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Response of erosive mechanisms to climate change is of mounting concern on Beaufort Sea coasts, which experience some of the highest erosion rates in the Arctic. Collapse of intact permafrost blocks and slumping within sprawling retrogressive thaw complexes are two predominant mechanisms that manifest as cliff retreat in this region. Using aerial imagery and ground survey data from Pullen Island, Northwest Territories., Canada, from 13 time points between 1947 and 2018, we observe increasing mean retreat rates from 0 ± 4.8 m a−1 in 1947 to 12 ± 0.3 m a−1 in 2018. Mean summer air temperature was positively correlated with cliff retreat over each time step via block failure (r2 = 0.08; p = 0.5) and slumping (r2 = 0.41; p = 0.05), as was mean storm duration with cliff retreat via block failure (r2 = 0.84; p = 0.0002) and slumping (r2 = 0.34; p = 0.08). These data indicate that air temperature has a greater impact in slump-dominated areas, whereas storm duration has greater control in areas of block failure. Increasingly, heterogeneous cliff retreat rates are likely resulting from different magnitudes of response to climate trends depending on mechanism, and on geomorphological variations that prescribe occurrences of retrogressive thaw slumps.

Several fossil woods from Early Cretaceous sediments in Yumen City in northwestern North China Block, China, have been described. They belong to two fossil wood taxa, Piceoxylon yumeniense Zhou, Peng, Deng, Zhang and Yang n. sp. and Protophyllocladoxylon chijinense Zhou, Peng, Deng, Zhang and Yang n. sp. The well-preserved specimens yield secondary xylem with distinct growth rings. Piceoxylon yumeniense exhibits cross-field with taxodioid pits as well as two distinct xylem ray types. The bi- to triseriate rays are characterised by one or two horizontal resin canals with unequal uniseriate ends. Protophyllocladoxylon chijinense Zhou, Peng, Deng, Zhang and Yang n. sp. shows window-like cross-field pits, which are occasionally cupressoid and have uniseriate xylem rays. These fossil wood records improve our understanding of the fossil diversity, floral composition and palaeoclimate of the Xiagou Formation. Palaeoclimatic analysis of the palaeoxylogical assemblage indicates that the northwestern Gansu region predominantly exhibited a warm and wet climate condition, while a brief cooling event may have occurred in the region during the Early Cretaceous.

The mid-latitudes are exposed to outbreaks of Arctic cold air almost every winter. A stretch of below-normal temperatures prevailed over Eastern Europe, the Balkan Peninsula, parts of Mediterranean region and Turkey in the 2018/2019 winter. Extremely low temperatures associated with cold-air advection and considerable snowfalls were observed in parts of Turkey, especially during December and January. This study aims to investigate the association of observed cold anomalies with changes in the upper atmospheric conditions, especially considering polar vortex weakening, from December 2018 to January 2019, when the cold anomalies were more persistent over the country. The findings indicate that the observed cold anomalies during the two-month period were caused by several factors, including northerly and north-westerly Arctic air mass advection from an omega block pattern and polar vortex split, respectively. A persisting ridge across Western Europe caused meridional flow channels from the Arctic region to extend far towards the south. In addition, a deep upper low developed over north-eastern Europe and pushed a strong cold front towards east-central Europe, the Balkan Peninsula and Turkey. The polar vortex split was not as persistent across Eurasia as across North America but still led to cold anomalies, especially in early January 2019. Following the polar vortex split, an Arctic cold advection moved downstream and reinforced the southward displacement of the Siberian high, leading to extended cold anomalies and a stretch of below-normal temperatures over Turkey. An omega blocking pattern across the Western and Northern Europe also enhanced the northerly and north-westerly cold-air advection. In addition, a few intense cut-off lows, which moved across the eastern Mediterranean and Black Seas, intensified the local cold-air advection effects. The negative phase of the arctic oscillation corresponded well with the period of extremely cold temperatures observed over Europe during the 2018/2019 winter. The impact of the North Atlantic Oscillation variability on the cold anomalies portrayed a conflicting result for Turkey when compared to the Northern US, Canada and Northern Europe, where the cold-air outbreaks are usually associated with its negative phase. It is also likely that the decreasing Barents-Kara Sea ice favoured Ural blocking that led below-normal temperatures that impacted Eastern Europe and Turkey.

It is well documented that sediments record geochemical signatures that reflect the composition and tectonic setting of the rocks providing the detritus for them. This is true of the turbidites in ...

The 40Ar/39Ar dating of ultrapotassic rocks from Central Chukotka shows that these rocks are Early Cretaceous, and yields a narrow range of age variations (109 to 107 Ma), which correlates fairly well with the range of age variations of granitoids typical of the study area (117–105 Ma). There are thus grounds to suggest that the ultrapotassic magmas and granitoids resulted from the same geological process that can be identified from the material characteristics of the ultrapotassic magmas.In the modern concepts of the regional geological development, the formation of the granitoid and ultrapotassic magmas can be related to the continental lithosphere extension due to the collision of Eurasian plate and the Chukotka – Arctic Alaska continental block.Using modern genetic models based on the interpretations of the material characteristics of ultrapotassic magmas, it is possible to limit the number of genetic hypotheses and to relate the continental lithosphere extension to the processes that took place in the upper mantle of the study area.

An infrequent occurrence of sapphirine from metapelite rocks of the Cardamom hills of South India has been reported. This report of sapphirine may not be the first from the Southern Granulite Terrane (SGT) but is essentially from a new locality. The studied metapelites are silica-undersaturated devoid of garnet and the sapphirine symplectites. The symplectites of orthopyroxene + cordierite, orthopyroxene + K-feldspar + cordierite, orthopyroxene + sapphirine + cordierite ± K-feldspar ± biotite, orthopyroxene + biotite + cordierite + K-feldspar are discernible. The textural patterns show partial to complete pseudomorphism of the initially formed orthopyroxene and sapphirine and their succeeding decomposition to present stage. The relative XMg calculated for the key minerals show the trend as: Crd > Spr > Bt > Opx. The pseudosection modelling and the calculated P-T diagram drawn from the average bulk composition of the studied metapelite connote isothermal decompression with peak pressure and temperature conditions stable at ∼10 Kbar and ∼985 °C respectively. The assemblage reported in this study has an important bearing on the crustal evolution of the high-grade metamorphism exhumed from a deeper level of the crust.

The Xolapa Complex of southern Mexico preserves evidence of its connection with the Chortis Block of Central America. Orthogneisses yielded U-Pb protolith ages from 172 to 169 Ma and paramigmatites...

Few studies have determined the relationship between the thermal and methane anomalies associated with earthquakes. In this study, National Center for Environmental Prediction (NCEP) air temperature data and Atmospheric Infrared Sounder (AIRS) total column CH4 data were used to extract the thermal anomalies and methane concentration anomalies before 2008 Wenchuan earthquake. The Granger causality test is then used to support or disprove some conjectures that describe the relation between thermal anomalies and methane anomalies The results show that thermal anomalies appeared from May 5 to 14, 2008, and that methane anomalies appeared from May 12 to 28. Spatially, thermal anomalies occurred to the south of the epicentre in the area with the maximum secular block motion before the earthquake, and the methane anomalies occurred along the Longmenshan Fault as well as the south of the epicentre. The Granger causality results indicate that change in crustal stress caused the thermal anomalies, creating the escaping channels for the underground gases, and then lead to the methane anomalies. In terms of the lag of the methane anomalies, the methane anomalies are unlikely to have been the main cause of the thermal anomalies. However, in the area with large block motion before the earthquake and in the surface rupture area, the methane anomalies may have also influenced the local temperature.

The Qinling orogen, one of the most important orogens in Asia, belongs to the northeastern part of the Tethyan orogen. The architecture and processes of the Qinling orogen remain controversial. In this study, we present 15 new zircon U–Pb ages, 20 whole-rock geochemical and 46 Sm-Nd isotopic analyses, and 30 zircon Lu–Hf isotopic data for early Mesozoic granitoids in this orogen, combining with data from literature, to delineate the crustal architecture and processes of the orogen. A total of 181 zircon U–Pb ages show three phase (252–230, 230–198, and 190–185 Ma) of granitoids. The first-phase granitoids occur mainly in the westernmost segment of the orogen and formed in a subduction setting during the closure of the Mianlue Ocean (a northern branch of the Paleo-Tethyan Ocean). The second- and third-phase granitoids, distributed in the middle to eastern parts of the Qinling orogen, were generated in late syn-collisional and post-collisional tectonic settings, respectively. Whole-rock Nd and zircon Hf isotopic mapping of these granitoids yield six and seven isotopic provinces, respectively. These provinces display that the southern margin of the North China Block and the northern margin of the South China Block are dominated by ancient deep crust, that is, early Paleoproterozoic (2.3–1.8 Ga) and late Paleoproterozoic (∼1.7 Ga) components, respectively. By way of camparison, the North Qinling contains younger Mesoproterozoic [eNd(t) = −10.7 to −0.2; TDM = 1.4–1.0 Ga] basement, evidencing that it is an independent terrane different from the North China Block. The isotopic mapping also reveals a deep-seated NNE–SSW-trending zoned architecture that is approximately perpendicular to the WNW–ENE-trending of the orogen. This provides new evidence for the “Spaghetti Junction model” for the Qinling orogen. The old Nd (2.2–1.0 Ga, mostly 2.0–1.2 Ga) and Hf (2.3–0.8 Ga, mostly 2.0–1.2 Ga) model ages indicate that the continental growth in this orogen occurred mainly during the Paleoproterozoic and Mesoproterozoic, with only minor amounts of juvenile [eNd(t) = ∼0, TDM = ∼0.1 Ga] continental growth along the Shangdan and Mianlue sutures. These characteristics suggest that the Qinling orogen is dominantly formed by the collision of ancient continental blocks, distinct from some typical accretionary orogens, such as the Central Asian Orogenic Belt with voluminous juvenile crust.

Reworking or growth of the Hadean (>4.0 Ga) continental crust provides important hints in understanding the early evolution history of Earth. In this study, a comprehensive program of zircon U-Pb dating and Hf isotope analyses, as well as whole-rock major and trace element analyses, has been carried out on the Muzidian granitic gneisses from the northern Dabie orogen. The Muzidian gneisses are tonalite or granodiorite in composition, and have geochemical features resembling those typical of the tonalite-trondhjemite-granodiorite (TTG) suites. Zircon U-Pb dates range from ~2.5–2.4 Ga in the magmatic cores and from ~2.1–2.0 Ga in the metamorphic rims. Both the zircon cores and the rims have highly negative ɛHf(t) values of −25.2 to −19.9 and −31.0 to −28.1, respectively, corresponding to Tcrust of 4.25 Ga to 3.98 Ga, thereby, indicating that the protoliths of the orthogneisses in the northern Dabie orogen were formed by reworking of Hadean continental crust. This provides strong evidence for the presence of Hadean continental crust in the northern Yangtze block. These remnants of Hadean rocks resided in the continental crust of the Yangtze block for more than about 1700 Ma before being reworked. Compared to the ancient crustal components in the Kongling area of the Yangtze block, the Muzidian area along the northern margin of the Yangtze block seems to be more prospective for further occurrences of the Hadean zircon and/or rocks.

Even though meteorologists have been aware of atmospheric blocking for more than 100 years, it is a phenomenon still not well forecast or completely understood. Also, while there is not one standard accepted definition, there are some commonalities known about the understanding of blocking behavior. Blocking occurs less often than other destructive phenomena, but globally their occurrence has increased since the beginning of the century. The longevity of blocking means it can negatively impact agricultural and economic activity and human comfort by bringing extreme conditions not only to the areas where they occur but also to locations well upstream and downstream. Additionally, while it is known where blocking occurs and their general character has been well described, operational models still struggle to replicate the intensity and duration even though improvement has been noted in the timing and location of onset. Climatologically, models still underestimate their occurrence. In the last 40 years, investigators have used case study analysis and numerical and theoretical models to understand the onset and maintenance of blocking. Comparatively few have examined block decay. This review endeavors to cover the highlights of the history of blocking investigations, especially in the last few decades, in order to provide an understanding for a more general scientific audience.

In popular opinion, Sardinia is the only nonseismic region of Italy. Most researchers are likely to agree, up to a point. Geology-wise, the Sardinia–Corsica block is among the stablest areas of the Mediterranean. History-wise, up to 2011, only one Mw 5.1 event located offshore Sardinia was listed by Italian seismic catalogs (13 November 1948). Seismic networks record only a few, low energy (Mw “Low,” yes, but not “totally lacking.” We present the results of a recent reappraisal of Sardinian seismicity. We gathered information on three major earthquakes (1616, 1771, and the 1948–1949 sequence). Another sequence (January–March 1901) was re-evaluated, identifying its previously unknown main event. It was confirmed that some earthquakes (1870, 1906, 1922, and 1924) had low magnitudes and scarce to nil macroseismic effects, whereas some other turned out either very doubtful or wholly fictitious (1835, 1838, 1855, and 1898). The seismic hazard of Sardinia can now be reassessed on a sounder basis than before. We hope that our work will help the people of Sardinia to improve their awareness of living in a seismic land, if with a low level of seismicity.

Drilling, seismic and logging data were used to evaluate the hydrocarbon accumulation conditions of the mound-shoal complexes in the platform margin of the fourth member of Sinian Dengying Formation in the east side of the Mianzhu-Changning intracratonic rift in the Sichuan Basin. The four understandings are: (1) The platform margin belt of the Deng 4 Member can be divided into three sections, northern, middle and southern; the middle section is at the core of the Gaoshiti-Moxi paleouplift and the structural high now, while the southern and northern sections are at the slope of the paleouplift and the structural lows now; the three sections have similar development characteristics and reservoir features of platform margin mound-shoal complex. (2) In the margin of the east side of the rift, there are several faults nearly perpendicular to the platform margin belt, the faults divide the platform margin belt into rugged paleo-landform, and the high part developed platform margin mound-shoal complexes and the reservoirs are good in physical properties, while the low part developed inter-beach depression and no mound-shoal complexes, where the reservoirs are poor in physical properties. (3) The six groups of faults nearly perpendicular to the platform margin belt divide the platform margin belt into seven large mound-shoal complexes which have similar hydrocarbon accumulation conditions and accumulation evolution process and are rich in petroleum. (4) The inter shoal depressions between the mound-shoal complexes are characterized by tighter lithology, which can block the updip direction of the mounds and shoals at the lower part of the slope of the paleouplift and are favorable for the later preservation of mound-shoal gas reservoirs. This has been proved by Well Jiaotan 1 and Heshen 2 drilled successfully. The mound-shoal complexes on the platform margin of the structural slope area have a good exploration prospect.

The south coastal of Taizhou lies on the magmatic rock belt along the southeast coast of China, which has a complex regional geological structures, intense tectonic movement, and frequent magmatic activities. On the basis of the latest aeromagnetic data, combined with regional geology, gravity, and magnetic susceptibility information, integrated interpretation of the regional aeromagnetic anomalies and their reflected faults was completed. According to the block features in different zones of the reduction to the pole aeromagnetic data, the magnetic field characteristics and relationship with the structure division were described in detail. The different characteristics of the magnetic field are the concentrated reflection of tectonic movements, magmatic activities, and stratigraphic distributions; the fault structure, especially deep and large fault structures, was inferred and studied. The fault structures were mainly distributed in the NE, NNE, and NW directions, with approximately equal spacing between them. The magnetic anomaly is mainly characterized by the boundary, gradient zones, and beaded anomalies in a different magnetic field. The faults are not only important tectonic boundaries in this region but also tectonic belts that control the distribution of mineralization. Under the interaction of these faults, they form the basic structural pattern of the east-west zone and the north-south block. The NE faults have the largest scale and obviously control the different magnetic fields and magmatic activities. The results can provide a reference for further study of the distribution and activity characteristics of magmatic rocks in the coastal zone.

The properties of the solar constant variability are considered according to the results of satellite observations ( http://lasp.colorado.edu/home/sorce/data/tsi-data/ ). The obtainment of satellite data with an accuracy of 0.01% that is devoid of atmospheric influence allows a detailed analysis of variations in this index of solar activity and space weather for solar-activity cycles 21–24. The use of wavelet analysis demonstrates the properties of the 11-year cycle in the variation of the solar constant. With the exclusion of variations of the 11-year cycle, it is possible to study short-period processes in each solar cycle. The variations in the solar constant demonstrate their own local spectrum of power periods, which differs from the activity periods according to sunspot observations. The most significant decrease in the solar constant occurs during the passage in the center of the solar disk of large groups of spots and activity complexes that block the solar constant. Thus, the basic properties of the intrinsic variability of the solar constant differ from the properties of the magnetic cycle.

The western Qinling Mountains, located between the East Kunlun fault and the West Qinling fault, hold the key to investigating the outward expansion of the Tibetan Plateau. We use up-to-date GPS observations to derive high spatial–temporal resolution crustal velocity and strain rate fields for this region. Our results suggest that a series of NEE-trending faults bounding the eastern margin of the western Qinling Mountains experience right-lateral strike slip with low rates of ~ 1 mm/yr. In addition, our results suggest that crustal deformation of the western Qinling Mountains could be governed by a right-lateral shear zone trending NNE at a rate of ~ 6 mm/yr, producing a clockwise rotation of subblocks: left-lateral and right-lateral strike slip on the NWW-trending and NEE-trending faults, respectively. The eastward extrusion of the Tibetan Plateau along the western Qinling Mountains is limited further east. In contrast, the NNE-ward expansion of the northeastern Tibetan Plateau is the primary motion which extends through the western Qinling Mountains and the Longxi block. The results of this study improve our understanding of the outward expansion of the Tibetan Plateau influenced by the Indian–Eurasian collision.

This study focuses on physical modeling of interaction between the Indian and Pacific spreading axes, which resulted in separation of the Tasmania and Adelie blocks during the final stage of the Gondwana breakup, with separation of Australia and Antarctica. The Indian branch of seafloor spreading propagated eastward across the Archean–Mesoproterozoic lithosphere of the western part of Australia–Antarctica, whereas the Pacific branch moved westward through the Paleozoic–Early Mesozoic Fold Belt of eastern Australia–Antarctica. The experiments demonstrated that the interaction between the two spreading axes led to oblique extension (at an angle of 120°–130°) between two continents. At the same time, a rift branch formed between Antarctica and the Adelie Block, but did not developed further. Subsequent opening of the ocean occurred with sinistral strike-slip, which led to transpressional deformations of the Adelie Block and Sorell Basin within the Tasmania Block.

It is significant for identifying mass movement patterns to invert horizontal tectonic stresses at different depths underneath Tibet. In recent years, a large number of achievements focusing on two-dimensional tectonic stresses have been obtained from gravity data. However, three-dimensional tectonic stresses in Tibet are still unknown or debatable. Therefore, in the present study an improved method to multilayer horizontal tectonic stresses using gravity observations is developed. The inverted multilayer horizontal tectonic stresses are in agreement with those from previous studies. In addition, rich tectonic structure and development can be revealed from the inverted multilayer horizontal tectonic stresses: (1) the distribution of horizontal tectonic stresses at various depths shows strong correlation with that of the tectonic elements, where major faults and earthquake epicenters are corresponding with stress highs and the stable basins are consistent with stress lows. (2) the mass movement patterns of whole Tibet present clockwise, and the material movement directions in the west and east are approximately south-north and east-west, respectively. (3) in eastern Tibet, the eastward materials caused by the south-north extrusion between Indian and Eurasian plates are divided into two parts by the stable Sichuan Block, one flowing nearly southeast and the other moving almost northeast. The inverted multilayer horizontal tectonic stresses may provide direct evidences for mass movement patterns in Tibet.

We present high-resolution receiver function images along a 700-km long dense seismic array extending from northern Tibetan Plateau to the Alxa block, crossing the entire Qilian thrust belt (QTB). The dense stations, with less than ~2 km station intervals, allow the receiver functions to unveil unprecedented details of crustal structures across the northern frontier of the growing Tibetan Plateau. The migration image shows a thickened and strongly deformed QTB crust, with an uneven Moho and complex internal structures that are indicative of pure-shear shortening. The Alxa block, in contrast, has a thinner crust, a flat Moho, and little internal crustal deformation. These results suggest that the lateral growth of NE Tibetan Plateau is restricted by the strong Asian lithosphere, which shows no visible subduction beneath the Tibetan Plateau as previously suggested.

We examined the spatial distribution of intermediate-depth earthquakes in southern Alaska and the adjacent Aleutian Islands in relation to the deep fluid regime and volcanism. The distribution of earthquake hypocenters is studied in two variables, the depth of focus and the distance from the top of the slab. This approach shows that seismic activity is concentrated at 10–15 and 20–25 km from the top of the downgoing plate. Clusters of seismicity such as these cannot be due to slippage along the boundary between the continental block and the slab. In addition, extended structures of sharply increased seismic activity were found. Their location fits certain quasi-linear relations between pressure and temperature, and can mark metamorphic fronts in the subducted plate. Besides, the spatial earthquake distribution has a peak that appears to be related to active recent volcanism. It can be caused by active dehydration reactions in the subduction plate. These empirical findings testify in favor of the fluid-metamorphic model of earthquakes origin.

The petrogenesis and tectonic affinity of late Mesoproterozoic to early Neoproterozoic magmatic records in the Yangtze Block is important to understand its tectonic evolution within the context of ...

The study is focused on searching for spatial regularities in the occurrence of earthquake hypocenters in different geological settings in Northern Armenia. Tectonic-geomorphological indices are applied to define the tectonic activity of blocks composing the study area, which was manifested within a long period of time, starting from the neotectonic development period. The blocks are classified accordingly. The regional seismic activity is analysed considering the block structure of the study area. Earthquake focal mechanisms are determined, and dominant displacement trends are identified. Based on the comparative analysis of the blocks’ tectonic activity indicators and the locations of seismic events differing in strength, regular patterns of spatial distribution of seismic events are identified. It is established that the earthquake hypocenters of different strength occur in certain block structures; and the predominant types of movements in the earthquake hypocenters are largely determined by types of fault structures. It is emphasized that investigating the blocks’ neotectonic activity is important for discovering the general patterns of spatial distribution of seismic events.

The Rio Apa Block, a crustal fragment of 20,000 km2 in the southern portion of the Amazonian Craton, is a Paleoproterozoic terrain, making up the basement of the Neoproterozoic Paraguay Bel...

Extreme maximum (Tx) and extreme minimum temperature (Tn) frequency distributions during summer and winter for blocked conditions were analyzed within Turkey during the period from 1977 to 2016 by using observational data. The Tx (0.5–0.8%) and Tn (0.4–2.0%) frequencies vary between these values for the entire period during summer. However, Tx varies between 0.0 and 1.0, while Tn varies between 0.8 and 2.4 during winter. It is quite clear that atmospheric blocking has a greater cooling effect during winter. The maximum values for Tx and Tn are observed when the block center located within the easternmost sector impacting Turkey for summer. The maximum Tx frequency is observed in association with blocking in the westernmost sector, and the maximum Tn frequency is observed with blocking in the easternmost sector impacting Turkey during the winter season. Block intensity has almost no impact on Tx frequency although it has enhancing effect on Tn frequency during the summer. For winter, block intensity has a decreasing effect on both the maximum Tn and maximum Tx. The maximum Tx and Tn values increase with the block size for the summer. During the winter, the maximum Tx frequency decreases with the increase in the size of a blocking event; however, the greatest Tn frequency is observed within the 0°–30° E sector and lowest within the 30° E–60° E sector. The block duration has an enhancing influence on the maximum Tx value, while maximum Tn is observed during short-duration events and a minimum is observed during moderate-duration events during the summer season. For the winter season, the block duration has a decreasing effect for Tx frequencies and increasing effect for Tn.

The interannual variability of the mass transports through the Denmark and Fram Straits, and through the sections separating the Nordic Seas from the Atlantic Ocean and Barents Sea is studied on the base of numerical simulations performed with the use of the Argobased Model for Investigation of the Global Ocean (AMIGO). The model consists of a block for variational interpolation to a regular grid of Argo floats data and a block for model hydrodynamic adjustment of variationally interpolated fields. Additional numerical experiments were carried out in order to study the contribution of the wind forcing to the interannual variability of the transports: the real thermohaline fields corresponding to the particular time period were replaced by climatic ones (1) and by replacing the real wind forcing data with the climatic ones (2). Analysis of the numerical experiments results has shown that the variable wind stress forcing is the key factor determining the interannual variability of the water exchange between Atlantic, Nordic Seas, and Arctic Ocean.

Precipitation and temperature are two important factors associated to snow hazards which block the transport infrastructure and cause loss of life and properties in the cold season. The in-situ observations are limited in the alpine with complex topographic characteristics, while coarse satellite rainfall estimates, reanalysis rain datasets, and gridded in-situ rain gauge datasets obscure the understanding of the precipitation patterns in hazardprone areas. Considering the Karakoram Highway (KKH) region as a study area, a double nested Weather Research and Forecasting (WRF) model with the high resolution of a 10-km horizontal grid was performed to investigate the spatial and temporal patterns of temperature and precipitation covering the Karakoram Highway region during the cold season. The results of WRF were compared with the in-situ observations and Multi-Source Weighted-Ensemble Precipitation (MSWEP) datasets. The results demonstrated that the WRF model well reproduced the observed monthly temperature (R = 0.96, mean bias = −3.92°C) and precipitation (R = 0.57, mean bias = 8.69 mm). The WRF model delineated the essential features of precipitation variability and extremes, although it overestimated the wet day frequency and underestimated the precipitation intensity. Two rain bands were exhibited in a northwest-to-southeast direction over the study area. High wet day frequency was found in January, February, and March in the section between Hunza and Khunjerab. In addition, the areas with extreme values are mainly located in the Dasu-Islamabad section in February, March, and April. The WRF model has the potential to compensate for the spatial and temporal gaps of the observational networks and to provide more accurate predictions on the meteorological variables for avoiding common cold-weather hazards in the ungauged and high altitude areas at a regional scale.

This work presents the results of U–Th–Pb (LA–ICP–MS) geochronological study of detrital zircons from terrigenous deposits of the Olokit zone of the Baikal–Patom fold–thrust belt of the Siberian Craton. It was established that the age of deposits of the Olokit Formation is in the range of 0.86–0.72 Ga. Archean and Early Proterozoic rocks of the southern part of the Siberian Craton and the Neoproterozoic complexes of the Baikal–Muya belt were the sources of detrital zircons of the terrigenous rocks of the Olokit zone. There is no evidence of rocks that could have been the sources of Mesoproterozoic (1.08–1.46 Ga) and Late Paleoproterozoic (1.65 Ga) detrital zircons for the deposits of the Ondok paleo-uplift in the Olokit zone, in the Baikal mountain region, and in the Siberian Craton. The data obtained and the results of paleomagnetic reconstructions indicate that Siberia and Laurentia in the Meso- and Early Neoproterozoic were in a fixed position relative to each other; an unknown continental block composed of Mesoproterozoic rocks could have occupied the space between them.

Colima volcano (19.51 N, 103.62 W, 3860 m.a.s.l.) in western Mexico is well known for its frequent activity. Along with nearby Nevado de Colima, and Cantaro volcanoes are part of a volcanic complex rising in the middle of the Colima graben, a structure on the margin of the Jalisco Block, some one hundred km from the Middle America trench. The activity of Colima volcano is varied and usually accompanied by intense seismicity, mostly of volcano-tectonic events. To investigate several aspects of these earthquakes, we analyzed events recorded by the seismological network of Colima during the outbursts of 1998–1999, 2005, and 2009. Those periods, of varying intensity, lasted from several months to several weeks before and after a significant explosive event. The hypocenters, located with standard methods, appear in a broad region around the volcanic complex. To obtain a more accurate location of these events, we relocated the hypocenters using the method of double differences. A set of 1191 relocated events was obtained, providing improved locations, which show hypocenters clustered under the edifice of Colima volcano and do not seem to be related to any particular geological feature and, therefore, represent the volume stressed by magma’s intrusion. The focal mechanism of the relocated events shows a variety of fault plane orientations with a majority indicating dip-slip faulting.

This study is the first attempt to apply fault-based and time-dependent seismicity models cooperatively for probabilistic seismic hazard assessment (PSHA) of the Kerman and adjacent areas (54–59° E, 28.5–34° N). For this study, almost all available literature and databases have been investigated to compile reliable information reported as instrumental, historical, and paleoseismological events, together with the geometry and kinematics information for active faults. This information systematically is integrated and contributed to PSHA. Conditional probabilities of occurrence for earthquakes greater than the maximum earthquake from which its standard deviation is deducted (M > Mmax − σMmax) are computed based on a Brownian passage time (BPT) model. The spatial distribution of the time-dependent peak ground acceleration (PGA) has been calculated, and spectral accelerations have been computed for three selected cities (Kerman, Rafsanjan, Ravar), with 10% probability of exceedance in 50 years. The time-dependent PSHA map for PGA shows variations from − 21 along the Gowk fault to + 32% near the Sabzevaran fault segments in comparison with the corresponding time-independent PGAs. The difference between the time-dependent and time-independent PGAs at most parts of the study area is negligible, especially at sites farther away from the faults, where the differences vary from − 7 to + 7%. Moreover, the difference between the time-dependent and time-independent spectral accelerations for Ravar and Rafsanjan cities is insignificant. However, this difference at periods of 0.1–0.3 s is significant in Kerman city. The results of this study provide a stimulus for considering time-dependency assumption and fault-based approach in future earthquake-resistant constructions required in Kerman and adjacent areas.

The paper presents the results of GNSS observations, provided by the authors in 2010-2019 years, in the zone of contact of tectonic structures of the Siberian platform, West-Siberian plate and West-Sayan orogenic area. We presented the first time assessment of the velocities of modern horizontal movements and the structural-kinematic model of block movements in a southern sector of the Yenisei Ridge. This model enables to assess the geodynamic safety of disposal of high-level radioactive waste in granite gneisses rocks of the Nizhne-Kansk massif.

Many fundamental questions remain about the roles and effects of stationary forcing on atmospheric blocking. As such, this work utilizes an idealized moist general circulation model (GCM) to investigate atmospheric blocking in terms of dynamics, geographical location, and duration. The model is first configured as an aquaplanet, then orography is added in separate integrations. Block-centered composites of wave activity fluxes and height show that blocks in the aquaplanet undergo a realistic dynamical evolution when compared to reanalysis. Blocks in the aquaplanet are also found to have similar life cycles to blocks in model integrations with orography. These results affirm the usefulness of both zonally symmetric and asymmetric idealized model configurations for studying blocking. Adding orography to the model leads to an increase in blocking. This mirrors what is observed when comparing the Northern Hemisphere (NH) and Southern Hemisphere (SH), where the NH contains more orography and thus more blocking. As the prescribed mountain height increases, so do the magnitude and size of climatological stationary waves, resulting in more blocking overall. Increases in blocking, however, are not spatially uniform. Orography is found to induce regions of enhanced block frequency just upstream of mountains, near high pressure anomalies in the stationary waves, which is poleward of climatological minima in upper-level zonal wind, while block frequency minima and jet maxima occur eastward of the wave trough. This result matches what is observed near the Rocky Mountains. Finally, an analysis of block duration suggests blocks generated near stationary wave maxima last slightly longer than blocks that form far from or without orography. Overall, the results of this work help to explain some of the observed similarities and differences in blocking between the NH and SH and emphasize the importance of general circulation features in setting where blocks most frequently occur.

Paleoproterozoic granitoids provide crucial constraints on the tectonic evolution of the Yangtze Block, South China, and its reconstructed position in the Columbia supercontinent. Here, we report z...

A block sample goes through stress changes during and after sampling. Sensitive clays are affected by sample disturbance and stress changes have a great effect on sample quality. Reduction of the in-situ total stresses to zero causes a soil sample to develop a negative pore pressure. In an ideal situation, a block sample retains its negative pore pressure during sampling and storage, preventing it from swelling. To study this, five in-situ tests were conducted in which the pore pressure variations inside block samples were monitored during and after sampling. The pore pressure was measured continuously during a storage period of several days and the results were compared with tests on reconstituted clay in an attempt to simulate the same stress conditions as those in situ. Similar to the in-situ tests, the pore pressure inside the reconstituted samples was measured throughout the test. The findings suggest that the negative pore pressure in mini-block samples may be reduced in a matter of minutes or hours after sampling. Parallel testing on mini-block and reconstituted clay samples indicated that pore pressure dissipation had a negative effect on the preconsolidation pressure, constrained modulus and sample quality.

The elevation history of the Tibetan Plateau promises insight into the mechanisms and dynamics that develop and sustain high topography over tens of millions of years, as well as the contribution of uplift-related erosive flux to Cenozoic global cooling. The elevation history of the center and northern margin of the plateau have been historically less well-constrained than the southern margin. A diverse suite of techniques, each with their own biases and uncertainties, yield discrepant mid-Cenozoic elevation estimates (0–5 km). We reconstruct Paleogene to Miocene elevations of the Lunpola basin on the northern Lhasa terrane, the southernmost crustal block of the Tibetan Plateau, using stable isotope paleoaltimetry and clumped-isotope paleothermometry on lacustrine and pedogenic carbonates, integrated with previously published compound-specific n-alkane-derived hydrogen isotopes. Paleo-elevation estimates for the Lunpola basin (∼3.1–4.7 km) demonstrate that the northern edge of the Lhasa Block attained high elevation prior to ∼24 Ma and potentially by the Early Eocene (

In this research, daily rainfall data from a 29-year statistical period (1990–2018) for 30 synoptic stations of north–eastern Iran were obtained by statistical methodology from the Iranian Meteorological Organization (Tehran). From these maps, the clustering system (blocking) and the study of various atmospheric blocking systems were used to study and investigate the climate (dry and humid phenomenon) of north–eastern Iran. Drought and mildew is an important environmental issue, so recognizing its characteristics is very important. The most common monitoring of drought conditions is the drought index. The SPI is applicable because of its simplicity, versatility and applicability in any type of climate. Therefore, it is a well-known index for dry drought monitoring. Therefore, it is used for drought monitoring and estimation of its occurrence in the north–eastern region of Iran, in the dry area and mountainous regions of Iran. The SPI was used in combination with the Markov chain, and the continuity, intensity and abundance of drought and mildew for the 12 months of the year were studied and examined. The results of this study showed the effect of the tongue of the Siberian high pressure and the tropical highlands of Azure and the Tibetan plateau (Himalayan mountain range) and the Mongolian plateau and Siberian plateau The Arabian Peninsula has been involved in the creation of a block diagram (blocking of atmospheric conditions) whose intrusion and divergence have prevented the low pressure of the Mediterranean to the north–east of Iran and play an effective role in creating the block in the dry periods, and the continuation dry and wet periods are visible on the Iranian plateau.

Volcanic effusive facies (VEF) and volcanic conduit facies (VCF) are two important facies units that can be found in a volcanic reservoir or edifice. Because VEF and VCF generally exhibit opposing seismic reflection characteristics, few studies have been applied to simultaneous characterization of the two facies in seismic data. We have developed an integrated 3D seismic data attribute-based characterization technique of VEF and VCF in the BZ34-9 Block, Bohai Bay Basin, eastern China. Our method is based mainly on the 3D visualization of a thresholding display so as to separately describe the strong-amplitude reflection of the VEF with its original amplitude attribute and the weak-amplitude chaotic reflection of the VCF with its variance-cube attribute. The detailed workflow comprises four steps, including seismic facies analysis, characterization of the VEF, characterization of the VCF, and merging a display of the two volcanic-facies units. The resulting 3D image of the different volcanic facies described in the BZ34-9 Block should be able to be viewed from any perspective for a better understanding of the related genesis mechanisms of the first and second members of the Shahejie (Es12) and Dongying Formations (Ed). In total, 28 volcanic edifices have been identified on the basis of the proposed method, among which three volcanic edifices exhibited inherited eruptions, in the Es12 and the Ed. Volcanic edifices in the Es12 are distributed locally in the central part of the BZ34-9 Block, showing a central eruption style, whereas those of the Ed are characterized by a widespread distribution in the southern gentle slope of the BZ34-9 Block, revealing a composite, center-fissure eruption style. The approach should be convenient to operate and would be effective in characterizing different volcanic facies simultaneously. This application can serve as a useful reference for other basins or regions with obvious volcanic influence.

[Abstract The influence of climate on mountain denudation has been the topic of an intense debate for two decades. This debate partly arises from the covariation of rainfall and topography during the growth of mountain ranges, both of which influence denudation. However, the denudational response of this co‐evolution is poorly understood. Here, we use a landscape evolution model where the rainfall evolves according to a prescribed rainfall–elevation relationship. This relationship is a bell curve defined by a rainfall base level, a rainfall maximum and a width around the rainfall peak elevation. This is a first‐order model that fits a large range of orographic rainfall data at the ca. 1‐km spatial scale. We carried out simulations of an uplifting block with an alluvial apron, starting from an initially horizontal surface, and testing different rainfall–elevation relationships. We find that the denudation history is different from that with constant rainfall models. The results essentially depend on the ratio between the final steady‐state summit elevation Hss and the prescribed rainfall peak elevation Hp. This ratio is hard to predict because it depends on the transient coupling of rainfall and elevation. We identified three types of results according to Hss/Hp. If Hss/Hp > 4 (Type I), the denudation rates peak when the summits reach values close to Hp. If Hss/Hp > 1.5 and < 4 (Type II), the denudation is strongly accelerated when the elevation of the summits approaches Hp, and then the denudation increases slowly towards the uplift rate. If Hss/Hp < 1.5 (Type III), the denudation evolution is similar to situations with constant and homogeneous rainfall. In the Type I and II experiments, the mountain top is subjected to aridification once the summits have passed through Hp. To adapt to this reduced rainfall, the slopes increase. This can lead to a paradoxical situation where the mountain relief increases faster, whereas the denudation increases more slowly. The development of orographic precipitation may thus favour the stability of the mean denudation rate in a rising mountain. Despite the model limitations, including a constant rainfall–elevation relationship, our study suggests that the “classical” exponential increase in the denudation rate predicted by constant rainfall models is not the common case. Instead, the common case involves pulses and acceleration of the denudation even in the absence of uplift or global climate variations., The development of a precipitation peak at some elevation within mountain catchments appears to be a crucial factor that controls the denudation and topographic evolutions of a mountain. If the precipitation peak is located at low or medium elevation when the mountain has reached a dynamic equilibrium, the model predicts that denudation has strongly accelerated (b) in the early times of the mountain uplift, or even passed by a maximum resulting in a pulse of sediment outflux to basins (a). If the precipitation rate does not have a maximum in the mountain, it can be deduced that the denudation has not evolved differently from cases where the precipitation rate is constant (c). These results can be used to re‐examine the interpretation of sediment flux variations in real cases based on the current distribution of precipitation rates with altitude in mountain ranges. ]

Large amounts of data accumulated in ecology and related environmental sciences arouses urgent need to explore useful patterns and information in it. Here we propose coclustering-based methods and a temperatures-photoperiod driven phenological model to explore spatio-temporal differentiation in long-term spring phenology in China. First, we created the first bloom date (FBD) dataset in China from 1979 to 2018 using the extended spring indices and China Meteorological Forcing Dataset. Then we analyzed the dataset using Bregman block average co-clustering algorithm with I-divergence (BBAC_I) and kmeans algorithm. Such analysis delineated the spatially-continuous phenoregions in China for the first time. Results showed three spatial patterns of FBD in China and their temporal dynamics for 40 years (1979–2018). More specifically, overall late spring onsets occur in 1979–1996, in which areas located in Jiangxi, northern Xinjiang and middle Inner Mongolia experienced constant changing spring onsets. Overall increasingly earlier spring onsets occur in 1997–2012, in which areas located in Fujian, Hunan and eastern Heilongjiang experienced the most variable spring onsets. Stable early spring onsets over China occur after 2012. Results also showed 15 temporal patterns of spring phenology over the study period and their spatial delineation in China. More specifically, most areas in China have the same FBD category for 40 years while northern Guizhou, Hunan and southern Hubei have the same category in 1979–1997 and then fluctuate between different categories. Finally, our results have certain directive significance on the design of existing observational sites in Chinese Phenological Network.

We investigate a record-breaking heat wave in southern China (SC) and explore its association with the South China Sea (SCS) summer monsoon (SCSSM), using station observations and various reanalysis products. This heat wave event started in mid-May 2018 and persisted more than 15 days, when the maximum air temperature anomaly exceeded 6 °C. Meanwhile, the onset of the SCSSM was extremely late in 2018, primarily due to the intrusion of easterly winds over the SCS. We show that the anomalous easterlies over the SCS associated with the delayed SCSSM could block the moisture transport from the tropical oceans to SC, which led to decreased rainfall, increased surface radiation, and elevated probability of heat wave in SC during May 2018. Further analysis reveals that both SC heat waves and SCSSM were significantly affected by the Pacific subtropical high (PSH). The westward extension of the PSH can hinder the establishment of SCSSM via inducing easterly anomalies over the SCS, which reduces SC rainfall and results in a drier surface condition. Moreover, the westward displacement of the PSH may cause anomalously high pressures, descending air motions, and divergent winds over SC, which triggers above-normal air temperatures that are conducive to the occurrences of SC heat waves. This study also underlines the importance of Eurasian planetary wave trains in bridging the upstream climate variability and the changes in PSH during boreal spring, which could be used to improve the intra-seasonal predictions of SC heat wave and SCSSM onset.

NE Asia has experienced Significant extensional events in the Early Cretaceous, including related volcanic rocks, extensional basins, metamorphic core complexes (MCCs), and low-angle detachment fau...

The focal mechanisms of earthquakes in the Javakheti Highland for the period 1971–2015 were constructed for separate time intervals: 1971–1973, 2001–2004, 2006–2009, 2010–2012, and 2013–2015. The method of averaged mechanisms was used, which jointly processed data on the distribution of the signs of the first P-wave arrivals of Javakheti Highland earthquakes with various energies. As a result of comparing the obtained focal solutions with the tectonic structure of this region, five blocks with different directions of compression–extension forces were identified along the boundaries of active faults in the study area. The prevailing types of slip in earthquake foci in each block for each of the above time intervals were identified. The nature of the source mechanisms for weak earthquakes that preceded the 1986 Paravan earthquake was studied. It was established that shortly before this event, the prevailing type of slip changed from shear to reverse-fault with a shear component.

The Bohai Bay Basin, located in the eastern North China Block, is an important sedimentary basin for studying the Quaternary climate and environment of northern China. Although sporo-pollen analyses have been used to study the paleoclimate, quantitative research via geochemistry had not been conducted. The sedimentary sequence, geochemistry, and mineralogy of Quaternary sediments from core GJ01 in the Yongding River fluvial plain, northern Bohai Bay Basin, were studied to determine their provenance and investigate climate change during the Quaternary. The stratigraphic sequence of the Quaternary was mainly formed by fluviation by a meandering river, showing a typical dual structure. The sediments have relatively high SiO2 and CaO concentrations, and low Al2O3, Na2O, and Fe2O3T concentrations. In terms of trace elements, most large ion lithophile elements are slightly enriched, and Rb and K concentrations are close to those of post-Archean Australian shale (PAAS); most high field strength elements are slightly to moderately depleted. Rare earth elements (REEs) vary significantly, with light rare earth elements (LREEs) obviously enriched relative to heavy rare earth elements (HREEs). A slightly negative Eu anomaly is present, with nearly no Ce anomaly. Mineralogical analysis shows that the main minerals in the fine-grained sediments are quartz, plagioclase, and K-feldspar. The geochemistry and mineralogy of the sediments indicate that the main provenances were recycled sedimentary rocks and felsic igneous rocks. The sediments have low chemical index of alteration (CIA) values, demonstrating that the source rocks underwent slight weathering. The mean annual precipitation and temperature of the studied area during the Quaternary varied from 531 to 875 mm and from 4.1 to 11.8 °C, respectively.

Models are continuously developed at numerical weather prediction (NWP) centres to improve forecast skill, with new operational model configurations adopted every few years. The parameterisations of diabatic processes are probably the most frequently updated part of NWP models as they are crucial for accurate weather predictions and contain uncertainties in their formulation. The impact of model developments is assessed here in forecasts from the Met Office’s weather forecast model initialised throughout the North Atlantic Waveguide and Downstream Impact Experiment field campaign period in autumn 2016. Planned model parameterisation developments are considered, together with an‘inexpensive coupled’ forecast with daily updating of the sea surface temperature and sea-ice fraction. Forecasts produced from the coupled system have, on average, indistinguishable skill from the control forecasts, suggesting the benefits of coupled atmosphere-ocean NWP systems can be small. In contrast, a reduction in forecast error (~4%) is identified in forecasts produced using an upgraded convection scheme. Periods of low forecast skill during the study period are shown to be associated with the onset and decay of blocking events and increased diabatic heating of air masses reaching the upper troposphere. In forecasts of a specific block development case that was not accurately predicted in any of the experiments or in the operational ensemble forecast from the Met Office, the representation of diabatic heating in the warm conveyor belt of an upstream cyclone is shown to moderate the subsequent block development: forecasts in which the heating is stronger generally have a more-amplified blocking ridge and amplified heating contributions from all parameterisations as diagnosed using diabatic tracers. Hence, we demonstrate that plausible changes to the representation of several different diabatic processes in models can impact forecast block development via changes within upstream cyclones.

South Korea forms the Korean Peninsula and is considered to be tectonically more stable than the other regions of Eastern Asia. Global Navigation Satellite System (GNSS) sites installed in the country contribute to geoscientific studies on contemporary deformation, strain pattern, and current kinematics of tectonic blocks. In the current study, we used long-term GNSS measurements (from 1 January 2000 to 31 December 2018) to study block-wise geodetic deformation and strain pattern of the country, including the co-seismic effect of the 2011 Tohoku-Oki (TO) Earthquake. Measured velocities of GNSS sites are modelled via exponential smoothing method to analyse the GNSS time-series and obtain the secular tectonic crustal deformation. The analysis of strain pattern and vertical displacements indicates that extensional deformation followed compressional deformation from the northern Korean blocks to the southern Korean blocks. Finally, we examined the angular velocity and pole of rotation of the South Korean blocks using pre-seismic and post-seismic displacements of the GNSS sites. The results indicate that the angular velocity of the northern blocks was lower, while the southern block velocity is higher after the TO earthquake. We believe that the integrated approaches applied in the study would provide better insights into the active deformation of South Korea.

The Crosby Warren Field is located onshore the UK, south of the Humber Estuary. It was discovered by RTZ Oil & Gas with the CW-1 (L46/12-3) well in 1986. The oil reservoir is Carboniferous, Namurian, Beacon Hill Flags sandstone, with gas found in Namurian sandstones of the Rough Rock, and the discovery well originally flowed waxy 40° API oil at rates of 45 bopd, which increased to nearly 700 bopd following fracture stimulation. The Beacon Hill Flags are a 10 m-thick group of laminated sandstones within a substantial gross thickness of sandstones, silts, muds and occasional thin claystones. The expected ultimate recovery for the field will be about 0.9 MMbbl of oil and 0.7 bcf of gas. Almost all of the oil and gas have already been recovered, and end of life for the field is expected to be in 2022.

The South China Block (SCB) consists of the Yangtze and Cathaysia Blocks which, in the northeast, are separated from each other by the Jiangnan Orogen. The southward continuation of the Jiangnan Orogen into the Youjiang Basin remains much debated. Here, we present detailed petrological, chemical and isotope evidence from the Late Jurassic (~159 Ma) Yangtun and Liuliang high-Mg andesites (HMA), eastern Youjiang Basin, to place important constraints on an ancient subduction event. These HMA are enriched in large ion lithophile elements and depleted in Nb-Ta-Ti, with negative whole-rock eNd(t) and zircon eHf(t) values, similar to Neoproterozoic high-Mg rocks that occur in the eastern Yangtze Block. Considering the distance of our study areas to penecontemporaneous Pacific or Tethyan trenches, we infer that these HMA derived from a metasomatised lithospheric mantle preserved beneath the eastern Yangtze Block, which was associated with a Neoproterozoic subduction event. The Late Jurassic HMA in the eastern Youjiang Basin provide potential clues for the southward continuation of the Jiangnan Orogen into the basin.

The Alba Field is a relatively heavy oil accumulation lying in an Eocene deep-water channel complex in Block 16/26a of the Central North Sea. With an estimated 880 MMbbl in place, the reservoir is characterized by thick, high net/gross sands with excellent reservoir properties and rock physics favourable for seismic property detection. The field has been developed by horizontal production wells, with pressure support provided by seawater injectors. After 24 years of production, more than 427 MMbbl have been recovered. Over the course of the development, the results of development drilling and improved reservoir imaging from seismic have revealed greater reservoir complexity than anticipated at sanction. The highly irregular reservoir geometry is likely to reflect the internal stacking patterns of channel elements within the channel complex that are locally overprinted by post-depositional remobilization. This increased reservoir complexity has required more wells to effectively drain the expected volumes. Despite this, recovery has exceeded estimates from the initial field development plan, reflecting an extremely efficient waterflood. 4D seismic spectacularly images extensive sweep away from injectors and excellent reservoir connectivity. Throughout the development, the application of seismic technologies has been a key enabler for effective reservoir management and, looking forward, maximizing value.

The Culzean Field is situated 240 km east of Aberdeen in Block 22/25a. The field was discovered in 2008 by well 22/25a-9Z targeting a tilted fault block, encountering lean-gas condensate in the fluvial Triassic Skagerrak (Joanne Sandstone Member) and the Jurassic Pentland formations. The field is high-pressure–high-temperature (HPHT) with initial conditions of 936 Bar (13 575 psi), 176°C (348°F) and charged with a lean-gas condensate. Development of the field was sanctioned in 2015 and is the latest UK HPHT field to be developed with start-up in mid-2019. The field development plan comprises production from six development wells drilled from a wellhead platform with bridge connections to a central process platform with accommodation on an additional bridge-linked utilities and living quarters platform. Gas is exported to shore via the Central Area Transmission System pipeline and produced condensate is exported via the floating storage and offloading vessel ‘Ailsa’. Production is expected to reach a plateau production rate in the order of 100 000 boepd with an overall recovery of up to 300 MMboe.

The Stella Field is located in UKCS Block 30/6a, c. 230 km SE of Aberdeen. Stella Field is a four-way, dip-closed and salt-cored dome with a 600 ft gas-condensate column underlain by a 250 ft oil column within the 5–30 ft thick Paleocene Andrew Sandstone Member. Oil is also present in the underlying chalk reservoirs of the Danian Ekofisk and Maastrichtian Tor formations. Following the discovery of the field in 1979 there have been three phases of appraisal followed by the recent development, with first oil in February 2017. The field development has been challenging as the 38-year gap between discovery and first oil illustrates. Principal challenges have included structural undulations and radial faulting combined with a thin primary reservoir, variation in hydrocarbon, compartmentalization and depletion relating to producing fields. These issues have been reviewed following the latest drilling results and ideas on the petroleum geology updated. Block 30/6a, containing the Stella Field, was originally awarded to Shell/Esso in the first Licensing Round in 1964 as part of multi-block licence P011. The current Stella P.011 licence holders are Ithaca Energy (UK) Limited (operator) with 54.66%, Dyas UK Limited with 25.34% and Petrofac GSA Limited with 20%.

The Glenlivet Field, located in Block 214/30a within the Faroe–Shetland Basin, was put on production in August 2017. It lies approximately 70 km NW of the Shetland Islands, in a water depth of c. 440 m. The development consists of two subsea wells that produce gas condensate from the Paleocene Vaila Formation, which comprises deep-water turbidite deposits with excellent petrophysical properties. It is part of a joint development scheme along with the Edradour Field that sees the commingled multiphase production transported to the Shetland Gas Plant via tie-back to the pre-existing Laggan–Tormore flowlines. Glenlivet is operated by Total E&P UK Ltd under the P1195 licence since September 2014 with Ineos E&P (UK) Ltd and SSE E&P UK Ltd as partners.