The levels and distribution of 9 trace elements in apples from two orchards in north-east (NE) Romania were measured by means of Atomic Absorption Spectroscopy (AAS) on 42 samples of 9 different apple varieties, with average content ranges of 0.909–4.458 mg·kg−1 Zn, 0.055–0.409 mg·kg−1 Cu, 0.700–2.476 mg·kg−1 Fe, 0.328–0.695 mg·kg−1 Mn, 0.054–0.257 mg·kg−1 Ni, 0.005–0.101 mg·kg−1 Cr, 0.027–0.420 mg·kg−1 Co, 0.413–1.149 mg·kg−1 Pb, and 0.025–0.127 mg·kg−1 Cd. For some apple varieties, Pb contents are 2 times higher than the maximum contents allowed according to national standards, Cd contents are 6 times higher, and in some cases Zn contents also exceed the national threshold, showing preferential accumulation on specific apple varieties. Whilst some research has been carried out on trace element distribution in apples, this study assessed the areal distribution of toxic trace elements in connection to the adjacent roads. The first apple orchard is located near a county road, with reduced car traffic, while the second orchard shares its southern limit with a high-volume traffic road (E583). The results point towards a proportional increase of Pb and, to some extent, of Cd in the samples close to the E583 road in contrast with the other orchard, where no such observation derived. Along the areal distribution of the selected elements, the preferential accumulation of dietary recommended trace elements in different apple varieties was assessed. In matters of daily nutrients content in trace elements, the best sources of Fe, Cu, and Zn in terms of apple varieties are Golden Delicious, Jonathan, and Kaltherer Böhmer.

The precise landing and steering of horizontal wells using conventional mudlogging and Logging While Drilling (LWD) data is a particular challenge for the Lebăda Field, offshore Romania. The use of a new technique of elemental geochemistry analysis (or chemosteering) became an option for the identification of Cenomanian, Turonian–Coniacian–Santonian, Campanian and Eocene strata. This has enabled more accurate placement of the horizontal development wells within the desired reservoir target interval. Geochemical data enabled the identification of chemostratigraphic zones C1, C2, C3 and zone R that correspond to the reservoir section. The application is a result of the geochemical zonation performed using elements and ratios that are sensitive to depositional environment, sea level change, heavy mineral concentrations and siliciclastic input namely: Sr/Ca, Zr/Th, Si/Zr and Si/K. In ascending stratigraphic order, the ratio thresholds of zone C3 are Zr/Th > 11, Sr/Ca > 1.1, Si/Zr < 22 and Si/K < 19, while zone R corresponds to 5.5 < Zr/Th < 11, Sr/Ca < 1.1, Si/Zr > 22 and Si/K > 19. C2 zone is defined by Zr/Th < 5.5, Sr/Ca > 1.1, Si/Zr < 22 and Si/K < 19 and C1 zone is characterized by Si/Zr > 22 and Si/K > 19. The selected geochemical ratios indicate a strong geochemical zonation. In the case of offset wells, 85.9% of the data confirmed the proposed classification and 89.4% for the real-time application case. The zone R shows a strong contrast with the surrounding formations facilitating critical decisions during well placement and geosteering, increasing the reservoir exposure by 28%. The quantitative approach delivered very valuable results, providing a solid foundation to define correlation and well landing intervals. Simultaneously, the cost of the method represents a fraction of the LWD cost and 0.15% of the total project cost, making it very cost effective and a standard approach for future projects.

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This study was conducted on samples taken from the "Fagul Cetății-Iazul nr. 4" tailings pond in the Eastern Carpathians, Romania and is focused on exploring the way in which heavy metals from sulphide rich material are spatially distributed in relation to the geochemical conditions. For comparison, concentrated ore samples from the same area, genetically linked to the Tulgheș lithogroup were also analysed. The mineralogical and chemical composition of the samples was determined along with the main physicochemical parameters such as pH and Eh values. The results show that the mineralogical composition of the tailings is dominated mainly by quartz, chamosite and muscovite-illite, while in case of the processed ore, the main minerals are, as expected, pyrite and quartz. Some traces of jarosite, ankerite, muscovite, gypsum, albite as well as microcline were identified and linked to the geochemical conditions at the surface of the tailings, which revealed an heterogenic environment that can be divided into an acid, oxidizing area in the E and N, characterised by high contents of As, Fe, Pb, Sn and Co and a neutral area in the southwestern slope of the tailings that revealed higher contents of Mn.