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Abstract

This paper studies 38 splits that occurred between 1995 and 2020 in the Czech Republic. Although the initial splits, that took place during the time of democratic transition, were driven by perceived local identity and the historical memory of being a former independent municipality, the splits after 1995 were predominantly driven by economic factors, be it objective underinvestment and a perceived grievance that the mother municipality was not taking care of its fringe parts. In all cases, the mother municipality had failed to communicate with the initiator of a referendum. However, if the central municipality invested in its parts and its political leaders communicated with its citizens, the municipality did not lose its part despites the attempts of secessionist leaders.

Abstract

The paper explores and explains the fragmentation process in Croatian local government during the transition period from 1990 onwards. Special focus is given to the emergence of new municipalities (municipal splits/secessions) that occurred after the new two-tier local government system was established in 1993. Excessive fragmentation of territorial structure at the beginning of the 1990s was a systematic and centrally driven reform that was meant to break with the inherited local government model and break up its territorial structure as radically as possible. While the initial overhaul in 1993 was mostly the result of conscious policy implemented in a top-down manner, subsequent municipal splits were mostly the outcome of local initiatives and lobbying, and were predominantly shaped by local, primarily economic factors, whereas political and cultural factors were of secondary importance. The national institutional context, including criteria and procedural rules for splits, were quite liberal during this whole period, with a moderate tightening-up trajectory. The number of municipalities finally stabilised in 2006, since when there have been no more splits.

Abstract

Walat Formation is equivalent to Bayah Formation. This formation is the beginning of Bogor basin deposition. In this case, age and environment of this formation have been analyzed by previous researchers, but the results of age and environment interpretations have different ranges, especially from its palynological aspect which until now Walat Formation is rarely analyzed using this aspect. This research was conducted to identify the age and depositional environment of Walat Formation in Sukabumi region by using pollen and spores to confirm different interpretations of previous studies. Measure section was carried out in sampling and chemical treatment method was carried out to see palynomorph content in the rock. Furthermore, data analysis was carried out with range of interval zones and pollen grouping based on their environment.

The results show that Walat Formation has Late Eocene age based on the interval zone between first occurrence of Verrucatosporites usmensis and Meyeripollis naharkotensis, and the last occurence of Proxapertites operculatus, Proxapertites cursus, and Cicatricosisporites eocenicus. Walat Formation has fluvial depositional environment characterized by the dominance of Proxapertites operculatus and Proxapertites cursus. The results of this study confirm that the Walat Formation has an Eocene age and a fluvial depositional environment from a palinological aspect.

Abstract

Aeromagnetic data acquired over part of the Anambra Basin is analyzed to determine the structural pattern and sedimentary thickness of the basin. The study area is covered by high resolution aeromagnetic data on sheets 301 (Udi), 302 (Nkalagu), 312 (Okigwe) and 313 (Afikpo), and lies between latitudes 5o30’0’‘-6o30’0’‘ and longitudes 7o0’0”-8o0’0”. The whole area was divided into 25 overlapping blocks of 37.2km2 each and a 2D energy spectral analysis was carried out. Total magnetic intensity data was subjected to filtering and analytical techniques to determine the structural pattern, mineralization potential, depth to the basement, variation in the sedimentary thickness. The structural map generated using the vertical derivatives shows that the major structural orientation of the area is in the ENE-WSW trend and the minor trend is the NW to SE direction widespread all over the area. These structures are as a result of the various near-surface magnetic intrusion within the study area. The spectral analysis result shows two depth layers, the deep and the shallow depth, the depth to magnetic basement for the deep anomalous source ranges from 3.3km to 4.8 4km with an average depth of 3.99km, while the depth to shallow magnetic sources ranges between 0.46km to 0.67km and an average of 0.56km within the area. The mineralization pattern in this area follows the ENE-WSW direction.

Abstract

Studies conducted so far suggest that SEZs are not treated by local authorities as the main mechanism of job creation in a given region. The objective of this paper is to highlight potential mechanisms through which SEZs impact labour markets in poviats (counties) in Poland. To this end we conducted a comparative analysis of changes that had taken place in the labour market over the period 2004–2016 in two groups of poviats with the highest unemployment rate reported in 2004: with and without SEZs. The study does not allow us to unambiguously conclude that SEZs contributed to the improvement of labour market situation in poviats with the highest unemployment rate in Poland. That can be attributed to the fact that SEZs in Poland are highly fragmented as well as to SEZs investors being able to select locations for their investment projects in relatively better developed regions.

Abstract

The Zhob Ophiolite is divided into three detached blocks including the Omzha block. The Omzha block is mapped and divided into lithological units such as ultramafic rock, mafic-felsic rock, and volcanic–volcaniclastic–pelagic rocks. These units are quite deformed and mixed up and are associated with one another by thrust faults. Petrography and geochemistry divide them into gabbro, diorite, plagiogranite, pheno-tephrite and trachy-andesite basalt, trachy basalt, chert, limestone, and mudstone. The ultramafic rocks are dominantly serpentinized harzburgite, dunite, and a minor lherzolite. Petrography of peridotite shows that it may be depleted in nature and may have residual after processes such as partial melting and the melt-rock reaction of a lherzolitic source. The gabbroic rocks are less well-developed and highly deformed. They are cross-cut by diorite, plagiogranite and anorthosite’ intrusions. The gabbro may be the plutonic section of Omzha block’ crust while the intermediate-felsic igneous rocks may have formed by the anataxis of crustal gabbro. The volcanic–volcaniclastic–pelagic rocks unit may be corrected with Bagh complex found underneath the Muslim Bagh Ophiolite. The metamorphic sole rocks of Omzha block are highly deformed and dismembered are comprising of metamorphic facies such as amphibolite, quartz-mica schist, and greenschist.

Abstract

Three dimensional (3D) seismic survey was acquired and processed in Bornu-Chad basin, Nigeria with the aim of detecting and attenuating multiples to aid proper imaging of the subsurface. The 25.5km2 volume was processed using SeisUp processing software on a 32-Node Cluster Infrastructure (CI) hardware. Considering the imaging objectives and depth of interest of 1.2s-4.5s, the minimum, middle and maximum offsets were set at 500-2300m, 2500-4300m and 4500-7300m respectively. Since the study area comprised of dry open land and swampy Lake Chad, vibroseis and dynamite sources were used respectively. Charge depth was 0m (surface) for vibroseis and 25m dynamite. The dataset was first pre-conditioned, normalized, regularized before application of demultiple process. The detection and demultiple processes based on multiple characteristics of periodicity and velocity discrimination were applied as the multiples have comparable velocity with the primaries. The near-surface reverberations and short-period multiples were attenuated using predictive deconvolution and radon transform algorithms. High resolution radon was performed on post-migrated common-mid-point (CMP) gathers and stacked with 1kmx1km target line velocities. Internal multiples were detected and attenuated using data-driven methodology of extended internal multiple prediction (XIMP). Multiples detected were short, long period and interbed multiples on all frequencies ranges of 0 – 90Hz but useful seismic frequency range was between 20Hz and 70Hz. The frequencies and amplitudes of the primaries and multiples were very comparable, therefore great care was taken in the attenuation processes. The results of this work has produced better seismic section for interpretation of subsurface geology in the study area.

Abstract

This paper focuses on the review of electrical geophysical methods such as electrical resistivity and induced polarization as a technique for mineral exploration. It highlights the general fundamental principles of the electrical methods and result from other investigations. Most rock – forming minerals are insulators, and electrical current is carried through rocks mainly by the passage of ions in pore waters. In light of this, most rocks conduct electricity by electrolytic rather than electronic processes. Since metals and most metallic sulphides conduct electricity efficiently by the flow of electrons, electrical method is efficient and important in environmental investigation especially in areas where metallic objects are the targets and also in the search for sulphide ores. The results from various research showed the applicability of these geophysical ground methods, specially the Induce Polarization method, as a support tool in the identification and selection of exploration targets for test drilling.

Abstract

The Oligocene-Early Miocene Nari Formation is widely distributed in the Kirthar thrust-fold belt. The formation in the study area is mainly consist of sandstone and shale. Field observations and detailed petrographic study reveal that these sandstones are mostly fine to medium grained, subangular to subrounded and poorly to moderately sorted. Detrital grains are dominantly quartz ranging in proportion 36-76%, feldspar 7-17% and lithic grains 1-13%, reflecting that these sandstones are compositionally submature. Quartz is mostly monocrystalline with some polycrystalline grains. Feldspar is dominantly plagioclase (albite) with some alkali feldspar (orthoclase and microcline). Lithic fragments are siltstone, mudstone and chert. Biotite and muscovite are present as accessory minerals. Heavy minerals such as apatite, tourmaline, and zircon are present in trace amount. The QFL diagrams show that the sandstones of the Nari formation are subarkose and lithic subarkose. The QtFL, QmFLt ternary diagrams and paleocurrent direction suggest that the sediments were transported from the Indian shield exposed to the northeast of the Nari Basin.