West Slope Research Articles

Geotechnical Justification for Designing Landslide Prevention Measures

Abstract When designing anti-landslide measures, slope stability assessment is an important factor and is determined by conducting comprehensive engineering and geological studies on a slope with potential landslide risks. The results of correct engineering and geological justification for the design of anti-landslide measures lead to the preservation of the structure and safe operation of infrastructure facilities. Our experience shows that to eliminate the negative effects of landslide processes, it is necessary to accurately determine the engineering and geological conditions of the slope, including the stability of the slope, taking into account natural dynamic phenomena (seismicity of the territory and tectonic processes) and, if possible, to see the complete elimination of the causes that lead to landslide processes when developing anti-landslide measures. To achieve these goals, the geotechnical justification of the design is the only correct solution. Geotechnical justification of protective measures intended to protect the structural elements of the Baku-Russian Federation State Border highway, which is part of the north-south transport corridor and passes through the foot of a potentially landslide-hazardous slope west of the city of Shabran, is one of the most important conditions that increase the effectiveness of these measures. On a slope located 1500 meters southwest of the current research area, the results of our scientific research were not properly utilized and many of our warnings were not heeded, resulting in a landslide during construction, leading to serious damage to the road's structural elements (Fig. 1) and additional costs. This event once again confirms that landslides are the most common natural and man-made processes that pose a threat to the safe operation of infrastructure facilities, civil and industrial construction in mountainous and foothill areas (Shiraliyev et al., 2024)

The velocity extraction and feature analysis of glacier surface motion in the Gongar region based on multi-source remote sensing data

The movement of glaciers plays a crucial role in environmental and geological processes, significantly influencing the formation and dynamics of ice bodies. This study leverages feature tracking technology to analyze optical and Synthetic Aperture Radar (SAR) remote sensing imagery, specifically GF-1 optical images and GF-3, Sentinel-1 SAR images, captured during the 2020 to 2021 ablation season in Gongar. The aim was to quantify glacier surface velocities and to evaluate the comparative effectiveness of different remote sensing modalities in capturing these dynamics. Our findings indicate a strong consistency in the spatial distribution of glacier surface velocities derived from diverse remote sensing data sources, with high-precision optical imagery (GF-1) yielding the most accurate velocity measurements, followed by Sentinel-1 SAR data. Notably, large glaciers in Gongar exhibited rapid movements, with an average velocity of 0.16 m/d, primarily at elevations between 4,500 and 6,500 m. The fastest velocities were recorded at approximately 4,500 m elevation. Glaciers with inclines ranging from 10° to 60° displayed the highest velocities within the 20°–30° slope range. It was observed that glaciers on the southeast slope moved faster, exhibiting the highest average surface velocity, in contrast to those on the west slope, which moved more slowly. The surface velocity of the ice tongue region of Krayaylak Glacier that the largest glacier in Pamir, was observed to be lower than 0.6 m/d, indicating a slow movement speed. The study also reveals that the effectiveness of different remote sensing data in detecting glacier velocity in Gongar, with high-resolution data more accurately capturing surface velocities in melting areas or those with slower movement. This study underscores the importance of multi-source remote sensing data in understanding glacier dynamics and contributes valuable insights into the mechanisms driving glacier movements.

Discussion on Deep Geothermal Characteristics and Exploration Prospects in the Northern Jiangsu Basin

The Northern Jiangsu Basin (NJB), located at the northeast edge of the Yangtze block, is not only rich in oil and gas resources but also contains abundant geothermal resources. Nevertheless, the distribution of geothermal resources at medium depth in the NJB is still unclear due to its complex geological structure and tectonic–thermal evolution process, which restricts its exploitation and utilization. The characteristics of the geothermal field and distribution of geothermal reservoirs within the NJB are preliminarily analyzed based on available temperature measurements and geothermal exploration data. The prospective areas for the exploration of deep geothermal resources are discussed. The analysis results show that (1) Mesozoic–Paleozoic marine carbonate rocks are appropriate for use as principal geothermal reservoirs for the deep geothermal exploration and development within the NJB; (2) the geothermal field is evidently affected by the base fluctuation, and the high-temperature area is mainly concentrated at the junction of the Jianhu uplift and Dongtai depression; (3) the southeast margin of Jinhu sag, Lianbei sag, the east and west slope zone of Gaoyou sag, the low subuplifts within the depression such as Lingtangqiao–Liubao–Zheduo subuplifts, Xiaohai–Yuhua subuplifts and the west of Wubao low subuplift, have good prospects for deep geothermal exploration.

The spatial differentiation of human-environment relationship in mountain tourism destination, based on the image data of Landsat-8

Mountain is the most traditional tourism destination in China. On the basis of analyzing the particularity and its spatial differentiation of human-environment relationship in mountain tourism destination, this paper conducts empirical analysis in Yulong Snow Mountain by land use type classification. Firstly, ENVI is used to preprocess the Landsat-8 images of the research area. Then the visual interpretation is performed by ArcGIS to classify land use types. Based on the above, the differentiation status of human-environment relationship is analyzed. It concluded that: (1) Under the influence of natural factors such as piedmont, climate, altitude, gradient, slope, geological environment, and geomorphic characteristics, the uneven spatial distribution of human-environment relationship in mountain tourism destination is greatly affected by vegetation, rainfall, heat distribution, wind direction, suitability for human activities, and especially the topography; (2) The Yulong Snow Mountain forms three distinct levels of spatial differentiation in human-environment relationships between the east and west slopes, between high, medium and low elevations, and between different gradients.

The effect of lateral thrust on the progressive slope failure under excavation and rainfall conditions

Large landslides can involve the multiple failures of regional slopes. To understand the effect of lateral thrust caused by the failure of one slope on its surroundings, the failures of two adjacent highway slopes in Guangdong Province, China, were investigated in detail. The interactive failure processes and landslide morphological characteristics of the two slopes were first analyzed based on the on-site investigation. Then, a plane mechanical model of a large-scale slope was established to evaluate the significant influence of the lateral thrust generated by the west slope acting on the east excavated slope. Furthermore, the extrusion effect of the west slope was modelled under the alternate excavation disturbance and rainfall by transferring the thrust forces onto the interface elements, and the induced failure mechanism and instability mode of the east slope under lateral thrust were reproduced numerically. The results show that the compression-shear failure occurred at the middle and rear slope bodies because of the lateral thrust, which led to the formation of a thrust landslide and the final instability of the east slope.

Diurnal variation in short‐ and long‐duration precipitation within the Dabie Mountain region in Central China

AbstractDiurnal variation in regional precipitation in Central and East China has been broadly identified in previous study. This study focused on clarifying not only the differences in the diurnal variation concerning the local precipitation occurred in the Dabie Mountain (DBM) region and the regional precipitation occurred through the middle‐lower reaches of the Yangtze River Basin, but also the association mechanism between diurnal variation in local precipitation with differing duration and diurnal modulation of ambient circulations driven by large‐scale background synoptic force or local‐scale orographic force of the DBM. It was found that cases of short duration precipitation (SDP, duration <6 h) and cases of long duration precipitation (LDP, duration ≥6 h) exhibit vastly different patterns of diurnal variations. Further investigation revealed that the primary pattern of the ambient circulation responsible for SDP and LDP is the recycling transformation between a closed cyclonic circulation to a cyclonic wind shear, and the recycling movement of a closed cyclonic circulation in the lower troposphere respectively. Although the diurnal variation in LDP exhibited greater orographic regional differences between the west slope (WS) region and the east slope (ES) region in comparison with that of SDP, topographical sensitivity experiments of the DBM and detailed analysis of background synoptic systems associated with LDP indicated that this regional orographic difference shows closer association with eastward propagation of background synoptic systems than orographic effects of the DBM. Respective strengthening of upward vertical motion at different levels of the troposphere during diurnal variation in SDP and LDP cases provide substantial evidences to reconfirm the close association with orographic force in lower the troposphere for SDP cases and background synoptic force in middle troposphere for LDP cases. Further quantitative diagnosis also confirmed that the orographic effects of the DBM is conducive to cause marked differences in the diurnal variation in SDP cases between the WS region and the ES region via adjustment of the upslope wind over the former and the circumventing wind over the latter.

A revision of Silurian corals (Anthozoa: Heliolitoidea) from the collection of the National Museum of Natural History, NAS of Ukraine (Kyiv)

The collection of Silurian heliolitoid corals revised in this study has been assembled by the first author (V.G.) for four decades. The material was collected predominantly from Silurian outcrops and borehole cores in the Middle Dnister area. Some of the specimens were found in Belarus and Moldova during field works and field trips. The scientific works were part of the projects elaborated by a collective of scientists from the Institute of Geological Sciences, NAS of Ukraine and Taras Shevchenko National University of Kyiv. The working group consisted of geologists who graduated from the university in 1965 to 1970. Professors M. M. Klushnikov and O. L. Einor were our advisors. P. D. Tsegelnjuk was the oldest and the leader of the group. The collecting of specimens started in 1966 and now is ready to summarise the results. In the last fifty years, a large collection of fossil cnidarians from Silurian deposits has been assembled in the course of long-term geological field expeditions organised to study outcrops, cores of boreholes, and collect fossils. More than fifty outcrops and one hundred boreholes were studied in the territory of the Podillian region and the west slope of the Ukrainian Shield from Volyn to Snake Island. The collection comprises nearly ten thousand samples and 6000 thin sections of cnidarians. The total number of the studied samples belonging to Heliolitoidea is 139, of which 19 came from 9 outcrops and 120 from cores of 37 boreholes. The described samples represent 3 orders, 1 superfamily, 8 families, 2 subfamilies, 16 genera, 20 species (9 new), and 1 new subspecies. The authors consider that all the remains belong to fossil cnidarians. Fossil cnidarians are especially important from a facial point of view. The remains primarily indicate normal sea conditions in warm subtropical and tropical zones. In some cases, the identification of fossil cnidarians is easy, but usually we need to use the oriented thin sections. In the paper, only a small part of the collection is described following the system of Heliolitoidea developed by Olga Bondarenko. A studied collection is deposited in the Geological Department of the National Museum of Natural History, NAS of Ukraine under the number GD-1986.

Identify Landslide Precursors from Time Series InSAR Results

Landslides cause huge human and economic losses globally. Detecting landslide precursors is crucial for disaster prevention. The small baseline subset interferometric synthetic-aperture radar (SBAS-InSAR) has been a popular method for detecting landslide precursors. However, non-monotonic displacements in SBAS-InSAR results are pervasive, making it challenging to single out true landslide signals. By exploiting time series displacements derived by SBAS-InSAR, we proposed a method to identify moving landslides. The method calculates two indices (global/local change index) to rank monotonicity of the time series from the derived displacements. Using two thresholds of the proposed indices, more than 96% of background noises in displacement results can be removed. We also found that landslides on the east and west slopes are easier to detect than other slope aspects for the Sentinel-1 images. By repressing background noises, this method can serve as a convenient tool to detect landslide precursors in mountainous areas.

Exceptional variability in historical fire regimes across a western Cascades landscape, Oregon, USA

AbstractDetailed information about the historical range of variability in wildfire activity informs adaptation to future climate and disturbance regimes. Here, we describe one of the first annually resolved reconstructions of historical (1500–1900 ce) fire occurrence in coast Douglas‐fir dominated forests of the west slope of the Cascade Range in western Oregon. Mean fire return intervals (MFRIs) across 16 sites within our study area ranged from 6 to 165 years. Variability in MFRIs was strongly associated with average maximum summer vapor pressure deficit. Fire occurred infrequently in Douglas‐fir forest stands seral to mountain hemlock or silver fir, but fire frequency was much shorter than predicted by theory in other forest types. MFRIs within Douglas‐fir stands seral to western hemlock or grand fir ranged from 19 to 45 years, and MFRIs in stands seral to Douglas‐fir ranged from 6 to 11 years. There was little synchrony in fire occurrence or tree establishment across 16 sites separated by 4 km. The lack of synchrony in fire suggests that large, wind‐driven fire events that are often considered to be characteristic of coast Douglas‐fir forests were not an important driver of succession in our study area during the last ~400–500 years. Climate was more arid than normal during fire years in most forest types, but historical fire in stands seral to Douglas‐fir was strongly associated with antecedent moisture and less strongly associated with drought. We interpret the extraordinary tempo of fire we observed in stands seral to Douglas‐fir and the unique climate pattern associated with fire in these stands to be indicative of Indigenous fire stewardship. This study provides evidence of far more frequent historical fire in coast Douglas‐fir forests than assumed by managers or scientists—including some of the most frequent fire return intervals documented in the Pacific Northwest. We recommend additional research across the western Cascades to create a comprehensive account of historical fire in highly productive forests with significant cultural, economic, and ecological importance.

Temporal trends in reptile occurrence among temperate old-growth, regrowth and replanted woodlands.

Reptiles are an important part of the vertebrate fauna in the temperate woodlands of south-eastern Australia. However, compared to birds and mammals, the long-term occurrence of reptiles across woodland growth types-old growth, regrowth, and replantings-remains poorly understood. Here, using 18-years of data gathered at 218 sites across 1.5 million hectares in New South Wales South West Slopes bioregion, we sought to quantify patterns of temporal change in reptile occurrence and determine if such changes varied between woodland growth types. Despite extensive sampling, almost 75% of our 6341 surveys produced no detections of reptiles. Significant survey effort exceeding 2000 surveys was needed over a prolonged period of time to record detections of 26 reptile species in our study area. Our analyses showed a temporal increase in estimated reptile species richness and abundance over 18 years. Such increases characterized all three vegetation structural types we surveyed. At the individual species level, we had sufficient data to construct models for five of the 26 species recorded. Three of these species were least commonly detected in replantings, whereas the remaining two were most often detected in replantings relative to old growth and regrowth woodland. We found evidence of a temporal increase in two skink species, a decline in one gecko species, and no change in the remaining two skink species. Although detections were consistently low, active searches were the best survey method, and we suggest using this method in habitats known to be hotspots for reptiles, such as rocky outcrops, if the aim is to maximize the number of individuals and species detected. Our findings highlight the value of all three broad vegetation structure types in contributing to woodland reptile biodiversity.

Glacier changes since the Last Glacial Maximum on two slopes of Mt Noijin Kang‐Sang, Southern Tibetan Plateau

ABSTRACTIn recent decades, most glaciers have been melting, thinning and retreating globally in response to continuously increasing temperatures. We simulated ice thicknesses and volumes on the east and west slopes of Mt Noijin Kang‐Sang, Southern Tibetan Plateau (TP), since the Last Glacial Maximum (LGM), using a glacial flowline model. The simulated average ice thicknesses during the LGM and Lateglacial (LG), Early Holocene, Neoglacial and the Little Ice Age (LIA) periods were 1.4, 1.3, 1.1 and 1.2 times greater than those of modern glaciers in the Gangbu (eastern slope) and western valleys, respectively. In the Gangbu Valley, areas from the LGM‐LG to LIA periods were 1.7, 1.5, 1.4 and 1.2 times greater than the modern glacier area, and the volume expansion indexes were 2.2, 1.9, 1.5 and 1.4. In the western valleys, the area expansion indexes were 2.2, 1.9, 1.5 and 1.4 times greater than the modern glacier, and volumes were 5.4, 4.4, 3.4 and 2.9 times greater, respectively. Glaciers in the western valleys retreated more extensively than those on the eastern slopes of Gangbu Valley after the LGM‐LG, probably due to the smaller glaciers on the leeward western slopes with lower elevations. Equilibrium‐line altitudes dropped ~425 m in Gangbu Valley and ~385 m in the western valleys during the LGM‐LG, corresponding to a 3.8–4.1 °C temperature decrease in this region, which was consistent with cooling on the central Tibetan Plateau, but lower than cooling at the south‐eastern edge of the Tibetan Plateau.

Experimental study on the influence of embankment slope direction on near-surface thermal conditions in permafrost region, Qinghai-Tibet Plateau

Heterogeneous ground thermal conditions caused by slope orientation are significant in Qinghai-Tibet Plateau because of the high altitude and strong solar radiation. Variation in solar radiation may result in contrasting thermal and upper boundary conditions, causing engineering problems at infrastructure with sloped embankments. Quantitative research on conditions on different man-made slopes is insufficient in permafrost regions, and consequently, planning for long-term effects on linear infrastructure is challenging. Net radiation, heat flux, near-surface temperature, soil moisture content, were recorded for one whole year (2021) at a field platform with eight slopes. Slope orientation affected net radiation (Rn) and ground heat flux (G), resulting in different energy balances between slopes. The north facing slope had a lowest Rn (174 W m-2), while the south slope had a maximum (239.8 W m-2). The north slope had a negative annual heat flux (-0.7 W m-2), while a maximum positive flux (1.5 W m-2) was recorded on the southeast slope. The annual mean surface temperature (Ts) was highest on the south slope and lowest on the north slope. The maximum difference of ground temperatures (within 30 cm depth) (Tg), was close to differences in Ts of over 4 °C. The maximum difference in soil moisture content during the thawing season (May–October) was 11% between the W and E slopes. Due to the different ground temperatures and soil moisture conditions, the annual number of freeze-thaw cycles was variable, and the maximum freeze-thaw cycles were 106 times in south slope and the minimum were 18 times in west slope. Those different thermal conditions between different slope orientations were significant, and pertinent to planning and maintenance of infrastructure. The results provide accurate boundary conditions for modeling to support development of new infrastructure that have embankment slopes in any direction, and for ensuring the stability of existing structures on Qinghai-Tibet Plateau.

Fault-related sanctuaries of Mycenae (Greece): The Shaft Grave Circle A

Mycenae, one of the most important cities and sacred sites of antiquity in Greece, was built on a tectonic horst uplifted by active normal faults, and both faults show geologic evidence of recent coseismic slip. The Lion Gate fault, affecting the west slope of Mycenae, is described here through geological and archaeoseismological investigation. The tectonic offset since the Pliocene−Pleistocene sequence is 13−14 m. A 4−5-m-high scarp of the major splay of this fault, well preserved inside the Shaft Grave Circle A, exhibits tectonic geomorphological aspects typical of recent surface faulting. Mycenae experienced two earthquakes in ∼60 yr during its climax, one around 1250 B.C. and the other around 1190 B.C. Seismic damage at Shaft Grave Circle A was found to have occurred on more than one occasion. One event occurred with the earthquake of 1190 B.C., or more likely with a much later one, which cut the circular parapet. Heavy damages were also registered with the earthquake of 1250 B.C. An episode of surface faulting appears to have occurred shortly before the early graves were created in Shaft Grave Circle A (late seventeenth century B.C., Middle/Late Helladic period). The integration of available data suggests that the cults at Mycenae, particularly at Shaft Grave Circle A, deliberately chose specific sites or traits of the seismic fault as the central hub of their main sanctuaries. This occurrence was the result of a deliberate choice dictated by the fact that those sites along the fault trace were considered to be sacred and believed to be gateways to Hades.

Termite diversity and abundance based on altitude in Mount Ungaran, Central Java, Indonesia

Abstract. Subekti N, Milanio RR. 2023. Termite diversity and abundance based on altitude in Mount Ungaran, Central Java, Indonesia. Biodiversitas 24: 3332-3337. Termites are social insects whose main diet is the cellulose and lignocellulose found in rotting wood and in some fungi. As the Mount Ungaran area in Central Java, Indonesia, has been converted to agriculture and other purposes, termite habitat has become increasingly narrow, with a reduction in the insects’ food sources. The purpose of this study was to analyze the species of termites found on Mount Ungaran and the factors that influence their lives. In addition, the differences in species according to slope (north, south, east, and west) and altitude were assessed. This research was conducted in three stages: termite collection, termite identification, and data analysis. The main species found in this study were Coptotermes curvignathus Holmgren, 1913, Odontotermes javanicus Holmgren, 1912, Macrotermes gilvus Hagen, 1858, Nasutitermes matangensis Haviland, 1898, and Bulbitermes constrictiformis Holmgren, 1914. Based on a Shannon-Wiener analysis, the west slope had the highest diversity index, which was primarily influenced by four environmental factors (soil pH, soil temperature, soil moisture, and rainfall). In the canonical relationship correspondence analysis, soil pH, light intensity, and canopy cover were the environmental factors that most affected the diversity and abundance of termites on Mount Ungaran. The conclusions that can be drawn from this study are that termite richness varied between slopes and the environmental factors that were the most associated with the variation were soil pH, light intensity, and canopy cover.

Analysis of mooring-observed bottom current on the northern continental shelf of the South China Sea

The bottom current is an important component of the three-dimensional ocean circulation, which is of significance for the safeties of ocean bottom engineering and facilities, the research on sediment and pollutant transports, and the ecological environment. Due to the lack of observation data, research on the bottom current in the South China Sea (SCS) has been limited. This study systematically analyzes bottom currents from 0.5 to 5 m above the seafloor based on 20-month-long mooring observations on the shelf slope west of the Dongsha Atoll. The spectral analysis results indicate that currents induced by the internal tides and the internal solitary waves (ISWs) comprise dominant constituents of bottom currents with velocity amplitudes up to O(50–90) cm/s. Dominant internal tide-induced bottom currents of the velocity amplitude of O(50) cm/s occupy 53% of the total horizontal kinetic energy. The pulsating ISW-induced bottom currents reach a maximum amplitude of 93 cm/s, which has intrinsic relation to the amplitude of the ISWs, according to the soliton propagation speed solutions of the Korteweg–De Vries (KdV) equation. The background bottom current is strongest in winter, followed by spring, and weak in summer and autumn, which is closely correlated with the behavior of mesoscale eddies. These results are of significance for understanding the dynamics of the bottom boundary layer.

Potato cultivation on the west slope of Mount Slamet: millennial farmers perceptions and intentions for conservation-based farming

A comprehension on the millennial farmers’ perceptions about land degradation, and their intentions to perform conservation-based farming is the initial effort in formulating appropriate programs and policies to control land degradation on the Mount Slamet’s western slope, Central Java. This study aims to: 1) explore the perceptions of millennial farmers about land degradation in potato farming and 2) discover the effect of these perceptions on their intention to do pro-environmental farming. The research was conducted in Paguyangan Brebes from January to March 2022 with a total sample of 189 millennial farmers aged 19-39 years. Research data were collected using a questionnaire with a Likert scale of 1-5. The analysis used was descriptive analysis and SEM-PLS through WarpPLS 7.0 software. The results showed that 96.83% of the millennial farmers realized that there had been a phenomenon of land degradation for potato cultivation. The decline in potato production is the strongest indicator of millennial farmers’ perceptions of land degradation conditions (LC) and land degradation risk (RISK). Both are the antecedents of millennial farmers’ intention to perform conservation-based farming (INT) partially. RISK acted as a mediating variable between LC and INT. INT reinforcement can be sought by clarifying the understanding of millennial farmers about the risk of land degradation in potato farming.

Geochemical characteristics of source rocks and gas exploration direction in Shawan Sag, Junggar Basin, China

In recent years, significant advancements have been achieved in the exploration of natural gas around Shawan Sag in the Junggar Basin. However, the geochemical characteristics and distribution of source rocks in the center of the sag have yet to be thoroughly researched, and there is a lack of understanding regarding the evolution history of hydrocarbon generation and the characteristics of each set of source rocks. This has posed limitations on future exploration and development initiatives in the area. The study focused on source rock samples from the uplift zone and conducted a comprehensive evaluation through seismic and hydrocarbon generation thermal simulation experiments. This allowed for clarification of the product characteristics of source rocks in different strata and pointing out the direction for future natural gas exploration. The results showed the presence of four sets of well-developed source rocks in Shawan Sag, characterized by their extensive thickness, wide distribution, and deep burial, laying a material foundation for oil and gas accumulation in peripheral structures. The Carboniferous and Jiamuhe Formation source rocks have high organic matter abundance, but the quality is poor and the potential for generating hydrocarbons is low, leading mainly to the generation of dry gas. On the other hand, the Fengcheng Formation and Lower Wuerhe Formation source rocks have high organic matter abundance and good quality, and are highly mature, resulting in high potential for generating hydrocarbons. The δ13C1-RO regression equation of natural gas in Shawan Sag was established, and the carbon isotope distribution patterns of ethane generated from source rocks in different layers were identified, providing a foundation for determining the maturity of natural gas and correlating the sources of gas in surrounding structures. The west slope of Shawan Sag has favorable preservation conditions and is located on a hydrocarbon migration pathway, similar to the slope of Mahu Sag. This area also has favorable geological conditions for the formation of large lithologic reservoirs, making it a key field for gas exploration in the study area moving forward.

The Application of Stochastic Seismic Inversion Method of Geostatistical Inversion in Putaohua X Area

Stochastic seismic inversion is an important part of geostatistical inversion method, and is the combination of seismic inversion and sequence simulation. In the process of random seismic inversion, firstly, the histogram distribution of random variables is counted, the variation function of random variables is calculated, and the variation range of random variables in different directions is determined. Then, for each implementation, the seismic traces are synthesized at the seismic channel position according to the calculated reflection coefficient, and the error between the synthetic traces and the original seismic traces is compared, and the inversion results are output after the required accuracy is reached. Geostatistical inversion can improve the vertical and horizontal resolution of the reservoir and accurately describe the spatial distribution of the reservoir. Taking the Heidimiao oil layer in the west slope area of Daqing Placanticline as an example, this paper expounds the application of geostatistical inversion in the work area as a whole. Combined with the results of seismic attribute analysis and well logging curve preprocessing, the inversion results formed by accurate time-depth calibration and other processes of reservoir sensitivity parameter analysis provide a basis for optimizing the target well location in the work area.

Identification of favorable underwater reservoirs in a conglomerate fan delta

Conglomerates are the main components of fan delta-front and usually the important reservoirs in an oilfield, but the cyclicities of the conglomerate deposition readily lead to stratigraphic multiplicities. Therefore, the accurate prediction of the distribution patterns and scales of the conglomerate fan delta has great significances for the oil and gas exploration and production. The conglomerate fan delta of the Triassic Baikouquan Formation (TBF) in the west slope of the Mahu Sag, Junggar Basin is a research hotspot because billions of petroleum resources have been discovered in this Formation. However, the stratigraphic correlation of the conglomerate of the TBF is still unclear for the particularly heterogeneous of the conglomerate strata, which caused the paleogeomorphology and favorable underwater reservoirs of the TBF are yet to be determined. In this study, the integrated methods of seismic interpretation, well logging, well curves and heavy minerals are applied to study the paleocurrent directions, ancient trench distribution and shoreline positions of the lake. The results show: (1) There are two ancient trenches developed in the west slope of the Mahu Sag. (2) The shoreline positions are generally distributed along the shape of ancient trenches. And (3) the favorable underwater reservoirs in a conglomerate fan delta are distributed in the front of the shoreline as a progradation deposits of the fan delta. The lake level elevation and paleotopography jointly controlled the lithology and reservoir physical properties, and the underwater facies belt in the ancient trench are the favorable exploration zones.

Unguentaria in pre-Roman Dacia. Finds from Cetăţeni

Various products from Asia Minor and Pontus reached the Geto-Dacian settlements north of the Lower Danube mainly from the 2nd century BC until the very beginning of the 2nd century AD. They are reflected in the archaeological discoveries especially through pottery (West Slope, Hadra/Lagynoi wares, Megarian Bowls, Appliqué wares, Lead Glazed ware, grey ware, Pergamene Sigillata, Eastern Sigillata B and Pontic Sigillata); amphorae from Rhodes, Thasos, Cnidus, Kos, Sinope, Heraclea Pontica, or Chersonesus; Pergamenian and Ephesian lamps and glass vessels made by various techniques (core made, mould or free blown, sagging, cut-faceted or splashed made). Following the excavations conducted between 2002-2004 in the Late Iron Age settlement at Cetăţeni (Argeș County, Romania), a pit containing autochthonous handmade and wheel thrown pottery, fragments of amphorae, a cylindrical glass bead and also an unguentarium fragment were discovered. From the chronological point of view of this sealed archaeological context is of great relevance for the settlement. The discovery allows us to make some observations concerning import and use of perfumes and aromatic oils north of the Lower Danube, in the Barbaricum, before the making of the new Roman province of Dacia.