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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

Numerous ruins around the world lack the radiometric dating due to the scarcity of organic carbon. Here, we present results of radiocarbon dating of mortar samples from an early Medieval church Hohenrätien GR, Switzerland, which was dated to the early 6th century, based on typology. The method of dating mortars, which is currently applied at the ETH laboratory, involves sieving the crushed mortar, selection of grain size 45−63 μm and sequential dissolution resulting in four fractions of CO2 collected in a 3-second interval each. Two mortar samples, which were analyzed using sequential dissolution and one by dating a bulk of lime lump, resulted in a combined radiocarbon age of 1551±21 BP translating to the calendar age of 427−559 AD.

Abstract

The numerical ages available for the sediments on the Danube terraces in the Pest Plain are scarce. In this study, we present quartz OSL and K feldspar post-IR IRSL290 ages for the sandy fluvial, aeolian and slope sediments collected from Danube terraces IIb, III and V.

The feldspar post-IR IRSL290 ages without residual dose subtraction are older than the quartz OSL ages, except for one sample, but the two sets of ages are overlapping within one or two sigma errors.

In the bleaching experiment under natural sunlight during summer, an unbleachable component ranging from 2.5±0.7 Gy to 5.2±0.3 Gy after 30 h exposure to bright sunshine is observed and it corresponds to 3−8% of the measured K feldspar post-IR IRSL290 equivalent doses. These facts indicate that residual dose subtraction would be necessary before age calculation, in most cases.

The saturated fluvial gravelly sand of terrace V of the Danube is older than ~ 296 ka based on feldspar post-IR IRSL290 measurements. This age does not contradict the traditional terrace chronology and the earlier published age data of this terrace. The other studied sediments on the surface of the terraces V, III and IIb deposited much later than the formation of these terraces. They infer aeolian activity and fluvial sedimentation of small streams during the MIS 3 and MIS 2 periods. The age of the dated dune sands with coeval aeolian sediments in Hungary indicate the cold and dry periods with strong wind activity of the Late Weichselian.

Abstract

A geochronological and mineralogical study on the seafloor massive sulfides from the Pobeda hydrothermal cluster at the Mid-Atlantic Ridge was carried out. To improve the reliability of geochronological data, the 230Th/U ages were measured for both the bulk samples and monomineral separates. The oldest age ca. 52 kyr within Pobeda-1 and ca. 107 kyr within Pobeda–2 fields have been obtained. Then, several episodes of hydrothermal activity were identified within both fields up to ca. 0.3 kyr ago and up to ca. 4.3 kyr ago, respectively.

Abstract

The stratigraphy of Late Pleniglacial and Late Glacial fluvio-to-aeolian succession was investigated in two sites located at the Niemodlin Plateau, SW Poland. Lithofacial analysis was used for the reconstruction of sedimentary environments. An absolute chronology for climatic change and the resulting environmental changes were determined based on optically stimulated luminescence (OSL – nine samples) and radiocarbon (three samples) dating methods. Four phases of changes in sedimentary environments were established. The first depositional phase correlates with the Last Permafrost Maximum (24−17 ka) based on the type and size of the periglacial structures, which aggraded under continuous permafrost conditions. During 17.5−15.5 ka (upper Late Pleniglacial), a stratigraphic gap was detected, owing to a break in the deposition on the interfluve area. The second depositional phase took place during 15.5−13.5 ka. During this phase, the first part of the dune formation (Przechód site) and fluvio-aeolian cover (Siedliska site) was deposited. The sedimentary processes continued throughout the entire Bølling interstadial and Older Dryas. In the third phase (Allerød interstadial), soil formation took place. At the Siedliska site, palaeosol represented Usselo soil type, whereas at the Przechód site, there was a colluvial type of soil. The last phase (Younger Dryas) is represented by the main phase of dune formation in both sites. After the Younger Dryas, no aeolian activity was detected. High compliance with both absolute dating methods was noticed.

Abstract

St. George’s Orthodox Church in Drohobych is a wooden monument of sacral architecture, recently registered in the UNESCO World Heritage List. However, clear, unequivocal written sources about the origins of the structure are lacking. Absolute dating was attempted with the dendrochronological method, and it was carried out in a noninvasive way due to the status and value of the object. Construction elements of the church were documented with over 40 macrophotographs. The studies were made for selected elements, displaying distinct perpendicular or tangential cross sections. Most of the elements examined represented fir wood. It turned out that the wood used for the construction of this church was contemporaneous and most likely represented a single construction phase. The 124-year chronology based on correlated curves covers the period 1464–1598 AD. Construction elements with the outermost rings retained indicate that the timber was harvested in the 1590s. In most cases, the outermost rings were lacking, which allowed only for dating terminus post quem. The youngest preserved rings (1598 AD) from the church wood apparently reveal the dates of both the wood harvesting and the structure’s construction. Such a dating may indicate that the church mentioned in the sources as purchased in Nadiyevo in 1657 AD could be the basis for the rebuilding of Drohobych St. George’s Orthodox Church, only adapted to the new conditions. The church later underwent renovation, consisting in reconstruction of the dome in 1821 AD.

Abstract

One of the challenges faced by surveyors in acquisition of accurate spatial data for mining applications is the risk involved in acquiring data in rugged terrains and difficult or inaccessible areas. With the advent of modern technology, accurate geospatial data can now be safely obtained for proper mining documentation periodically. The use of Unmanned Aerial Vehicles (UAVs) for data acquisition in mine surveying has been a viable means of obtaining reliable geospatial data rapidly and efficiently. The main goal of this study is to develop a semi-automatic UAV-based system for the acquisition of spatial data required for the estimation of the volume of earthworks. A DJI Phantom 4 quadcopter was used for the acquisition of image data of the project site, while the images were processed into a Digital Elevation Model (DEM) using Pix4Dmapper v2.0.1, which was then imported into the MATLAB-based system developed for the automatic estimation of the volume of earthworks. The volume obtained from the automated system was thus compared with the volume obtained directly from the Pix4Dmapper software, having specified a contour interval of 1 and an allowable error rate of ±3% as the standard error. While ±1.02% error was observed in the volume estimated using the Pix4Dmapper, the developed automated system yielded an estimated precision of ±0.81% in its volume estimation, which proves to be more robust for automatic volume estimation in terms of accuracy and precision.

Abstract

Establishing a common standardised growth curve (SGC) can substantially reduce the instrumental time for equivalent-dose (De) measurements in optically stimulated luminescence (OSL) dating. Several studies have indicated that different samples have different dose–response curves (DRCs) and therefore that it is difficult to construct a common SGC, although an SGC has been proposed in some cases. In this study, our aims were to construct a regional SGC based on small aliquots of sedimentary quartz from more than 100 samples from different sedimentary environments in the Jilantai Basin in North China and to investigate the applicability of different methods of establishing an SGC for the area. The precision of the De values of aliquots which were obtained using the SGC was compared with those obtained using the single-aliquot regenerative (SAR) protocol. Our results indicate the following: (1) for establishing an SGC using the regenerative normalisation (Re-SGC) method, selecting a suitable re-normalisation dose that is close to double the characteristic saturation dose, 2D0, can reduce the inter-aliquot/inter-sample variation in the form of DRCs within a larger dose range. (2) A common regional SGC can be established for the Jilantai area using the Re-SGC and least-squares normalisation (LS-SGC) methods, which provides reliable dating results within the 200 Gy De range.