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Research indicates that the Jordan River Basin area is an area where serious environmental and cultural changes occur. This paper illustrates a new methodological approach to developing a structural framework to study river basins' cultural and landscape changes. The aim of the proposed framework is to elaborate and overlap the natural and cultural driving forces that influence the landscape and to understand the relationship between them. The study consists of four stages: 1. setting specific objectives coinciding with the study area conditions and specifications; 2. defining a specific technique to determine the selected time frame; 3. defining the factors of each driving force and evaluating their correspondence with the study objectives, and finally; 4. building matrixes of intersections combining the natural force, the cultural force, and the overlapping between both, and adopting specific methodological techniques and tools to measure the outcome of each intersection. The paper presents a case study of the application of the proposed framework in the Jordan River Basin. The research results demonstrate the usefulness of the developed framework in understanding the overlapping between the landscape driving forces (natural and cultural) as well as achieving the goals of the related research. This new approach can facilitate a better understanding of landscape change and help researchers and planners identify and address the key issues related to sustainable landscape management by developing more effective policies and management strategies. [ABSTRACT FROM AUTHOR]

The Red Sea basin is considered one of the world-class examples of continental rifting, breakup and seafloor spreading. This study focuses on the structural framework of the northwestern part of the Egyptian Red Sea margin and the identification of the different rift domains using surface and subsurface data. Subsurface mapping using 2D seismic and borehole data indicates that the northern part of this area represents the continuation of the structural style of the southern Gulf of Suez rift as the mapped structures are mainly down to the northeast main faults with southwest dipping strata. In addition, two negative flower structures have been observed and represent the southern continuation of the Gulf of Aqaba -Dead Sea left-lateral transform fault system. The NE dip of the main rift-parallel faults that characterizes most of the study area flips in the southern part of the area (south of the Duwi accommodation zone) where the fault blocks dip northeastward and the main faults dip SW. Based on the integration of the structural style, continental crust stretching factor (β) and the crustal thickness, the northwestern margin of the Red Sea can be divided into proximal domain, necking domain and potential hyper-extended domain that seems to extend southeast of the area of study and may represent the future locus for oceanic crust development in the northern Red Sea. Each domain is characterized by a distinct structural style and subsidence profiles, and variable preservation and distribution of the pre-rift and syn-rift stratigraphic units. [ABSTRACT FROM AUTHOR]

Considering a cluster of different hierarchical order with various barrier or cadre levels and steps within levels, there is no availability of a structural framework to help exclusively analyze, formulate, identify, differentiate, and design standardized provisional values to cluster members at various barrier levels and steps within levels. This study designs stepwise analysis, generation, and applications of Kifilideen’s Matrix Structural Framework for an infinite term of increasing members of successive levels with the first level having one member of Kifilideen’s Generalized Matrix Progression Sequence. The values of members of the cluster were designed and developed for Kifilideen’s Generalized Matrix Progression Sequence of the infinite term of increasing members of successive levels with the first level having one member and Kifilideen’s Structural Framework was generated for the clusters of such sequence. This Kifilideen’s Matrix Structural Framework also helps to generate Kifilideen’s formulas to identify members and assign values and grades of values to each member within and across levels of Kifilideen’s Matrix Structural Framework. Applications of Kifilideen’s formulas established for Kifilideen’s Generalized Matrix Progression Sequence of the infinite term was carried out. Kifilideen’s Matrix Structural Framework generated some help to exclusively differentiate varying members in the clusters into various levels and steps within levels.

Basic ecological data is mandatory if a forest is to be regulated sustainably. This knowledge is mainly secured via forest inventories. Consequently, our study inventoried the stand structure and soil physicochemical properties in 22 forests across the northern, central, and southern zones of Cross River State using the systematic sampling method. Stand structure was assessed using a Rangefinder and measuring tape at dbh=10 cm and above. An aggregate of 646, 407, and 474 stands were inventoried in the northern, central, and southern zones of Cross River State, respectively. An aggregate of 1527 stands were inventoried in the study area. Using class intervals per zone, stand diameter, and height were used to evaluate the proportion of mature to younger trees. Soil properties were evaluated from ten soil samples collected randomly in each of the surveyed plots in the twenty-two forest areas. We took soil samples with a soil drill at a root depth of 15-50 cm during the rainy season (April - October). Twenty-three soil properties were studied (textural class, soil pH, Organic Carbon, Organic matter, Total Nitrogen, Available Phosphorus, Calcium, Magnesium, Sodium, Potassium, seven trace elements, Electrical conductivity, Exchangeable acidity, Cation exchange capacity, and Base saturation). Results of the stand structure showed that stand diameter class size of 100cm and above had the highest number of stands (19.39%) while the 90-100cm diameter class had the lowest (3.14%). The 10-20m height class had the highest number of stands (56.12%) while the 30m and above class had the lowest (20.37%) in the study area. Soil physicochemical properties revealed the varied presence of the twenty-three soil properties studied across forests. Our findings will provide conservationists, ecologists, and forest managers z with ecological data necessary for sustainable forest management in Cross River State, Nigeria. [ABSTRACT FROM AUTHOR]

Structural analysis of seismic data, combined with well data, provides information for hydrocarbon exploration in a prospective basin. These techniques have been employed in the offshore Lamu Basin to characterize structural and stratigraphic setting of carbonate reefs and assess structural deformation and its effect on trapping mechanisms in the offshore basin. Structural interpretation was based on seismic and well data. A combination of microfossil, nannofossil and palynomorph data provided broad agecontrol for the stratigraphic interpretations. Seismic amplitude brightening attribute was used for tracing structural continuity. Faulted anticlinal traps were formed in the Upper Cretaceous and Tertiary periods. There are inversion features with recent extensional faulting. Favourable structural traps are in the near coastal region. The carbonate reefs in the offshore basin are interpreted from the Early Paleocene to Miocene periods. These reefs formed in the near coastal region, are likely to be quality traps/reservoirs for hydrocarbon accumulation. Five main structures are identified from the depth seismic maps for the Early Paleocene, Late Paleocene and Early Miocene. The reef front may have subsided early, the overlying shales offering the sealing mechanisms. The Davie-Walu transformation was likely to affect the trapping mechanism in the central and southern regions of offshore Lamu Basin. The study provides better understanding of the carbonate reefs' hydrocarbon potential and trapping mechanisms in the offshore basin. [ABSTRACT FROM AUTHOR]

Structural analysis of seismic data, combined with well data, provides information for hydrocarbon exploration in a prospective basin. These techniques have been employed in the offshore Lamu Basin to characterize structural and stratigraphic setting of carbonate reefs and assess structural deformation and its effect on trapping mechanisms in the offshore basin. Structural interpretation was based on seismic and well data. A combination of microfossil, nannofossil and palynomorph data provided broad age-control for the stratigraphic interpretations. Seismic amplitude brightening attribute was used for tracing structural continuity. Faulted anticlinal traps were formed in the Upper Cretaceous and Tertiary periods. There are inversion features with recent extensional faulting. Favourable structural traps are in the near coastal region. The carbonate reefs in the offshore basin are interpreted from the Early Paleocene to Miocene periods. These reefs formed in the near coastal region, are likely to be quality traps/reservoirs for hydrocarbon accumulation. Five main structures are identified from the depth seismic maps for the Early Paleocene, Late Paleocene and Early Miocene. The reef front may have subsided early, the overlying shales offering the sealing mechanisms. The Davie-Walu transformation was likely to affect the trapping mechanism in the central and southern regions of offshore Lamu Basin. The study provides better understanding of the carbonate reefs’ hydrocarbon potential and trapping mechanisms in the offshore basin.

The middle and lower reaches of the Yangtze River is an important iron, copper, gold and other polymetallic metallogenic belt in China. The southern part of the Yangtze River is the southeast Hubei ore concentration area. As an important source of iron and copper deposits in China, several iron-rich copper deposits are concentrated in this area. The Jinniu volcanic basin is located in the southeastern Hubei ore concentration area. The basin has the ore potential of iron, copper, gold and other polymetallic deposits with the similar metallogenic conditions of other mining areas in this metallogenic belt. However, the basin has a thick overlying strata of magnetic rock and sedimentary rock, which increases the difficulty of ore prospecting. Therefore, it is necessary to strengthen the application of technologies for improving the effect of ore prediction. In the adjacent ore concentration areas, the prospecting work mainly focuses on gravity and magnetic data and combined with other geophysical data for comprehensive analysis, which lays a good foundation for the study of structural characteristics and the guidance of prospecting prediction. These previous works has proved that by comprehensive analysis and interpretation of high-precision gravity and magnetic data combined with other geophysical data, the tectonic framework characteristics, buried rocks and physical property distribution of the study area can be extracted, so as to infer the tectonic characteristics of the basin and its basement and put forward prospecting prediction. For the lack of systematic research and demand for prospecting in Jinniu volcanic basin, based on measured and collected geological and geophysical data, comprehensive analysis and interpretation of gravity and magnetic data combined with MT data were carried out. The techniques of linear signal extraction, multi-scale analysis, inversion and resistivity imaging, etc., were utilized to estimate the depth of the basin basement, delineate volcanic mechanism and buried rocks, and speculate fractures, basin boundary, and some areas of prospecting prospect. The such research has the guidance or reference significance for the basic geological survey and deep ore prediction in this area.

• Geophysical and remote sensing studies highlight the basement structural framework. • Crustal fault/shear zones, and belts were induced by subsequent orogenic episodes. • A relationship between mineralization rates and kernel density of lineaments. • Mineral deposits have to be related to deep and brittle-ductile fault/shear zones. • The multi-criteria decision support model highlights hosted mineral potential areas. The Shwas-Tayyah and Khadra belts belonging to the Asir terrane include potential mineralization zones, hosted in intensely deformed Precambrian basement rocks. Analysis of geophysical aeromagnetic data and satellite images, constrained by field data, highlights the deep hierarchy and structuring of the An Nimas-Khadra area in its regional litho-structural setting and geodynamic evolution. The N-S and NNE-SSW major trends, with other E-W, NE-SW and NW-SE minor directions, were identified. The Tarj, Ibran, and Junaynah close to N-S oriented master shear zones, delimit and cross the Al Lith-Bidah, Shwas-Tayyah and Khadra belts; they characterize the Asir composite terrane. Structural and kinematic models were highlighted, showing the control of intense deformations on the basement structures. The deep-seated faults are linked to wide tectonic movements induced by regional E-W to ENE-WSW contractional orogenic episodes. The tectonics induced genesis of the accreted terrane rocks with differentiated belts and shear zones. The resulted structures seem to be in accordance with the Riedel model that includes conjugate movements of right-lateral strike slip faults and right-oblique reverse faults. Correlation of geophysical and geochemical analyses is a crucial technique used for better assessment and valorization of mineral resources. The spatial association between the interpreted lineament patterns and mineralization rates testifies the tectonic deformations-mineral deposits relationship. The AHP-based MCDM statistical support model highlights the mining interest areas. The MCDM allows further spatial statistical evaluation and reveals new prospective metal occurrences in the Shwas-Tayyah and Khadra belts. N-S and NNE-SSW lineament networks show the highest mineralization rates, suggesting their priority for more detailed prospections. The metallic mineral deposits have to be related to prominent steeply dipping and brittle-ductile shear zones. [ABSTRACT FROM AUTHOR]

Urban agriculture is discussed and its examples are implemented in Turkey and in the world due to its depleted resources, access to clean, cheap and safe food, its potential to create open and green spaces, and its contribution to social capital. The importance of urban agriculture, which contributes to economic, environmental and social well-being, has increased even more due to the current COVID-19 pandemic conditions. Urban agriculture is considered as a solution in green-blue infrastructure and nature-based solution applications. Despite the broad context, in this research, the structural and formative processes of urban agriculture in Turkey were evaluated. While discussing the structural context, as the research method, the current legislative structure, plans and policy documents in Turkey were discussed in the context of urban agriculture and the constraints and possibilities in this regard were summarized. The method of the formative context was mentioning the examples of urban agriculture in Turkey and in the world at the neighborhood scale that had been created by NGOs, citizen initiatives and social organizations. The ultimate point reached in the research is that the integration of structural and formative acquisitions is needed to draw the framework of urban agriculture in Turkey. [ABSTRACT FROM AUTHOR]

Abstract There are many factors in a common building project that are not relevant for free-form tall building projects, for example, the free-form planes or various shapes of buildings. Among the many risks present in particular in structural frameworks, the risk of delays is an important one and has a considerable effect on the entire project performance. Generally, a delay causes a decrease in constructability and an increase in cost, so eventually the productibility of the structural framework would decrease. Delay management of structural frameworks in free-form tall buildings is currently performed by project managers based on personal experience and intuition. This nonsystematic management results from the lack of data that are essential for the planning construction process reflected in the particular considerations of the free-form tall building. This study identified the delay factors that can occur in the structural framework of free-form tall building projects and analyzed priorities for delay management. First, the scope of free-form tall buildings was identified, and particular considerations for the structural framework in their construction were determined, such as plane, elevation, floor height, and structure. Delay factors for each category were recognized through interviews with experts with experience in such projects. To prioritize the delay factors, the occurrence and severity of each factor were surveyed. A risk priority number was calculated from the survey results, and the priority was analyzed. The results of this study could serve as preliminary data for the planning construction process of structural frameworks in free-form tall buildings.

The goal of the present paper is presentation of the structural mapping of the karstifid limestones, and the relations between the surface and the underground karstifiation. When mapping on the large scale the frequency of the dip and strike must be increased. Possible intebeds of alien rock must be registered. Measurements of the dip make it possible to ascertain possible plicative deformations. Intercalations of non-carbonate rocks inflence the underground water flw and affect the formation, shaping and location of the karst voids as well as the surface karst features. For the understanding of the karstifiation processes exhaustive collection of structural data, and recognition of broken, crushed and fractured zones within and parallel to fault zones, plus thrust– shear–zones are essential. As spatial organization and dimensions of the underground karst voids, as the surface karst shaping are guided by thrust parallel and fault induced deflction structures. All structural elements, which include tectonic elements as well as bedding planes, lithological changes, lithological partings, less permeable or impermeable interbeds, plus structural elements contribute to the structural framework. It directs both vertical percolation and horizontal streaming within the limestone and inflence the frequency, size, spatial distribution, and shape of interconnected karst voids. The later form the speleogenetic network. Due to the permanent denudation the intersection of the Earth surface and the structural framework and speleogenetic network permanently moves downwards. New structural elements emerge while speleological structures change to less recognizable succession objects. The surface of the karst may be characterized as a dynamic, spatial, hydrogeological and speleological succession system permanently affected by the current tectonic activity.

(Chymo)trypsin-like serine fold proteases belong to the serine/cysteine proteases found in eukaryotes, prokaryotes, and viruses. Their catalytic activity is carried out using a triad of amino acids, a nucleophile, a base, and an acid. For this superfamily of proteases, we propose the existence of a universal 3D structure comprising 11 amino acids near the catalytic nucleophile and base – Nucleophile-Base Catalytic Zone (NBCZone). The comparison of NBCZones among 169 eukaryotic, prokaryotic, and viral (chymo)trypsin-like proteases suggested the existence of 15 distinct groups determined by the combination of amino acids located at two "key" structure-functional positions 54 T and 55 T near the catalytic base His57 T. Most eukaryotic and prokaryotic proteases fell into two major groups, [ST]A and TN. Usually, proteases of [ST]A group contain a disulfide bond between cysteines Cys42 T and Cys58 T of the NBCZone. In contrast, viral proteases were distributed among seven groups, and lack this disulfide bond. Furthermore, only the [ST]A group of eukaryotic proteases contains glycine at position 43 T , which is instrumental for activation of these enzymes. In contrast, due to the side chains of residues at position 43 T prokaryotic and viral proteases do not have the ability to carry out the structural transition of the eukaryotic zymogen-zyme type. [ABSTRACT FROM AUTHOR]

The Penyu Basin is moderately explored but may still have undiscovered hydrocarbon potential for small to moderate size accumulations. Despite the much publicised Rhu-1 oil discovery made in 1991, the Penyu Basin, with only a couple of sub-economic oil discoveries made, has not had much success ever since. This was generally attributed to the poorly developed generative or immature source rocks most likely present in isolated half-grabens within the basin. The Penyu Basin was formed on continental crust, although the exact formation is not properly understood and most authors generally consider it as a pull-apart or "rift-wrench" basin. This is supported by the presence of major strike-slip and associated normal faults being the main basin-bounding faults. The initial half-graben basins developed into isolated lacustrine systems which provide source-rock facies that may have potentially charged traps in the synrift and post-rift sequences. Trap styles identified include compressional anticlines, basement drape structures and synrift stratigraphic/structural traps. Further data acquisition through the last two decades of exploration activities, such as new 3D seismic, geochemical fingerprinting and fluid inclusion investigations, and full tensor gradiometry (FTG) gravity data adding to the past understanding, has enabled a more refined review of the geology and also of the petroleum potential. Undoubtedly, more detailed mapping of new previously undetected structures, coupled with seismic amplitude analyses and advanced quantitative interpretation (QI) techniques may lead to a better understanding of the structural evolution and, hence, to an increase of hydrocarbon prospectivity by identification of additional plays, new leads and to a potential reduction of exploration risk. [ABSTRACT FROM AUTHOR]

• Geochronological data suggested deposition maximum age for the Algodão Formation of 1958 ± 18 Ma. • The youngest zircon was dated as 894 ± 38 Ma in the Serra da Garapa Formation. • Zircon ages in the Santo Onofre Group were similar to glacial units of the Macaúbas Group. The evolutionary history of the Paramirim Aulacogen is characterized by the superposition of rifts that developed from 1770 to 675 Ma. In the Northern Serra do Espinhaço Fold Thrust Belt, two units of this aulacogen were analyzed in the present study: the Algodão Formation (Espinhaço Supergroup) and the Santo Onofre Group (São Francisco Supergroup). In the study area, the Algodão Formation consists of alternating of quartzose to feldspathic metasandstones, sericitic metasandstones, oligomictic metaconglomerates, metasandstones and quartzites, laminated metapelites, metarhythmites and metasiltites, and quartzites. In turn, the Santo Onofre Group, the Serra da Garapa Formation was subdivided into two lithofacies associations. The first is composed predominantly by quartzites and hematite-rich, graphite-rich and/or manganese-rich metapelites and phyllites. The second lithofacies association comprises staurolite-garnet-quartz-biotite aluminous schist and quartzites. In the Boqueirão Formation predominates metasubarkoses and lithic metasandstones and metasiltites, besides oligomictic metamicroconglomerates. U-Pb geochronological studies (LA-ICPMS) were performed on detrital zircons from these units. Ages ranging were 2870 ± 17–1958 ± 18 Ma and 3177 ± 42–894 ± 38 Ma, respectively. The main primary sources were related to rocks from the basement of the Western Bahia orogeny, of siderian-orosirian age, as well as volcanites and plutonites, both mafic and felsic, with ages between ca. 1.7 and 0.8 Ga, related to the evolution of the precursor basins of the Araçuaí-West Congo Orogen. As secondary sources, results suggest Metavolcanosedimentary sequences and Greenstone Belts of Archean and Paleoproterozoic ages, as well as rocks from the Espinhaço Supergroup and Macaúbas Group. The lithofacies of Serra da Garapa formation, as well as the ages found in detrital zircons, suggest that this formation is chronocorrelate with Rio Peixe Bravo Formation of the Macaúbas Group. Together, these formations, and Matão and Duas Barras Formation represent the pre-glacial unit of the Santo Onofre-Macaúbas basin initiated in Tonian. Some characteristics suggest that the Boqueirão Formation may be correlated to some of the glacial units of this basin. This work suggests that the formations Fazendinha and Serra da Vereda are excluded from the Santo Onofre Group. [ABSTRACT FROM AUTHOR]

The introduction to this special issue on 'Life Writing and Celebrity' outlines the numerous shared concerns of life-writing scholarship and celebrity studies as two of the currently most vibrant fields of cross-disciplinary Humanities research. Providing summaries of the individual contributions and highlighting the connections between them, it points towards the valuable insights to be gained from initiating a more rigorous theoretical and methodological dialogue between the two fields. [ABSTRACT FROM AUTHOR]

Kelantan Dialect is one of Malay dialect that has unique structures. This paper will discuss the uniqueness of kata darjah in Kelantan dialect which is different from other dialects and standard variation. Kata darjah in Kelantan dialect was always misconcept from the aspect of its classification and its position in a sentence. Most researchers tend to classify kata darjah as kata penguat or part of reduplication. The Kelantanese express its language differently compared to standard Malay. Kata darjah in Kelantan dialect has its own structure and function. This paper will discuss every aspect of kata darjah and kata penguat in Kelantan dialect. For this purpose, Kampung Pemanok was chosen as a location of study. Kampung Pemanok is situated in Machang district. An interview was conducted to gather information and the information is based on demography of the place. The data was analysed based on structural framework. The findings of this study show that there are eleven types of kata penguat in Kelantan dialect. Kata darjah in Kelantan dialect was never discussed before. The use and form of kata darjah in standard Malay are different from that of Kelantan dialect. It was hoped that this article will provide some light on the issue of kata darjah and kata penguat in Kelantan dialect. [ABSTRACT FROM AUTHOR]

The Itabira Iron District, located at the northeastern end of the Iron Quadrangle, still presents some uncertainties regarding the tectonic origin of its macrostructure. The Itabira synclinorium is characterized by a large synformal structure in the NESW direction, with anticlines and synclines distributed "en echelon". The analysis of the relationship between the primary structures and the plane-axial schistosity, linear and planar structures, allowed the development of a three-dimensional model for the region. The increase in deformation from E to W, observed from the Cauê mine to the Conceição mine, and the rotation of the axes of the macrostructural folds, characterized by the Cauê, Dois Córregos, and Conceição synclines, are explained in this study by a model with six deformation phases. The increase in shortening from the Cauê mine towards the Conceição mine can be explained based on the flanking fold model. The application of this mechanism to explain kilometric-scale folding has been presented for the eastern flank of the Santa Rita Syncline in the Iron Quadrangle. [ABSTRACT FROM AUTHOR]

The goal of the present paper is presentation of the structural mapping of the karstified limestones, and the relations between the surface and the underground karstification. When mapping on the large scale the frequency of the dip and strike must be increased. Possible intebeds of alien rock must be registered. Measurements of the dip make it possible to ascertain possible plicative deformations. Intercalations of non-carbonate rocks influence the underground water flow and affect the formation, shaping and location of the karst voids as well as the surface karst features. For the understanding of the karstification processes exhaustive collection of structural data, and recognition of broken, crushed and fractured zones within and parallel to fault zones, plus thrust- shear-zones are essential. As spatial organization and dimensions of the underground karst voids, as the surface karst shaping are guided by thrust parallel and fault induced deflection structures. All structural elements, which include tectonic elements as well as bedding planes, lithological changes, lithological partings, less permeable or impermeable interbeds, plus structural elements contribute to the structural framework. It directs both vertical percolation and horizontal streaming within the limestone and influence the frequency, size, spatial distribution, and shape of interconnected karst voids. The later form the speleogenetic network. Due to the permanent denudation the intersection of the Earth surface and the structural framework and speleogenetic network permanently moves downwards. New structural elements emerge while speleological structures change to less recognizable succession objects. The surface of the karst may be characterized as a dynamic, spatial, hydrogeological and speleological succession system permanently affected by the current tectonic activity. [ABSTRACT FROM AUTHOR]

Many participants in and critical observers of the field of in-service training for teachers in Germany are currently reviewing and analysing the situation of the teaching community and schools with regard to the quality of their in-service training, which falls within the responsibility of the individual Federal states (Länder). While several studies have been commissioned recently to analyse the situation empirically, this contribution explores and discusses the current situation from the perspective of the largest association for teacher in-service training, the 'German Association for the Advancement of In-service Training for Teachers' [Deutscher Verein zur Förderung der Lehrkräftefortbildung]. Seen from this perspective, it seems that the qualification and training of the school management staff (headteachers etc.), which usually falls under the responsibility of Federal institutes for teacher training, have recently taken a developmental turn into a positive direction, while there are still many unanswered questions concerning the quality of the training for the significantly larger target group of the teachers in the classrooms, which are also critically perceived by the representatives of educational policy. Among these questions which are concerning crucial issues such as the financial resources of the system and the transferability of new insights gained in inservice training into practice, one of the main the main question remains, whether the different systems of in-service teacher training currently organised by the Länder are able to provide an effective in-service training programme, which will further teacher professionalism and increase the efficiency of the school system. [ABSTRACT FROM AUTHOR]

The Faghur-Siwa Basin is a large sedimentary basin in the westernmost region of the Egyptian Western Desert. The northern portion of this basin has been hydrocarbon productive for the last few decades, making it a subject of frequent geological and geophysical studies. The current study aims to outline the subsurface extent, geometry and structural framework of Southern Faghur-Siwa Basin. The study introduces an approach of using large data set to deduce the structural setting of a sedimentary basin and its applicability to large-scale tectonic features in similar regions worldwide. This study uses satellite-derived potential field data, data of deep wells penetrating the basement, and previous geological studies. The Gaussian filter with a cut-off wave number of 0.0225 (Radian/km) was applied to study deep and shallow anomaly sources in the area while the edge detection methods were used to outline the subsurface boundaries of these sources. The 2.5D forward modeling of magnetic and gravity delineated the basin geometry and basement depth that ranges from 1200 to 5100 m. The basement structure map created by this study showed a complex subsurface structural framework of the Southern Faghur-Siwa Basin that is dominated by N–S, NNW-SSW, NE-SW, and E-W trending faults. • Southern Faghur-Siwa Basin has an N–S axis, 500 km length, and 100–300 km width. • Mafic intrusions underlie the northern, eastern, and western parts of the basin. • Felsic igneous rocks underlie the central and southern parts. • 2.5D gravity and magnetic models reveal basement depths ranging from 1200 to 5100m. • The basin is connected to Kufra Basin from the west and Abu Tarture Basin from east. [ABSTRACT FROM AUTHOR]

The alpha/beta-hydrolases are a family of acid-base-nucleophile catalytic triad enzymes with a common fold, but using a wide variety of substrates, having different pH optima, catalyzing unique catalytic reactions and often showing improved chemical and thermo stability. The ABH enzymes are prime targets for protein engineering. Here, we have classified active sites from 51 representative members of 40 structural ABH fold families into eight distinct conserved geometries. We demonstrate the occurrence of a common structural motif, the catalytic acid zone, at the catalytic triad acid turn. We show that binding of an external ligand does not change the structure of the catalytic acid zone and both the ligand-free and ligand-bound forms of the protein belong to the same catalytic acid zone subgroup. We also show that the catalytic acid zone coordinates the position of the catalytic histidine loop directly above its plane, and consequently, fixes the catalytic histidine in a proper position near the catalytic acid. Finally, we demonstrate that the catalytic acid zone plays a key role in multi-subunit complex formation in ABH enzymes, and is involved in interactions with other proteins. As a result, we speculate that each of the catalytic triad residues has its own supporting structural scaffold, similar to the catalytic acid zone, described above, which together form the extended catalytic triad motif. Each scaffold coordinates the function of its respective catalytic residue, and can even compensate for the loss of protein function, if the catalytic amino acid is mutated. [ABSTRACT FROM AUTHOR]

Stratigraphic and structural interpretative studies have been carried out within the paralic sequence of Agbada Formation in the Niger Delta Basin. The method of study involved integrating sequence stratigraphic techniques with well logs, biostratigraphy, and 3D regional seismic data obtained from several producing fields in the Coastal Swamp depobelt of the onshore Niger Delta Basin. This was targeted at establishing regional sequence stratigraphic and structural framework from well log correlation and seismic mapping so as to better define hydrocarbon leads. Well log correlation using stratigraphic bounding surfaces such as maximum flooding surfaces (MFSs) and sequence boundaries (SBs) indicates that the stratigraphic package was deposited within the Middle to Late Miocene (8.5 to 12.1 Ma) age. Recognized depositional sequences revealed differential thickening and thinning of the associated system tracts (lowstand system tract (LST), transgressive system tract (TST), and highstand system tract) (HST)). This observed stratal behavior has been attributed to the influence of syndepositional tectonic structures that characterize the Coastal Swamp depobelt, which lies within the extensional zone. Flattening of MFSs at various ages indicates observable basinward shift of the depositional center. The genetic units of LST and HST serve as good hydrocarbon reservoir whereas HST and TST constitutes mainly the source and seal packages rocks in the area. Structural interpretation revealed the occurrence of simple/faulted rollover anticline, collapsed crest, regional hanging wall and footwall, horst block, and subdetachment fault structural styles that constitute the key hydrocarbon entrapment mechanisms. Structural top maps show fault-dependent closures which dominate the extensional zone, which could form possible hydrocarbon leads and prospects that should be targeted during exploration studies for development. [ABSTRACT FROM AUTHOR]

The area around the Kabompo and Mwombezhi Domes in the North Western Province of Zambia is characterized by poor outcrop, and as is common with other areas in Zambia, correlation of units between isolated outcrops is complicated by the similarity of lithology in many sections of the stratigraphy. Aeromagnetic data, airborne radiometric and electromagnetic data were used to provide control on correlation between outcrops, and therefore allowed interpretation of a robust structural framework. The two domes are Paleoproterozoic basement-cored anticlines unconformably overlain by Neoproterozoic Roan Group rocks of the lower Katangan Supergroup. The Katangan Supergroup was deposited in an extensional basin formed as part of the breakup of the supercontinent Rodinia. From the geophysical interpretation several normal faults are identified that probably formed during this stage of basin formation, and there is good evidence for at least four regional transfer zones having formed at this time. The fault architecture initiated during the Katangan extensional tectonic event is shown in this interpretation to have strongly influenced the geometry of the Lufilian Fold Belt. Evidence in the domes area suggests that salt tectonics may explain the localization of the regional décollement at the top of the Lower Roan, and provide a structural mechanism for the formation of high-pressure metamorphic rocks in the area. Sinistral reverse faulting and associated folding dominates the Lufilian structural fabric in the east of area, and these faults appear to sole out on the regional décollement. Sigmoidal fold profiles have developed between adjacent fault zones, with east-west oriented fold axes in more distal areas rotating into parallelism adjacent to the faults, suggesting synchronous folding and faulting during north-directed compression. In the north-western part of the study area, fold hinge orientations and basement-cover interactions, indicate north north-westerly directed compression. The study demonstrates that interpretation of combined geological and geophysical mapping at a scale suitable for resolving unit correlations, the deformation sequence and local compression directions, is effective at resolving the extensional and compressional structures that now control the Lufilian Fold Belt structural framework. [ABSTRACT FROM AUTHOR]