in the European grayling populations of northwestern (Finland) and southern (France) rivers, reaching 0.872 and 1.000 in Rhone and Loire, respectively, i.e., the values characteristic of the Siberian grayling populations.     

Mitochondrial DNA genetic differentiation of the muksun Coregonus muksun (Pallas) and related Siberian species of Coregonus (Coredonidae, Salmoniformes)

Restriction enzyme analysis of the mitochondrial DNA (mtDNA) fragment encoding subunit 1 of the NADH dehydrogenase complex (ND-1) amplified via polymerase chain reaction (PCR) has been used to obtain data on genetic differentiation of muksun Coregonus muksun (Pallas) populations. Population polymorphism with respect to the restriction sites of 18 endonucleases has been described. It has been demonstrated that the muksun is genetically related to the pidschian C. pidschian (Gmelin), its sympatric species in Siberian waters. Analysis of the median network of mtDNA haplotypes has shown that haplotypes of muksun from various Siberian basins form a common group with haplotypes of pidschian of the Arctic Ocean basin, some frequent haplotypes been found in both forms. This raises the question as to the validity of the muksun as a species. Differences within this group of haplotypes are much smaller than those typical of species of the genus Coregonus. The possibility of a hybrid origin of the muksun from a pidschian-like ancestor and species of the cisco-peled (C. sardinella-C. peled) complex is discussed.     

Biostratigraphical analysis of the Moscovian–Kasimovian transition at the neostratotype of Kasimovian Stage (Afanasievo section, Moscow Basin, Russia)

The Afanasievo Quarry, approximately 90 km southeast of Moscow and about 5 km southwest of Voskresensk, starts with Late Moscovian limestone of the Peski Formation, which is overlain by shallow-water carbonates of the Krevyakinian Horizon (Substage) (Suvorovo and Voskresensk formations) and the lower part of the Khamovnikian Horizon (Substage) (Ratmirovo and Neverovo formations). These rocks were formed under the strong influence of glacio-eustatic sea-level fluctuations and are separated by the palaeosol horizons and minor stratigraphic gaps. The Moscovian–Kasimovian transition interval contains fusulinids, brachiopods, bryozoans, corals, and conodonts. It was recently proposed [Villa, E., Task Group, 2005. Report of the Task Group to establish GSSPs at the Moscovian–Kasimovian and Kasimovian-Gzhelian boundaries. Newsletter on Carboniferous Stratigraphy 23, 9–10] that the appearance of the conodont Idiognathodus sagittalis Kozitskaya is one of the best markers for definition of the base of the Kasimovian on the global chronostratigraphic scale. The first appearance of this species is 2 m above the base of Neverovo Formation, and is close to the first appearance of the fusulinid Montiparus in the section. The possible ancestor of I. sagittalis occurs in the lower Suvorovo Formation, but is more abundant and more advanced in the middle to upper parts of the Voskresensk Formation. This lineage has potential for defining a GSSP at the first appearance of I. sagittalis.     

Tectonic and sedimentary evolution of basins in the northeast of Qinghai-Tibet Plateau and their implication for the northward growth of the Plateau

The northeast of the Qinghai-Tibet Plateau, from the Hoh Xil Basin to the Hexi Corridor Basin, demonstrates a basin-ridge geomorphy that is the result of the long-term uplift of the Qinghai-Tibet Plateau. The geological evolution of the Qinghai-Tibet Plateau is recorded in its associated basins. From the Cenozoic sedimentary filling pattern in the Hoh Xil, Qaidam and Jiuquan Basins, we find that the evolution of these basins is similar: they began as strike-slip basins, evolved into foreland basins, and then to intermontane basins. Foreland basins are the direct result of orogenic activity in the northeast of Qinghai-Tibet Plateau, and can be documented to have formed over the following time periods: 49-23 Ma for the Hoh Xil foreland basin, 46-2.45 Ma for the Qaidam foreland basin, and 29.5-0 Ma for the Jiuquan foreland basin. This northward migration in the timing of foreland basin development suggests that the northeastern part of Tibet grew at least in part by accretion of Cenozoic sedimentary basins to its northern margin.