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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.

An analysis of the intra-mountain area (Lepsa-Gresu depression), as well as of the Soveja depression at the inner contact point of the Carpathian and sub-Carpathian in Vrancea, focuses on assessing the tourist exploitation of the three communities, as well as on drawing up solutions in compliance with both current tourism trends and the relief predisposition to extend secondary residences and B&Bs. Actually, the 3 settlements, though lying quite close, evince distinctive tourist particulars: Soveja enjoys an older spa resort status and is undergoing revival by introducing new forms of tourism based on current demands; Lepsa is the outcome of land extension of built areas (secondary residences and B&Bs) yet has still to grow into a mature tourist resort in its own right; Gre u (still at a low development pace) can turn into a haven for those who would like to be real estate owners directly involve din the tourist phenomena by opening up B&Bs and motels. Although reality presents us with distinctive space and time solutions for the three locations, we believe that a unitary vision at local level (town halls, local communities), as well as regional/national level could bring about sound local tourism development, with assets such as its natural tourist potential and the regional network capacity revaluation of the national road DN 2D between Moldavia and the Trei Scaune depression and, implicitly, Transylvania. Key words: tourism, modeling, primary residence, secondary residence, agro tourism, ecotourism, tourist landscape., Although the actual realities show distinct time and space evolutions for the three localities, we are of the opinion that a unitary vision at a local level (townhouse, local communities), [...]

The present paper is focused on the mineralogical analysis of soils from two apple orchards (Fălticeni and Sârca) from the North-Eastern region of Romania, geologically located on the Moldavian Platform. 20 samples have been analysed from both areas (11 from Fălticeni and 9 from Sârca), through SEM-EDS and XRD (powder method). The main minerals which were identified are quartz, feldspar, illite and partially calcite. As secondary minerals and trace minerals, chlorite, smectite, glauconite, kaolinite, pyrite, apatite and oligoclase were also identified. Generally, the most abundant mineral is quartz and while for the Sârca area illite is present in notable quantities, in the samples taken from Fălticeni, calcite was identified as a main mineral alongside quartz. The main factor which controls the distribution of minerals within the soils from the two orchards is the geological substratum. The results, correlated with the geochemistry of the soils reveal differences between the soils from the two areas, in matters of their ability to bond certain microelements, especially those with a notable toxic potential, as a function of their mineralogical composition. The principal components' analysis suggests that the distribution of microelements is controlled by the presence of clay minerals, oxides and amorphous material, while Cu points towards an anthropic origin due to agricultural practices. [ABSTRACT FROM AUTHOR]

The Totea-Vladimir structure belongs to the Getic Depression, which was formed at the beginning of the Lower Miocene in the South Carpathians foredeep. In terms of hydrocarbon accumulations, the Sarmatian and Burdigalian formations are of major trade interest. In this context, several technical problems were encountered at the entry of the drilling bits into the Burdigalian formations due to certain abnormal pressures, although their possible occurrence has been monitored in the geologist's cabin. The method used by the geologist was generically named "the Corrected dc-exponent", and it pointed out the entry of the drilling bits into the overpressured Burdigalian formations, but it failed to establish the correct value of the recorded pressures; therefore, the necessary measures to avoid the kicks were not taken in advance. Consequently, in the present paper, to correctly establish both the entry into overpressured areas as well as the value of their pressure, it was used the method proposed by Bourgoyne and Young (1974) which, applied to "H" well, it rightly indicated the magnitude of the pressure at the entry of the drilling bit into the Burdigalian formations. Regarding the causes of the pressure deviations in the Burdigalian formations opened by the "H" well, this paper shows that their presence is closely related to the tectonic events that have controlled the completion of the Totea-Vladimir structure architecture during the Sarmatian period. [ABSTRACT FROM AUTHOR]

The aim of the present study is the subsidence and the evolution analysis of the sedimentary basin related to the Getic Depression over the geological time and within the Totea-Vladimir structure area. In order to achieve the basin subsidence modeling, both information resulting from digging four wells on structure and a series of seismic profiles were used. The results indicate that in the studied area, during the evolution of the sedimentary basin, there were two main periods of increased subsidence, such as Burdigalian and Sarmatian-Meotian. The first period corresponds to an extensional stage while the second one corresponds to a basin developed on strike-slip faults. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to highlight the variations in thermal regime caused by the thrusting of the Tarcău Nappe over the Vrancea Nappe during the New Styrian tectono-genesis. The onedimensional analysis was carried out for the sedimentary column opened by the S300 well within the Șipoteni oil structure (Comănești Basin area). This involved the overlapping of the temperature isolines over the burial curves of the source rock-bearing formations. The computation of temperatures for the time period after the thrust was performed using the equation for heat transfer in an unsteady regime (Angevine and Turcotte, 1983), which requires knowing certain local physical and thermal parameters. Regarding the thermal parameters, given the lack of laboratory or in situ measurements, thermal diffusivity was indirectly estimated, through mathematical simulation, while the thermal gradient of the structure was established using temperature measurements carried out at various depths during the well-digging process. As far as the other parameters (regarding thickness and other aspects of the nappes) are concerned, they were determined based on the back-stripping analysis and the history of sediment burial, being closely related to the local conditions of the nappes. The results obtained have shown that, for the oil structure studied, the influence of the thrust over the thermal regime was not great enough to be considered a major factor in the generation of hydrocarbons from the source rocks. It was most likely the thickness of the thrust nappe which had an essential role. In other areas, where it was considerably larger, the former may have even played a decisive part. [ABSTRACT FROM AUTHOR]

The objective of the present study was the estimation of burial depths for possible hydrocarbon source rocks of Oligocene age from the Vrancea Nappe. The study was carried out on the Șipoteni structure, located within the geographical area of the Comănești Sedimentary Basin, and resulted in a 1D model of the sedimentary column opened by the S300 well. The latter has opened formations belonging to the Sarmatian of the Comănești Basin, as well as to the Lower Miocene, Oligocene and Eocene (the Tarcău and Vrancea nappes). The structure occupies a central position within the Comănești Basin, being the only one within this area with reservoirs in all three structural units. By employing the method proposed by Athy (1930), based on the data from the well files, the laws for porosity variation with depth that apply to the main lithological types within the formations were obtained. The modelling of burial evolution for the formations with source rocks was carried out using the "back-stripping" method, by means of which the initial deposition depths for the possible source rocks were restored. Moreover, the burial curves of these rocks with geologic time were plotted, based on both current and decompacted thicknesses. [ABSTRACT FROM AUTHOR]