Northeastern Eurasia Research Articles

Genetic analysis of a Yayoi individual from the Doigahama site provides insights into the origins of immigrants to the Japanese Archipelago.

Mainland Japanese have been recognized as having dual ancestry, originating from indigenous Jomon people and immigrants from continental East Eurasia. Although migration from the continent to the Japanese Archipelago continued from the Yayoi to the Kofun period, our understanding of these immigrants, particularly their origins, remains insufficient due to the lack of high-quality genome samples from the Yayoi period, complicating predictions about the admixture process. To address this, we sequenced the whole nuclear genome of a Yayoi individual from the Doigahama site in Yamaguchi prefecture, Japan. A comprehensive population genetic analysis of the Doigahama Yayoi individual, along with ancient and modern populations in East Asia and Northeastern Eurasia, revealed that the Doigahama Yayoi individual, similar to Kofun individuals and modern Mainland Japanese, had three distinct genetic ancestries: Jomon-related, East Asian-related, and Northeastern Siberian-related. Among non-Japanese populations, the Korean population, possessing both East Asian-related and Northeastern Siberian-related ancestries, exhibited the highest degree of genetic similarity to the Doigahama Yayoi individual. The analysis of admixture modeling for Yayoi individuals, Kofun individuals, and modern Japanese respectively supported a two-way admixture model assuming Jomon-related and Korean-related ancestries. These results suggest that between the Yayoi and Kofun periods, the majority of immigrants to the Japanese Archipelago originated primarily from the Korean Peninsula.

The onset of Paleo-Pacific subduction: Key evidence from the Kaishantun Accretionary Complex, northeastern Eurasia

Subduction of the Paleo-Pacific oceanic lithosphere has dominated the tectonic evolution of northeastern Eurasia since the Mesozoic. We document the time of subduction initiation based on the age, character, and paleogeographic record of the Jilin-Yanji Suture that separates the Jiamusi-Khanka Block (of Northeast China) from the northeastern North China Craton. The suture contains a series of accretionary complexes that provide abundant information for elucidating the evolution of the oceanic plates. Zircon U-Pb and Lu-Hf isotope, as well as zircon trace element data, from nine sedimentary rock samples from the Kaishantun Accretionary Complex in the easternmost segment of the Jilin-Yanji Suture document a volcanic arc setting in the end-Permian to Middle Triassic (255−244 Ma) involving the addition of juvenile crust. Based on our new data and previous studies, we propose that southwestern-directed subduction of the Jilin-Heilongjiang Ocean dominated the evolution of regional tectonics between 260 Ma and 230 Ma, which resulted in the formation of arc-related volcano-sedimentary rocks and the generation of accretionary complexes within the Jilin-Yanji Suture. The Paleo-Pacific Ocean started to subduct beneath northeastern Eurasia at ca. 235 Ma, which accelerated the closure of the Jilin-Heilongjiang Ocean and provided the major driving force for the final amalgamation of the northeastern North China Craton and the Jiamusi-Khanka Block.

Mesozoic intra-arc basin records the tectonic transition from the Paleo-Asian Ocean to the Paleo-Pacific Ocean in northeastern Eurasia

Abstract Since the Paleozoic, the tectonic evolution of northeastern Eurasia has been dominated by the Paleo-Asian Ocean and the Paleo-Pacific Ocean tectonic domains. However, the spatiotemporal framework and the timing of tectonic transition between these two oceanic domains remain enigmatic. To address this issue, we report petrological, geochronological, and geochemical data for eight sandstone samples deposited along the convergent margin between the Northeast China terranes and the North China craton in central Jilin Province, China. The results show that these sandstones are immature graywackes with a maximum depositional age of Early Triassic (248 ± 1 Ma), and their sediments were largely derived from coeval magmatic rocks in a juvenile continental arc. According to our new results and previous studies, we identified a sedimentary basin (most likely an intra-arc or forearc basin) intimately associated with one or more continental arcs along the northeastern edge of the North China craton, and we suggest that the southwestward subduction of the Jilin-Heilongjiang Ocean in the early Mesozoic accounts for this continental arc setting. There is a distinct temporal gap between the closure of the Paleo-Asian Ocean (ca. 260 Ma) and the onset of Paleo-Pacific plate subduction (234–220 Ma), which is essentially coeval with the southwestward subduction of the Jilin-Heilongjiang Ocean between 256 Ma and 239 Ma, meaning the latter is a key link that marks the transition between these two tectonic domains.

Variable plate kinematics promotes changes in back-arc deformation regime along the north-eastern Eurasia plate boundary

The stretching of the lithosphere leading to back-arc basins formation generally develops behind arc-trench systems and is considered the consequence of slab retreat relative to the upper plate. Here, we examine the deformation regime evolution within the overriding plate due to subduction processes, using thermo-mechanical numerical simulations. We explore the north-eastern Eurasia plate boundary and the mechanisms of subducting Pacific plate since 57 Ma. During this time interval, several extensional basins formed along the Eurasia margin, such as the East China Sea, the Japan Sea, and the Kuril basin. Here, we increased the simulation complexity, with the inclusion of (i) the kinematic variability of the Pacific plate over the geological past with respect to a fixed Eurasia, incorporating time-dependent (i.e., temporally evolving) velocities computed from plate motion reconstructions; (ii) a Low-Velocity Zone within the asthenosphere, and (iii) a horizontal eastward mantle flow. Our results show a crucial role of the mantle flow for the development of lithospheric extension and back-arc basin opening, and a main kinematic control of the subduction trench position, which advances and retreats, into distance intervals in the order of ∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim$$\\end{document} 100 km, and providing stages of compression and extension in a back-arc basin.

Ancient Mitogenomes Reveal the Maternal Genetic History of East Asian Dogs.

Recent studies have suggested that dogs were domesticated during the Last Glacial Maximum (LGM) in Siberia, which contrasts with previous proposed domestication centers (e.g. Europe, the Middle East, and East Asia). Ancient DNA provides a powerful resource for the study of mammalian evolution and has been widely used to understand the genetic history of domestic animals. To understand the maternal genetic history of East Asian dogs, we have made a complete mitogenome dataset of 120 East Asian canids from 38 archaeological sites, including 102 newly sequenced from 12.9 to 1 ka BP (1,000 years before present). The majority (112/119, 94.12%) belonged to haplogroup A, and half of these (55/112, 49.11%) belonged to sub-haplogroup A1b. Most existing mitochondrial haplogroups were present in ancient East Asian dogs. However, mitochondrial lineages in ancient northern dogs (northeastern Eurasia and northern East Asia) were deeper and older than those in southern East Asian dogs. Results suggests that East Asian dogs originated from northeastern Eurasian populations after the LGM, dispersing in two possible directions after domestication. Western Eurasian (Europe and the Middle East) dog maternal ancestries genetically influenced East Asian dogs from approximately 4 ka BP, dramatically increasing after 3 ka BP, and afterwards largely replaced most primary maternal lineages in northern East Asia. Additionally, at least three major mitogenome sub-haplogroups of haplogroup A (A1a, A1b, and A3) reveal at least two major dispersal waves onto the Qinghai-Tibet Plateau in ancient times, indicating eastern (A1b and A3) and western (A1a) Eurasian origins.

New Sinoalidae (Hemiptera, Cercopoidea) in Cenomanian Kachin amber, with notes on its paleobiogeographic implications

The froghopper extinct family Sinoalidae shows high paleo-diversity in mid-Cretaceous Kachin amber biota. The sinoalid genus Cretadorus Chen, 2020 is revised in this study. Araeoanasillus Poinar et Brown, 2023, tentatively placed in Sinoalidae with subfamily and tribe incertae sedis in original paper, is proposed herein to be synonymized under Cretadorus, leading to Cretadorus leptosomus (Poinar et Brown, 2023) comb. nov. A new species of this genus, Cretadorus qingyui sp. nov., is described and illustrated on the basis of an almost complete fossil trapped in Kachin amber. The Gondwanan origin of Burma Terrane suggests that Sinoalids in Kachin amber are likely one of residual groups of Gondwanan biotae, and so this family had wide paleobiogeographic distribution on the earth in the Jurassic. In the Early Cretaceous, the distribution range of Sinoalidae has reduced: it at least probably disappeared in northeastern Eurasia. This hemipteran lineage was extinct in the late Mesozoic owing to food crisis after the angiosperm floristic revolution.

An unexpected record of Moina Baird, 1850 (Crustacea: Cladocera) in Pleistocene deposits of North-Eastern Eurasia

An unexpected record of Moina Baird, 1850 (Crustacea: Cladocera) in Pleistocene deposits of North-Eastern Eurasia

Depth to the bottom of lithospheric magnetic sources beneath north-eastern Eurasia: lithospheric thermal regime and relation to seismicity

For north-eastern Eurasia (60—70° N, 90—180° E), the bottom depth of the lithospheric magnetoactive layer is estimated using the centroid method based on two-dimensional spectral analysis of the lithospheric magnetic field. The lithospheric magnetic field within the study region is described by the EMAG2v3 global model. The obtained results show that maximum values ( 50 km) of the depth to the bottom of lithospheric magnetic sources are observed almost everywhere under the Siberian platform north of 65° N. Minimum depth values (30 km) are traced under the Koryak-Kamchatka fold belt and the Okhotsk-Chukotka volcanogenic belt. Under the Verkhoyansk-Kolyma fold belt, different maximums (up to 40 km) and minimums (up to 30 km) of the bottom depth are seen. Assuming that magnetite is a main magnetic mineral in the continental lithosphere, our distribution of the bottom depth evidences for the eastward lithospheric heating — from the Siberian platform to the Koryak-Kamchatka fold belt. The revealed tendency is confirmed by independent geophysical data. Comparison of the obtained results with a distribution of epicenters of regional earthquakes (M ≥ 4.0, 1962—2020) shows that most sources of strong earthquakes (M ≥ 6.0), registered during the instrumental period of observation, are confined to zones in which a sharp change in the depth to the bottom of lithospheric magnetic sources occurs.

Depth to the Bottom of Lithospheric Magnetic Sources Beneath Northeastern Eurasia: Lithospheric Thermal Regime and Relation to Seismicity

Depth to the Bottom of Lithospheric Magnetic Sources Beneath Northeastern Eurasia: Lithospheric Thermal Regime and Relation to Seismicity

Variations of the effective elastic thickness evidence for a wide diffusive boundary between the North American and Eurasian plates in Siberia

Northeastern Eurasia is one of the least explored regions in the world. Very little geophysical data is available for this inaccessible area. Even the exact location of the plate boundary between Eurasia and North America remains a subject of ongoing debate. The effective elastic thickness (EET) of the lithosphere is a proxy for lithospheric strength and can provide insight into the thermal regime and tectonic processes. We have computed a high-resolution map of the EET for northeastern Eurasia using the fan wavelet coherence technique applied to the Bouguer gravity anomalies and topography/bathymetry data, appropriately adjusted to account for the influence of density variations within sediments. The results obtained provide insights into different tectonic regimes within this predominantly understudied region. In particular, we identify the boundary between the Eurasian and North American plates in Siberia as a rheologically weak diffusive zone extending from the Verkhoyansk and Sette-Daban Ranges to the eastern boundary of the Chersky Range. Unlike the Sette-Daban and Verkhoyansk Ranges, which were formed by plate collision and have an EET of 30–50 km, other mountainous regions have much lower EET values, usually less than 15 km. These areas have recently experienced tectonic activity that has weakened the lithosphere.

Measurements and Evaluations of the Atmospheric Transparency at Short Millimeter Wavelengths at Candidate Sites for Millimeter- and Sub-Millimeter-Wave Telescopes

Radio astronomical observations at millimeter and submillimeter wavelengths are a very important tool for astrophysical research. However, there is a huge area in northeastern Eurasia, including the whole Russian territory, which lacks sufficiently large radio telescopes effectively operating at these wavelengths. In this review, we describe our long-term efforts to find suitable sites for such radio telescopes in this area, that is, sites with good atmospheric transparency at millimeter and submillimeter waves. We describe methods and instruments used for measurements and evaluations of the atmospheric opacity. They include special radiometric systems, which are used for estimations of the atmospheric opacity in the transparency windows from the sky brightness measurements. Evaluation of the precipitable water vapor from such measurements by the artificial neural network is discussed. Other approaches use water vapor radiometers, global atmospheric models and signals of the Global Navigation Satellite Systems. To date, long-term radiometric monitoring has been performed at several candidate sites, and atmospheric conditions for many sites have been evaluated using global atmospheric models. Several sites with the best atmospheric transparency at millimeter and submillimeter wavelengths have been selected. They can be effectively used for astronomical observations, at least in the major atmospheric transparency windows at 1.3 mm and 0.85 mm. In general, the results show that northeastern Eurasia is a promising area for submillimeter astronomy. These results can also be used for space communications and radar systems.

The impact of climate change on seasonal glaciation in the mountainous permafrost of North-Eastern Eurasia by the example of the giant Anmangynda aufeis

This study examines the evolving dynamics of spring aufeis fields in the mountain permafrost zone of North-Eastern Eurasia, emphasizing their significance as indicators of permafrost-hydrogeological processes. Focusing on the representative Anmangynda river basin giant aufeis field, our research spans 1962 to 2022 and unveils temporal variations in aufeis characteristics.Over the historical period (1963–1990), the aufeis maximum pre-ablation area ranged from 4.3 to 6.8 km2, with a volume of 5.3 to 11.7 million m3. In the present era (2000–2022), these figures decreased to 3.5–5.4 km2 and 5.0–8.2 million m3, respectively. The region experienced heightened air temperatures and precipitation, with the most significant shifts occurring during early winter (October–December). Increased snow cover depth and earlier formation were also observed. Ground temperatures followed suit with an upward trend. Correlation analyses reveal a noteworthy link between average air temperatures from August to November and aufeis characteristics in both historical and current contexts. Moreover, solid precipitation and air temperatures in November and December displayed a moderate yet statistically significant correlation with aufeis size parameters during 2000–2022. Notably, no significant correlation emerged between aufeis characteristics and the Anmangynda River streamflow or liquid precipitation. This research underscores the interplay between climatic variables and aufeis dynamics, offering insights into the impacts of changing climatic conditions on the permafrost-hydrogeological system. The observed reduction of aufeis area and volume, coupled with the altered freezing and melting periods, align with broader cryospheric changes. As aufeis fields continue to evolve, this study highlights the complexities in their responses and their relevance as indicators of climate-driven alterations in the cryosphere. Further research is essential to fully unravel these intricate relationships and assess their implications for regional hydrology and ecosystems.

Cross-seasonal influence of the North Tropical Atlantic SST on soil moisture in Northeastern Eurasia

Cross-seasonal influence of the North Tropical Atlantic SST on soil moisture in Northeastern Eurasia

DEEP STRUCTURE AND FORMATION MODEL OF CONTINENTAL CRUST OF THE VERKHOYANSK FOLD- AND-THRUST BELT IN THE LATE MESOZOIC

The article considers the geological framework of a large orogenic structure in northeastern Eurasia - the Verkhoyansk fold-and-thrust belt (VFTB), formed in the Late Mesozoic on the eastern margin of the Siberian craton. Zoning of geopotential fields and the authors' interpretation of frequency-energetic characteristics along the 3-DV reference geo-physical profile provided the basis for modeling the deep structure of the VFTB and adjacent structures of the Siberian craton. There were identified structural zones of different geodynamic nature: the outer zone of the fold belt, underlain by the dropped margin of the craton; the inner zone of the VFTB with the oceanic crust at the base; the rear-zone structures formed by the Verkhoyansk complex in the subduction zone of the Uyandina-Yasachnaya island arc. In the Earth's crust of the VFTB there are distinguished two layers of approximately equal thickness: the lower one comprises a duplex system of complexes of the oceanic crust, and the upper one is built up by formations of the Verkhoyansk terrigenous complex, which have also undergone folding and duplexing. In parallel with thrusting of the upper terrigenous layer over the craton in the zone of collision between the VFTB structures and the Siberian craton margin there also occurred subduction of the lower layer of the VFTB under its margin. This led to an increase in thickness of the craton's crust by 5-10 km from below. The development of the Uyandina-Yasachnaya island arc system comprises two stages associated with blocking of the subduction zone and its transition towards the Oimyakon Ocean, which increased its area and complicated the structure. The paleosubduction zones and blocking structures are well-traced on the deep sections of reference seismic profiles.

D.G. Messerschmidt’s Collection of Siberian Antiquities in Drawings at the St. Petersburg Archive of the Academy of Sciences

This study focuses on the drawings of items collected during D.G. Messerschmidt’s fi rst multidisciplinary expedition to Siberia in 1719–1727. Pictures of the artifacts have been preserved among the documents held by the Academy of Sciences Archive in the personal papers of the traveler, which includes his fi eld journals, the appendices of his reports to the Pharmaceutical (Medical) Registry, and a large handwritten treatise “Sibiria Perlustrata” (1727), outlining the expedition’s fi ndings. In 1728, Messerschmidt’s archaeological collection was included as part of Peter the Great’s Siberian Collection, exhibited at the Kunstkamera. Watercolor and pencil drawings and engravings depicting the exhibits are identifi ed. Handwritten descriptions and drawings of the items have made it possible to a certain extent to reconstruct the fi rst encyclopedist’s Siberian archaeological collection, which perished during the 1747 fi re at the Kunstkamera. As Messerschmidt’s graphic works demonstrate, he documented items spanning the time from the Bronze Age to the Late Middle Ages and covering the territory from the Urals to the Trans-Baikal region, including things imported from Western Europe, China, and Central Asia. Also, he collected archaeological items representing virtually all cultures of the Minusinsk Basin. It is concluded that in the fi rst third of the 18th century, Messerschmidt’s collection was the world’s largest and most representative assemblage of artifacts from northeastern Eurasia.

Periglacial–Aeolian Polygonal Surface Structures in the Tibetan Plateau

Abstract—The surface pattern of permafrost area in the Tibetan Plateau, with 15–20 m polygons, resembles the patterned ground of the Arctic periglacial loess plains in northeastern Eurasia and North America. However, unlike the Arctic plains, it consists of semi-stabilized modern sand dunes, up to 2.5–3.0 m high, and U-shaped epigenetic ice wedge casts inherited from an ancient polygonal network on the surface of a 10–12-m terrace of the Yangtze River. The polygonal dunes and the U-shaped sand wedges were studied in the Yangtze head-waters in the vicinity of the high-altitude research station Bei-Lu-Xe. The polygons have desert pavement floors with ventifacts, composed of Late Pleistocene alluvial gravel and debris. The dunes and wedges consist of well sorted quartz-carbonate sand with an average grains size of 2.0–2.2 mm. Ground Penetrating Radar surveys in the area revealed the permafrost table at depths varying from 2 to 4 m below the dunes. The polygonal dunes may have formed by biogenic-aeolian deposition over an ancient system of ice wedges.

Ancient DNA of the Don-Hares Assumes the Existence of Two Distinct Mitochondrial Clades in Northeast Asia

Paleoclimatic changes during the Pleistocene-Holocene transition is suggested as a main factor that led to species extinction, including the woolly mammoth (Mammuthus primigenius), Steller's sea cow (Hydrodamalis gigas) and the Don-hare (Lepus tanaiticus). These species inhabited the territory of Eurasia during the Holocene, but eventually went extinct. The Don-hare is an extinct species of the genus Lepus (Leporidae, Lagomorpha), which lived in the Late Pleistocene-Early Holocene in Eastern Europe and Northern Asia. For a long time, the Don-hare was considered a separate species, but at the same time, its species status was disputed, taking into account both morphological data and mitochondrial DNA. In this study, mitochondrial genomes of five Don-hares, whose remains were found on the territory of Northeastern Eurasia were reconstructed. Firstly, we confirm the phylogenetic proximity of the "young" specimens of Don-hare and mountain or white hare, and secondly, that samples older than 39 Kya form a completely distinct mitochondrial clade.

Early Pragian Rhynchonellids (Brachiopoda) of West-Central Alaska and Northeastern Eurasia and Their Paleobiogeographic Significance

Early Pragian Rhynchonellids (Brachiopoda) of West-Central Alaska and Northeastern Eurasia and Their Paleobiogeographic Significance

Multi-year observations reveal a larger than expected autumn respiration signal across northeast Eurasia

Abstract. Site-level observations have shown pervasive cold season CO2 release across Arctic and boreal ecosystems, impacting annual carbon budgets. Still, the seasonality of CO2 emissions are poorly quantified across much of the high latitudes due to the sparse coverage of site-level observations. Space-based observations provide the opportunity to fill some observational gaps for studying these high-latitude ecosystems, particularly across poorly sampled regions of Eurasia. Here, we show that data-driven net ecosystem exchange (NEE) from atmospheric CO2 observations implies strong summer uptake followed by strong autumn release of CO2 over the entire cold northeastern region of Eurasia during the 2015–2019 study period. Combining data-driven NEE with satellite-based estimates of gross primary production (GPP), we show that this seasonality implies less summer heterotrophic respiration (Rh) and greater autumn Rh than would be expected given an exponential relationship between respiration and surface temperature. Furthermore, we show that this seasonality of NEE and Rh over northeastern Eurasia is not captured by the TRENDY v8 ensemble of dynamic global vegetation models (DGVMs), which estimate that 47 %–57 % (interquartile range) of annual Rh occurs during August–April, while the data-driven estimates suggest 59 %–76 % of annual Rh occurs over this period. We explain this seasonal shift in Rh by respiration from soils at depth during the zero-curtain period, when sub-surface soils remain unfrozen up to several months after the surface has frozen. Additional impacts of physical processes related to freeze–thaw dynamics may contribute to the seasonality of Rh. This study confirms a significant and spatially extensive early cold season CO2 efflux in the permafrost-rich region of northeast Eurasia and suggests that autumn Rh from subsurface soils in the northern high latitudes is not well captured by current DGVMs.

Giant Aufeis—Unknown Glaciation in North-Eastern Eurasia According to Landsat Images 2013–2019

Based on the analysis of Landsat satellite images over the period of 2013–2019, the number (6683) and total area (4529 km2) of giant aufeis fields (area ≥ 0.1 km2) were estimated for the territory of North-Eastern Eurasia. The contribution of aufeis runoff to river streamflow in different seasons was calculated for 58 hydrological gauges (area 523–526,000 km2). The contribution of aufeis and glaciers to water balance is compared. The aufeis resources vary from 0.4 to 4.25 km3 (or 3.7–11 mm) for individual basins of large rivers. They are at least 10.6 km3 in total or 5 mm of water depth on average for the study area. Aufeis annual runoff varies from 0.3 to 29 mm (0.1–22%, average 3.8%), with the share in winter runoff amount about 6–712% (average 112%) and the spring freshet 0.2–43% (average 7.1%). In general, the aufeis runoff exceeds the glacial runoff. The dynamics of aufeis formation are directly related to winter runoff, whose changes are observed in different parts of the cryosphere. The presented results are relevant for studying the impact of climate change on the hydrological cycle and its components in the permafrost regions of the Northern Hemisphere.