North Caspian Research Articles

Weight change and incident metabolic syndrome in Iranian men and women; a 3 year follow-up study

BackgroundAlthough the association of weight gain and developing metabolic syndrome (MetS) has been reported in the Western and Asian populations, data on the gender-stratified effects of weight change (including weight loss) on incident MetS and its components in the Middle East Caucasians is still scarce.MethodsA total of 1431 men and 2036 women aged ≥ 20 years with BMI > 18.5 kg/m2 were followed over 3 years. Multivariate logistic regression analysis was used to estimate the relative risk (RR) of MetS and its components (the Adult Treatment Panel III definition) associated with gender-stratified quintiles of percent weight change. Subjects with MetS at baseline were excluded for analyzing the RR of MetS.ResultsThere was 20.4% (95% CI, 19.6–21.2) age-adjusted incident MetS (18.4% male vs. 23.1% women). In men, mild weight gain (WG) predicted high waist circumference (WC) and high triglyceride; moderate WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high blood pressure (BP); large WG predicted MetS (RR 3.2, 95% CI 1.8–5.7) and its components, except for high fasting plasma glucose. In women, mild WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high BP; moderate WG predicted Mets (RR 4.6, 95% CI 2.7–8.0), high WC and high triglyceride; large WG predicted MetS (RR 6.6, 95% CI 3.8–11.3) and its components except for low HDL-cholesterol. Mild weight loss had protective effect on high WC in both genders and MetS in men (RR 0.5, 95% CI 0.26–0.97, P = 0.04).ConclusionWeight change showed different effects on MetS in men and women. In women, mild WG predicted MetS; however, mild weight loss was protective against MetS in men and high WC in both genders.

On strategy of the upcoming exploration phase in the North Caspian petroleum province

This paper gives a review of oil and gas resource potential of the North Caspian petroleum province. A new potential for finding several giants and large-size discoveries exists, respectively, in the presalt and postsalt sequences. Recommendations for future directions in exploration targeting at postsalt deposits (Upper Permian–Triassic and Jurassic–Paleogene petroleum systems) are given. It is emphasized that, given adequate exploration techniques, the postsalt sequence may provide stable and commercial production for decades. Most of the prospects are located within nonlicensed area. Therefore, the future exploration activity will have to be implemented through special-purpose governmental projects, namely, state-funded integrated projects aiming at investigation of the individual petroleum regions and zones.

Participles and Finiteness: The Case of Akhvakh

In Akhvakh, a Nakh-Daghestanian language belonging to the Andic branch of the AvarAndic-Tsezic family , dependent clauses may involve subordination mechanisms of types commonly applied to clauses headed by independent verb forms, or the use of strictly dependent verb forms (infinitive and converbs). But Akhvakh also has verb forms that question the notion of finiteness by being used both as heads of typical participial relative clauses, and as independent verb forms. On the other hand, there is no correlation between the morphological characteristics of Akhvakh verb forms (in particular with respect to argument indexation) and their ability to head independent clauses. In order to eliminate the inconsistencies following from the use of current terminology in the description of Akhvakh verb inflection, the idea of a necessary correlation between the morphological characteristics and the syntactic abilities of verb forms must be abandoned, and the definition of the type participle must be reformulated in a way making it logically independent from the type non-finite verb form. This means that the negative conditions implied by the notion of non finiteness as it is currently understood must be eliminated from the definition of participle, and participles must be defined exclusively with reference to their ability to occur in constructions constituting a particular type of relativization strategy, in which they behave at the same time as verbal heads and as adjectival dependents of a head noun.

The Spread of the Neolithic in the South East European Plain: Radiocarbon Chronology, Subsistence, and Environment

Newly available radiocarbon dates show the early signs of pottery-making in the North Caspian area, the Middle-Lower Volga, and the Lower Don at 8–7 kyr cal BC. Stable settlements, as indicated by “coeval subsamples,” are recognized in the Middle-Lower Volga (Yelshanian) at 6.8 kyr cal BC and the Caspian Lowland at about 6 kyr cal BC. The ages of the Strumel-Gostyatin, Surskian, and Bug-Dniesterian sites are in the range of 6.6–4.5 kyr BC, overlapping with early farming entities (Starčevo-Körös-Criş and Linear Pottery), whose influence is perceptible in archaeological materials. Likewise, the14C-dated pollen data show that the spread of early pottery-making coincided with increased precipitation throughout the forest-steppe area.

NEW DATA ON RADIOCARBON CHRONOLOGY OF NEOLITHIC CERAMICS FROM THE VOLGA-KAMA REGION

The present article outlays a chronological sequence based on radiocarbon dating using ceramics from Neolithic sites in the Volga-Kama region. Sites in the North Caspian region are considered the most ancient being dated to the first half of the 6th millennium BC. The Neolithic culture of the southern forest-steppe zone of the Volga-Ural interfluve was formed at approximately the same time. Neolithic sites in the Lower Volga region are considered slightly later dating to the second half of the 6th millennium BC. Contacts between the steppe and forest-steppe cultures of the Middle Volga led to the emergence of the pricked decorative style in ceramics in the early 5th millennium BC. This tradition survived until the early 4th millennium BC. In the mid 5th millennium BC, the comb-cogged stamp decorative element emerged in the forest-steppe zone of the eastern Volga and in the forest zone of the Volga-Kama region. In southern areas, this tradition continued until the mid 4th millennium BC, and in northern areas, until the late 4th millennium BC.

Person variations in Akhvakh verb morphology: functional motivation and origin of an uncommon pattern

Abstract In the Nakh-Daghestanian language family, person agreement is considered a recent innovation of a few isolated languages. Person variations in Akhvakh verb morphology are limited to the perfective positive and follow a typologically rare pattern, in which the same couple of verbal endings encodes a 1st person vs. 2nd/3rd person contrast in declarative clauses, and a 2nd person vs. 1st/3rd person contrast in questions. A comparison of the verb forms concerned by this distinction with other Akhvakh verb forms not involved in this mechanism suggests that, in Akhvakh, the emergence of this atypical pattern resulted from the reanalysis of a TAM distinction.

Spatial and temporal distribution of macronutrients and phytoplankton before and after the invasion of the ctenophore, Mnemiopsis leidyi, in the Southern Caspian Sea

The spatio-temporal distribution of nutrients and phytoplankton along the Iranian coast of the Southern Caspian Sea (CS) was investigated by comparing two different periods, namely Phase I (1996–1997), representing the period before the introduction of the ctenophore, Mnemiopsis leidyi, into the system, and Phase II (2005), the period after the introduction. The results showed that nutrient concentrations (with the exception of dissolved silicate) in the subsurface water were significantly higher during Phase II (p<0.001), which may be attributed to vertical mixing and the presence of the ctenophores. Long-term data collected from 1994 to 2005 also confirmed these results. As with most other marine ecosystems, the Bacillariophyta (diatoms) was found to be the most dominant phytoplankton group. However, during Phase II (i.e. after the introduction of the ctenophores), a significant increase in the abundance of the Cyanophyta was recorded, especially during summer and autumn. The average abundance of phytoplankton after the introduction of the ctenophores was significantly higher (4.2 fold, p<0.05). Similar trends have been observed in the Narragansett Bay and in the Black, Azov and North Caspian Seas, all of which were related to the predation on zooplankton (the primary consumer of the phytoplankton) by the ctenophores.

Geological evolution and petroleum systems in the North Caspian Region

The structure and formation evolution of the principal North Caspian zones (North Caspian Basin, Karakul-Smushkovskii Foredeep, South Emba Foredeep, Karpinsky Range Fold Zone, Mangyshlak-Central Ustyurt Fold Zone, etc.) are discussed. Drilling data and seismic profiles were utilized in the study, and an analysis of hydrocarbon systems has been performed.

Modern state of soil salinity in solonetzic soil complexes at the Dzhanybek Research Station in the North Caspian Region

Variations in the salinity of virgin soils of solonetzic soil complexes at the Dzhanybek Research Station are characterized on the basis of field materials obtained by the author in 2002–2004. The soil salinity is characterized with respect to the depth of the upper boundary of salt-bearing horizons, the total amount of salts, the content of toxic salts, and the chemical composition of salts. Changes in the soil salinity under dry farming conditions are estimated for the following soil management practices: (1) agroforest amelioration with additional moistening of virgin soils owing to snow retention by the adjacent shelterbelts and forest plantations, (2) intense grazing, (3) soil fallowing after normal tillage to a depth of 20–25 cm, and (4) soil fallowing after deep tillage to a depth of 40–50 cm. It is shown that normal tillage and considerable grazing pressure do not affect the salinity of the studied soils. No definite effect of the shelterbelts on the salt status of the adjacent virgin soils of the solonetzic complex has been revealed. Deep soil tillage strongly affects the salt status of solonetzes: the content of toxic salts in the upper meter considerably decreases. Virgin solonetzes are usually moderately or strongly saline soils, whereas deeply tilled solonetzes are slightly or moderately saline soils.

Extrusion tectonics and subduction in the eastern South Caspian region since 10 Ma

We examine active deformation of the region surrounding the eastern South Caspian Sea using a combination of seismic, geological, geodetic, and geomorphological data. Global positioning system (GPS) velocities indicate a westward component of motion of the South Caspian basin, relative to Eurasia and central Iran. We identify major zones of shear (the Ashkabad and Shahrud fault zones) that accommodate this westward extrusion on either side of the South Caspian block. Estimates of total strike-slip motion could, at present-day slip rates derived from GPS observations, be achieved in ~10 m.y. Therefore, the northwest extrusion of the South Caspian region, which is accommodated by subduction beneath the North Caspian region (stable Eurasia) along the Apsheron-Balkan sill, may also date from that time. This suggests that the onset of subduction may be older than previous estimates (ranging from 1.8 to 5.5 Ma). Our results are summarized in a new kinematic model that significantly clarifies the active tectonics of this complicated region.

Subsurface seepage of seawater across a barrier: A source of water and salt to peripheral salt basins

Many of the great Phanerozoic salt basins share a common paleogeography, in which a deep lake or sea is separated from the ocean by a narrow barrier. Examples include the Aptian evaporites of the South Atlantic rift basins and the Messinian salt deposits of the Mediterranean Sea and the North Caspian depression. Marine transgressions over the barrier have been proposed as the origin for saline conditions in these basins. We test an alternate hypothesis, that subsurface seepage of seawater through the barrier was a significant source of water, influencing both water level and water composition. Our model permits flux of water and salt into and out of the basin via (1) seepage through the barrier; (2) evaporation from the water surface; (3) rainfall and/or rivers; and (4) incorporation into basin sediments. Our investigation focuses on three settings, a modern analog in the Gregory Rift of northern Kenya, the Messinian Mediterranean basin, and the Early Cretaceous Aptian salt basins of the South Atlantic. We test our model through a numerical simulation, applying reasonable values for the dimensions of the barrier, differences in water level, and hydraulic conductivities to calculate flow rates through the barrier. Modeling results indicate that flux of seawater through a barrier to a peripheral basin ranges from the dominant component of lake water to insignificant, depending on the climate, size of the peripheral basin, and hydraulic conductivity of the barrier. The flux of salt is significant over the full range of modeled hydraulic conductivities, producing brines in the peripheral lake and/or sea within 0.5 m.y. in most cases. This demonstrates that seepage through the barrier can account for lithologic and organic geochemical evidence for saline water conditions, and that marine transgressions across the barrier are not necessary to explain the apparent high salinities.

Age of Khvalynian transgressions in the Caspian Sea region

As follows from a geomorphologic analysis of the Khvalynian sediments in the North Caspian region, radiocarbon dating of their molluskan and plant remains provided more or less reliable age estimates, according to which the Khvalynian transgression occurred approximately 11-20 ka B.P. This value corre- sponds, however, to the terminal transgressive-regressive phase of the latter, i.e., rather to the Late Khalynian transgression than to its Early Khvalynian peak. It is inferred that the high terraces that formed during the max- imal Early Khvalynian transgression are unambiguously older, being 70 to 40 ka in age.

Nature of the North Caspian gravity anomaly

With the use of the method of complete geological reduction, it has been shown that the unique gravity anomaly that frames the Near-Caspian petroliferous basin in the south is related to the Lower Paleozoic volcanic-terrigenous complex that occurs at the base of sedimentary cover at a depth of 8–12 km. This complex was formed contemporaneously with spreading of the Ural-Turkistan ocean and mark a rift zone in the south of passive margin of the East European continent. The rift was conjugated with an ancient triple junction on the floor of the Ural-Turkistan paleocean.

カスピ海周辺プロジェクトにおける環境への取り組み―ＩＮＰＥＸ関連プロジェクトを例として―

Caspian Sea is the largest inland body of water on earth which surrounded by Azerbaijan, Iran, Kazakhstan, Russia, and Turkmenistan. Some 130 large and small rivers flow into the Caspian Sea and there is no natural outflow. The coastal wetlands of the Caspian include many shallow, saline pools, which attract a variety of bird life and biodiversity. In addition, the sea's native sturgeon is famous the world around for the roe it produces.INPEX is participating North Caspian Sea Project in Kazakhstan, ACG Project in Azerbaijan and BTC Pipeline Project which starting from Baku, Azerbaijan, via Tbilisi, Georgia, to Ceyhan, Turkey.This presentation shows some examples of practical environmental management in these projects.

Accommodation and Sedimentary Architecture of Isolated Icehouse Carbonate Platforms: Insights from Forward Modeling with CARB3D+

Abstract A fundamental control on the evolution of carbonate platforms is accommodation, the space available for sediment deposition. Here we adopt a sensitivity-analysis approach, using the process-based forward model CARB3D+, to quantitatively investigate the sedimentary response of isolated carbonate platforms to individual accommodation drivers of eustasy, subsidence, and surface dissolution. Sediment production, the mechanism invoked to fill accommodation, is also investigated. Fourth-order Milankovich-driven sea-level cycles dominate icehouse carbonate sedimentology, with 400 ky cycles modulating the effect of 100 ky cycles of comparable magnitude when both cycles are present. Both overwhelm higher-frequency, lower-amplitude fifth-order cycles, which are rarely preserved on the platform top. Subsidence is a fundamental control on sedimentary stacking patterns, sequence-boundary frequency (SBF), and platform geometry, with rapid subsidence increasing the preservation of platform-top sequences. Most icehouse platforms are subject to extended periods of platform-top exposure. Missed beats, when the platform top remains emergent at a sea-level maximum, are common and create non-Milankovich SBFs. Furthermore, during platform emergence, surface lowering via surface dissolution also creates accommodation for the subsequent platform flooding event, with surface dissolution rates in humid climates comparable to moderate rates of subsidence. However, accommodation generation by surface dissolution is self-limiting, in as much as accommodation generated by dissolution is rapidly refilled on flooding. Sediment production is a key control on unfilled accommodation, which our simulations suggest is considerable on icehouse platforms. Increased shallow-water (< 3 m depth) sediment production enhances intra-platform bathymetric relief between the margin and interior; this is driven in large part by a higher sedimentation rate at the margin than in the interior. Platforms can be flooded to depths up to 45 m during marine transgressions, and accommodation often remains unfilled. There are two distinct phases of platform-top sedimentation. During the transgression and early highstand, platform margins accumulate at a greater rate than interior sediments, generating differential intra-platform bathymetry. Subsequently, accommodation in the interior fills by forced regression and progradation from the margins into the platform interior. Numerical forward models can augment our understanding of icehouse carbonate-platform evolution by identifying the nature of the sedimentary response to individual controls. They can thus contribute to improving characterization of carbonate reservoirs in icehouse platforms, such as the large hydrocarbon fields in the North Caspian and S.E. Asia.

Reactive polar precipitation via ether cross-linkage: A new mechanism for solid bitumen formation

Analysis of solid bitumens from the Tengiz Field, Kazakhstan by X-ray photoelectron spectroscopy provides evidence for a new reservoir alteration process – reactive polar precipitation via the formation of ether cross-linkages. Solid bitumens, which may occupy >30% of the pore space, were analyzed in situ and as isolated concentrates of the material in vein/fracture-fills or encapsulated within micropores. Their compositions were found to vary greatly, particularly in the amounts of aromatic carbon and in the organic oxygen mostly present in C–O single bond environments. While most solid bitumen in Tengiz reservoir rocks arose from asphaltene precipitates, surfaces are coated with a relatively aliphatic- and oxygen-rich material. Organic sulfur occurs exclusively in aromatic sulfur environments in most samples, while nitrogen is in pyrrolic and pyridinic environments. To account for the average organic composition of solid bitumen, we propose that the coatings are formed by condensation of low-molecular weight polar compounds that are normally soluble in most oils. A likely reaction mechanism involves free radicals, produced by thermally labile non-aromatic sulfur (–SH) forms, reacting with hydroxyls. This reaction results in a release of H 2S and the formation of compounds with at least one ether-linkage and multiple heteroatoms within the aromatic cores. Similar reactions are believed to convert the reactive polar precipitate and previously precipitated asphaltenes into toluene-insoluble bitumens. This hypothesis explains the chemical nature of the solid bitumens, accounts for previously reported anomalies in reflectance, and is fully consistent with current geohistory models. Whether this reservoir alteration process occurs outside of the North Caspian Basin is not known, but we suspect that the process occurs elsewhere. Thin coatings of polar precipitates, which may be undetectable by conventional optical microscopy, could have significant impact on reservoir properties, such as surface wetability or mineral diagenesis.

The Indigenous Languages of the Caucasus, Volume 3: The North East Caucasian Languages, Part 1

The Indigenous Languages of the Caucasus, Volume 3: The North East Caucasian Languages, Part 1

Steep microbial boundstone-dominated platform margins—examples and implications

Seaward progradation of several kilometers has been documented mostly for leeward margin low-angle carbonate slope systems with a dominant platform top sediment source. However, steep and high-relief margins fronting deep basins can also prograde and as such are somewhat perplexing. Characteristics of two prograding Carboniferous examples provide a model which may apply elsewhere: (1) outcrops in Asturias, northern Spain serve as important analogs for (2) hydrocarbon reservoirs in steep-sided isolated platforms of the North Caspian Basin, Kazakhstan, such as Tengiz. Seismic and well data from Tengiz corroborate outcrop patterns for slope development, showing progradation of up to 5 and more than 10 km, respectively, despite the high-relief (up to 600 m) and steep (∼20–35°) nature of these margins. The two examples share a highly productive microbial boundstone factory extending from the platform break down the slope to nearly 300 m (or more) depth and a lower slope dominated by (mega)breccias and grain flow deposits derived from the margin and slope itself. The broad depth range of microbial boundstone increases the potential for production during both lowstands and high stands of sea level and thereby facilitates progradation independent from platform-top-derived sediment. Rapid in situ lithification of the boundstone provides stability to the steep slopes, but also leads to readjustment through shearing and avalanching. What controls the microbial cement boundstone formation remains a debate but its presence is a key factor controlling the progradational geometry of these and possibly other margins. This new model of “slope” shedding has implications for slope readjustment processes and resulting architecture, sequence stratigraphic interpretation, reservoir characterization, and reservoir modeling. Especially the isotropic character of microbial boundstone will reduce the potential for coherent seismic reflections to develop and possibly invoke, under certain stress regimes, shattering and fracturing thereby generating significant non-matrix permeability. Key considerations are the contrasts with the Bahamian high stand shedding depositional model, slope progradation rates that range from 450 to >1500 m/My, and net growth rates of in situ boundstone of ∼1000 m/My, comparable to or higher than accretion rates for metazoan skeletal reef growth.

CANNING BASIN AND GLOBAL PALAEOZOIC PETROLEUM SYSTEMS—A REVIEW

There are more than 131 giant and super-giant oil and gas fields with Palaeozoic source and reservoir that are similar to the Canning Basin. These include Palaeozoic basins of North America, North Africa, and the North Caspian Basin of Kazakhstan and Russia.The productivity of these Palaeozoic petroleum systems depends on timing of generation and preservation of charge. Thick Ordovician, Permian, and Triassic evaporite deposits played a very important role in creating and preserving the North American, north Caspian, and north African giant oil and gas fields, respectively.The Mesozoic–Tertiary charged Palaeozoic systems are typically more productive than the Palaeozoic charged systems as exemplified by the north African basins.The Ordovician sourced and reservoired giant oil fields of the North American Mid-Continent are also highly productive. Within the Canning Basin, Ordovician sourced oil has been recovered on the Barbwire Terrace (in Dodonea–1, Percival–1 and Solanum–1) on the Dampier Terrace (in Edgar Range–1 and Pictor–1) and along the Admiral Bay Fault Zone (in Cudalgarra–1, Great Sandy–1, and Leo–1).The Canning Basin may be the least explored of the known Palaeozoic basins with proven petroleum systems. The Palaeozoic basins of North America are the most explored with 500-wells/10,000 km2 compared to the Canning Basin with only 4-wells/10,000 km2.The presence of five oil fields, numerous oil and gas shows and the well density in the Canning Basin (200 wells in 530,000 km2) suggests that further exploration is warranted. Critical analysis of the distribution of source rock, reservoir, seal, timing of generation versus trap formation and post accumulation modification for each tectonic unit of the Canning Basin is required.

North Caspian Project: Challenges and Successes

This article, written by Technology Editor Dennis Denney, contains highlights of paper SPE 86685, "North Caspian Project: Challenges and Successes," by Lyazzat Sarybekova, Agip Kazakhstan North Caspian Operating Co. N.V., prepared for the 2004 SPE International Conference on Health, Safety, and Environment in Oil and Gas Exploration and Production, Calgary, 29-31 March.