A Workflow to Derive Rock Mechanics Correlations and Stress Profile by the Integration of Dynamic and Static Formation Evaluation Data

Rock mechanics utilizes empirical formulas which are based on studies of certain environments. The shortcoming of such criteria is having estimations of rock physical properties with high uncertainty and not field/formation specific. The objective of this paper is to apply a core-log integration to convert dynamic mechanical properties captured from formation evaluation logs and calibrate them with core static data to generate a continuous profile of data with low uncertainty and generate correlations applicable to the specific physical environment. To obtain proper rock mechanical correlations, building a mechanical earth model (MEM) calibrated with core data and stimulation data is essential. Multiple wells drilled in a certain sandstone field with rock mechanical physical tests are analyzed. Multi-arm caliber data is also put in use to establish knowledge about in-situ stress directions. The procedure starts with gathering and filtering acoustic slowness & shear, formation pressure, density, and oriented multi-arm caliper logs. Next, calibration of dynamic to core static mechanical data collected in the lab is established. The geomechanical analysis includes an understanding of the state of stresses in a chosen reservoir along with rock elastic and failure properties. The complied data is then integrated using different workflows to develop Mechanical Earth Model (MEM). The intended rock mechanics correlations include elastic constants (Young's Modulus and Poisson's ratio), and rock failure parameters. Once Mechanical Earth Model (MEM) is established, dynamic logging data and core static data are correlated to produce key rock mechanics elements that are field and formation specific. The correlations include Young's Modulus, Poisson's Ratio, Unconfined Compressive Strength (UCS) correlation, and Friction Angle (FANG) correlation. A range of each rock mechanic element is also highlighted for the specific environment showcasing the limits expected for collapse and fracture. Ultimately, stress profile is generated with low uncertainty highlighting magnitudes of maximum and minimum horizontal stresses along with the given interval.

Spatial distribution of groundwater recharge, based on regionalized soil moisture models in Wadi Natuf karst aquifers, Palestine

While groundwater recharge is considered fundamental to hydrogeological insights and basin management, only relatively little attention has been paid to its spatial distribution. And in ungauged catchments it has rarely been quantified, especially on the catchment scale. For the first time, this study attempts such analysis, in a previously ungauged basin. Our work based on field data of several soil moisture stations, which represent five geological formations of karst rock in Wadi Natuf, a semi-arid to sub-humid Mediterranean catchment in the occupied Palestinian West Bank. For that purpose, recharge was conceptualized as deep percolation from soil moisture under saturation excess conditions, which had been modelled parsimoniously and separately with different formation-specific recharge rates. For the regionalisation, inductive methods of empirical field-measurements and observations were combined with deductive approaches of extrapolation, following the recommendations for hydrological Prediction in Ungauged Basins (PUB), by the International Association of Hydrological Sciences (IAHS). Our results show an average annual recharge estimation in Wadi Natuf Catchment (103 km2), ranging from 24 to 28 Mm3/yr, equivalent to recharge coefficients (RC) of 39–46 % of average annual precipitation. Thus, for the first time, formation-specific RC-values could be derived, assessed and quantified in their spatial distribution, and by creating a schematic conceptual basin classification framework for regionalisation that is also applicable in many comparable sedimentary basins in the Mediterranean and worldwide.

Temporary Isolation of a Prolific Open Hole Gas Zone using a Non-Damaging Methodology - A Multi-Well Case Study in a Field of Kurdistan N. Iraq

Objectives/Scope A case study is presented detailing the methodology used to place a non-damaging temporary isolation barrier in a group of naturally fractured, prolific gas wells in a field in Kurdistan. The temporary isolation facilitated removal of the original completion string and installation of the redesign. Wells were returned to production with-out the need to stimulate proving success of the non-damaging methodology employed. Methods, Procedures, Process The operator had 4 wells with OH sections ranging from 33-181m which were completed in the 1980’s - 1990's with no production packer. In order to preserve well bore integrity the completion string needed to be pulled and replaced by a string with production packer and DH gauges. A procedure was developed to fill the highly fractured OH with a mixed particle size CaCO3 carried into the wellbore by a non-damaging surfactant based gel. Caliper logs were not available and the presence of natural fractures posed a challenge to calculating the actual OH volume. A system was developed to carry the CaCO3 into the wellbore in stages and slickline was employed to measure fill after each stage. Once the OH was filled with CaCO3 and well would support a fluid column coil tubing was used to place an acid soluble cement plug in the short interval between casing shoe and end of tubing (8-10m) Results, Observations, Conclusions The first well in the campaign required more than 10 times the theoretical volume of CaCO3 to fill the open hole. It was concluded the surfactant gel was likely carrying the CaCO3 into the fractures. The procedure was modified to tie in a line of breaker solution to the well head allowing sufficient viscosity of the fluid to carry the CaCO3 from surface but immediately lose viscosity and allow the CaCO3 to settle in the wellbore without being carried into the formation. Specific coil tubing procedures were employed to allow the setting of ultra-short acid soluble cement plugs (<10m). All wells were successfully isolated to allow the safe workover of the completion string and returned to production with no loss of gas flow, with-out the need to stimulate after the work over. Novel/Additive Information The campaign exhibited a new method of employing existing technologies to achieve the objective in a highly challenging and relatively new oilfield of Kurdistan. The campaign also demonstrated the benefit of the operator and service company closely collaborating on each step of a novel process. The workovers would not have been successful with-out the close collaboration of the two companies.

Field-based estimation and modelling of distributed groundwater recharge in a Mediterranean karst catchment, Wadi Natuf, West Bank

While groundwater recharge is one of the most prominently covered subjects in hydrogeology, the spatial distribution of recharge has been given relatively little attention, especially in semi-arid, karstic aquifers. Under conditions of highly diverse geology, relief, vegetation and land use, the complexity and variability of spatially distributed hydrological processes remains a challenge in many regions around the world. This is particularly true for hitherto ungauged basins, such as Wadi Natuf, a 103 km2 large karstic Eastern Mediterranean watershed in the Palestinian upstream mountain and recharge area of the Western Aquifer Basin (WAB), which is shared with Israel in the coastal plain. In this first in a series of two papers, distributed recharge is estimated and represented, based on 7 years of extensive field observations and measurements and based conceptually on observable physical landscape features such as geology, land use and land cover (LU/LC) and especially soil conditions. For the first time in the WAB, a forward calculated soil moisture and percolation model (SMSP) was set up with parameters directly gained from field observations. The model was parameterised in a strictly parsimonious manner, as a one-dimensional model (a.k.a. “tank”, bucket or box model). This is based on dominant hydrological processes, in particular saturation excess in the soil column, and identifying patterns of linkage between different landscape features. Average soil thickness was encountered at the range of decimetres, rarely above one metre. Both soil thickness and LU/LC features, such as terraced olive groves or forests as well as grassland or barren rock outcrops, were found to be highly formation specific. This linkage allowed us to further simplify the model and its requirements in a realistic manner for eight soil moisture stations, chosen at six different geological formations with typical soil and LU/LC representations. The main result of the model was the determination of formation-specific recharge coefficients, spatially ranging between 0 % and almost 60 % of annual rainfall or up to 300 mm a−1 in Wadi Natuf's climate. The karstified main aquifers showed recharge coefficients (RC) above 40 % and even the less prominent slightly aquitardal local aquifers reached RC values above 30 %. The model was separately tested on two conceptual levels: on the level of basin form (soil moisture) and basin response (signatures of peak recharge and local spring discharge events) under well-controlled conditions in isolated sub-catchments. In principle, our approach is applicable in many of the scarcely gauged karstic groundwater basins around the world with a highly diverse landscape and geology.

Особенности структуры и диэлектрических свойств керамик на основе титаната натрия-висмута

The phase formation, specific features, and the dielectric properties of the ceramics of compositions from the region of morphotropic interface in the (Na_0.5Bi_0.5)TiO_3–BaTiO_3 system modified by Bi(Mg_0.5Ti_0.5)O_3 and also low-melting additions KCl, NaCl–LiF, CuO, and MnO_2 that favor the control of the stoichiometry and the properties of the ceramics have been studied. The ceramics are characterized by ferroelectric phase transitions that are observed as jumps at temperatures near 400 K and maxima at T _m ~ 600 K in the temperature dependences of the dielectric permittivity. The phase transitions at ~400 K demonstrate the relaxor behavior indicating the existence of polar domains in the nonpolar matrix. An increase in the content of Bi(Mg_0.5Ti_0.5)O_3 favor a decrease in the electrical conductivity and dielectric losses of the samples, and the relative dielectric permittivity at room temperature ε_rt is retained quite high, achieving the highest values ε_rt = 1080–1350 in the ceramics modified with KCl.

Schneiderian membrane adult vasculogenesis evaluated by CD31 and CD34 expression and morphological arrangement

Background. Few studies approached the process of blood vessels formation in the Schneiderian membrane. We aimed at investigating by immunohistochemistry the processes that are responsible for forming new blood vessels in the human Schneiderian membrane. Material and methods. We applied CD31 and CD34 markers on bioptic samples gathered from eight adult patients negative for malignant pathologies. Filopodia-projecting endothelial tip cells (ETCs) were found and indicated processes of sprouting angiogenesis. Also, CD31-expressing monocyte-derived cells were found being involved in processes of vasculogenesis. These cells were projecting filopodia, thus being assessed as endothelial progenitor tip cells (EpTCs). Aggregates of CD31+ EpTCs were also analyzed. Further stages of lumen acquisition and large diameter vessels formation, specific for vasculogenesis, were evaluated. Results. It resulted that, specifically within the maxillary sinus mucosa, vascular remodelling is equally ensured by adult vasculogenesis and sprouting angiogenesis. Conclusion. This is, to our knowledge, the first evidence of adult vasculogenesis in the maxillary sinus mucosa, supported by bona fide bone marrow-derived CD31+ cells. The guidance mechanism of EpTCs protrusions needs further investigations for finding similarities, or dissimilarities, with the endothelial tip cells prolongations.

Acute tonsillitis and its complications: an overview

Acute tonsillitis may be defined as inflammation of the tonsils, predominantly due to infection. It is part of the spectrum of pharyngitis, which ranges from localised tonsillar infection to generalised infection of the pharynx and commonly affects young healthy adults. Simple sore throats secondary to viral or bacterial pharyngitis are very common and generally do not require hospital admission or antimicrobial treatment. Supportive management in the form of analgesia and adequate hydration is often sufficient. However, there is potential for life-threatening complications to develop, highlighting the need for basic knowledge in the management of these conditions.This article aims to provide an overview of acute tonsillitis and its complications, including peritonsillar and parapharyngeal abscess formation. Specific attention will be given to the pathogenesis, diagnosis, investigation and management of each condition, in particular advising on emergency pre-shore treatment and indications for referral to an Ear, Nose and Throat Department. We will also summarise important guidelines and evidence from the literature to support these management decisions.

Sense-formation within the future's image distortion as a dialectical relations’ of mutual exclusion dissociation specific for the individuals who suffer from the schizophrenic spectrum disorders

Nowadays schizophrenic spectrum disorders are widely spread. Future's image of the people, whose lives have been impacted by schizophrenia, vastly differs (in comparison with conditionally healthy). Their temporal notions’ formation is based on different laws of thought. Methodological premises for the appearance of this problem could be found in the papers of Aristotle, Kant, Hegel etc.ObjectiveSense-formation within the temporal notions’ formation specific for the individuals who suffer from schizophrenic spectrum disorders.SampleSchizophrenia and schizotypal disorder (ICD-10, F20-21) (40 individuals) and conditionally healthy (40).AimSense-formation within the temporal notions’ formation peculiarities specific for the individuals who suffer from schizophrenic spectrum disorders description.MethodsTemporal Semantic Differential; Autobiographical Method's modification; projective and reflexive techniques.ResultsSense-formation within future's image distortion in a “schisis-typical” way (dialectical relations of mutual exclusion was broken) caused ambivalence in judgments and feelings about their own future (Figure).ConclusionsSense-formation within the future's image distortion in a “schisis-typical” way may cause impossibility of the future's image formation. As a result individuals who suffer from schizophrenic spectrum disorders couldn’t concentrate their attention on their future. This may be the cause of ego centrality specific for the individuals who suffer from schizophrenic spectrum disorders.