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Abstract

Three distinct paragenetic and compositional types of tourmaline were described from the Velence Granite and the surrounding contact slate. Rare, pitch-black, disseminated tourmaline I (intragranitic tourmaline) occurs in granite, pegmatite, and aplite; very rare, black to greenish-gray, euhedral tourmaline II (miarolitic tourmaline) occurs in miarolitic cavities of the pegmatites; abundant, black to gray, brown to yellow or even colorless, acicular tourmaline III (metasomatic tourmaline) occurs in the contact slate and its quartz-tourmaline veins. Tourmaline from a variety of environments exhibits considerable variation in composition, which is controlled by the nature of the host rock and the formation processes. However, in similar geologic situations, the composition of tourmaline can be rather uniform, even between relatively distant localities. Tourmaline I is represented by an Al-deficient, Fe3+-bearing schorl, which crystallized in a closed melt-aqueous fluid system. Tourmaline II is a schorl-elbaite mixed crystal, which precipitated from Li- and F-enriched solutions in the cavities of pegmatites. Tourmaline III shows an oscillatory zoning; its composition corresponds to schorl, dravite, and foitite species. It formed from metasomatizing fluids derived from the granite. This is the most abundant tourmaline type, which can be found in the contact slate around the granite.

Open access

Land use change may modify key soil attributes, influencing the capacity of soil to maintain ecological functions. Understanding the effects of land use types (LUTs) on soil properties is, therefore, crucial for the sustainable utilization of soil resources. This study aims to investigate the impact of LUT on primary soil properties. Composite soil samples from eight sampling points per LUT (forest, grassland, and arable land) were taken from the top 25 cm of the soil in October 2019. The following soil physicochemical parameters were investigated according to standard protocols: soil organic matter (SOM), pH, soil moisture, NH4+–N, NO3–N, AL-K2O, AL-P2O5, CaCO3, E4/E6, cation exchange capacity (CEC), base saturation (BS), and exchangeable bases (Ca2+, Mg2+, K+, and Na+). Furthermore, soil microbial respiration (SMR) was determined based on basal respiration method. The results indicated that most of the investigated soil properties showed significant difference across LUTs, among which NO3–N, total N, and K2O were profoundly affected by LUT (p ≤ 0.001). On the other hand, CEC, soil moisture, and Na+ did not greatly change among the LUTs (p ≥ 0.05). Arable soils showed the lowest SOM content and available nitrogen but the highest content of P2O5 and CaCO3. SMR was considerably higher in grassland compared to arable land and forest, respectively. The study found a positive correlation between soil moisture (r = 0.67; p < 0.01), Mg2+ (r = 0.61; p < 0.01), and K2O (r = 0.58; p < 0.05) with SMR. Overall, the study highlighted that agricultural practices in the study area induced SOM and available nitrogen reduction. Grassland soils were more favorable for microbial activity.

Open access

Abstract

Due to the global oil price crisis in 2014, one of the MOL's preventive/reactive measures was to identify geologically or commercially risky elements within their portfolio. This involved reevaluation of all geologic data from Field A in the Volga-Urals Basin. In re-evaluating Field A, several unexpected challenges, problems and pitfalls were faced by the interdisciplinary team performing the task of building a new database, quality checking, and interpreting data dating back to 1947. To overcome these challenges related to this mature field, new approaches and fit-for-purpose methods were required in order to achieve the overall goal of obtaining a reliable estimation of remaining hydrocarbon potential. In the first phase a first-pass 3D geologic model was constructed, along with wrangling, cleaning and interpreting 70 years of subsurface data. This paper focuses on the main challenges involved in evaluating or reevaluating reservoir aspects of a mature field.

The primary challenges were related to the estimation of remaining in-place hydrocarbon volumes, the optimization of infill well placement, the identification of primary and secondary well targets, the identification of critical data gaps, and the planning of new data acquisitions. The hands-on experience gained during the development of the geologic model provided invaluable information for the next steps needed in the redevelopment of the field.

Open access
Central European Geology
Authors:
Elemér Pál-Molnár
,
Luca Kiri
,
Réka Lukács
,
István Dunkl
,
Anikó Batki
,
Máté Szemerédi
,
Enikő Eszter Almási
,
Edina Sogrik
, and
Szabolcs Harangi

Abstract

The timing of Triassic magmatism of the Ditrău Alkaline Massif (Eastern Carpathians, Romania) is important for constraining the tectonic framework and emplacement context of this igneous suite during the closure of Paleotethys and coeval continental rifting, as well as formation of back-arc basins.

Our latest geochronological data refine the previously reported ages ranging between 237.4 ± 9.1 and 81.3 ± 3.1 Ma. New K/Ar and U–Pb age data combined with all recently (post-1990) published ages indicate a relatively short magmatic span (between 238.6 ± 8.9 Ma and 225.3 ± 2.7 Ma; adding that the most relevant U–Pb ages scatter around ∼230 Ma) of the Ditrău Alkaline Massif. The age data complemented by corresponding palinspastic reconstructions shed light on the paleogeographic environment wherein the investigated igneous suite was formed.

The magmatism of the Ditrău Alkaline Massif could be associated with an intra-plate, rift-related extensional tectonic setting at the southwestern margin of the East European Craton during the Middle–Late Triassic (Ladinian–Norian) period.

Open access
Central European Geology
Authors:
Máté Zsigmond Leskó
,
Richárd Zoltán Papp
,
Ferenc Kristály
,
József Pálfy
, and
Norbert Zajzon

Abstract

Although the Mesozoic rocks of the Transdanubian Range have been the subject of a multitude of different studies, mineralogical research is largely underrepresented. The clay mineralogy of Lower Jurassic (especially the Pliensbachian and Toarcian) strata was broadly investigated earlier; however, systematic high-resolution clay mineralogical studies remain scarce. Here we present a mineralogical study focusing on the Upper Pliensbachian strata of the Lókút-Hosszúárok section, located near the Eplény Manganese Ore Field. We identified dioctahedral smectite, randomly interstratified illite/smectite, illite as 10 Å phyllosilicate, quartz and cristobalite. Based on our new results we propose that the smectite was formed by aging of Mg or Fe hydroxide-silica precipitates. The smectite and cristobalite were presumably formed from the siliceous tests of radiolarians, whose abundance was controlled by a local upwelling system. The occurrence of Pliensbachian smectite in the Lókút outcrop shows similarities with the Úrkút smectites known from both Pliensbachian and Toarcian strata, which implies that similar processes controlled the sedimentation during the Pliensbachian as well as during the black (gray) shale-hosted ore accumulation in the Eplény and Úrkút basins.

Open access

Abstract

In this paper we review five cancellariid assemblages from the Hungarian part of the Pannonian Basin (Börzsöny, Bakony, and Mecsek Mts regions) which yielded 26 species. Ten species are recorded for the first time in Hungary. One species, Scalptia nemethi n. sp. is described as new. A revision of the Hungarian museum collections and historical Hungarian literature is also provided. Sveltia salbriacensis Peyrot 1928 is considered a junior subjective synonym of Petitina inermis (Pusch 1837).

Open access

Cseresznyefák terméshozását és gyümölcsminőségét befolyásoló műtrágya kísérletek eredményei

Results of fertilizer experiments on yield and fruit quality of sweet cherry trees

Agrokémia és Talajtan
Authors:
Ádám Csihon
,
István Gonda
,
Mihály Orosz-Tóth
,
Sándorné Kincses
, and
Imre Holb

Plant nutrition significantly influences yield and fruit quality in fruit orchards. In this three-year study (2016–2018), different fertilizer treatments were compared in an intensive sweet cherry orchard. Trees of cultivar ‘Carmen’ were grafted on Prunus mahaleb ‘Cema’ rootstock, and were trained to free spindle. For NP, NPK and NPKMg treatments, yield ranged between 11.8 and 16.6 kg/tree in the three years, while the yield was 9.1 kg/tree on the control trees. Crop load (fruit amount calculated to the trunk thickness) was 151–166 g cm-2 for fertilized trees, while it was 120 g cm-2 on the untreated trees. Fruit sizes of fertilized trees reached 30 mm in 2018, while the fruit sizes of control trees were smaller with 2.5 mm. Water-soluble dry matter content (%) of the fertilized trees was lower in 2016 and 2017, but higher in 2018 compared to the control plots. In 2017 and 2018, fertilizer treatments resulted in an increase of the content of phosphorus (16–70%), potassium (4–22%) and magnesium (12–43%) in the fruits compared to control plots.

Open access