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The Sarmatian/Pannonian boundary at the western margin of the Vienna Basin (City of Vienna, Austria)

Abstract

Sarmatian and Pannonian cores, drilled at the western margin of the Vienna Basin in the City of Vienna, reveal a complex succession of marine and lacustrine depositional environments during the middle to late Miocene transition. Two Sarmatian and two Pannonian transgressive-regressive sequences were studied in detail. Identical successions of benthic faunal assemblages and similar patterns in magnetic susceptibility logs characterise these sequences. This allows a correlation of the boreholes over a distance of ~3.5 km across one of the major marginal faults of the Vienna Basin. Biostratigraphic data, combined with rough estimates of sedimentation rates, reveal large gaps between these sequences, suggesting that only major transgressions reached this marginal area. In particular, during the Sarmatian-Pannonian transition, the basin margin completely emerged and turned into a terrestrial setting for at least 600 ka.

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High resolution airborne radiometric and magnetic studies of ilesha and its environs, southwestern Nigeria

wavenumber methods, Society of Exploration Geophysics Annual General Meeting, Calgary, Alberta, Expanded Abstracts. [44] Olowofela, J.A., Badmus, B.S., Ganiyu, S.A., Olurin, O.T., Babatunde, P. (2011): Source location and depth estimation from digitised aeromagnetic data acquired from the basement complex formation. Earth Science India , 4, pp. 136–142. [45] Geosoft INC. (2010). Geosoft INC. 85 Richmond Street, 8 th Floor, Toronto, Ontario, Canada. [46] Frantisek, H., Jiri, P., Jazek, J. Chadina, M. (2009): Out – of-Phase Magnetic Susceptibility of

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The nature of the Pleistocene-Holocene palaeosols in the Gaza Strip, Palestine

during Late Pleistocene in the Negeve. [In:] L. Berkofsky & M. G. Wurtele (Eds): Progress in desert research . Bowman & Littlefield Publishers, Lanham, 302-310. Kukla, G., Heller, F., Liu, X. M., Xu, T. C., Liu, T. S. & An, Z. S., 1988. Pleistocene climate in China dated by magnetic susceptibility. Geology 16, 811-814. Kukla, G. & An, Z., 1989. Loess stratigraphy in central China. Palaeogeography, Palaeoclimatology, Palaeoecology 72, 203-225. Neev, D., Balker, N. & Emery, K. O., 1987

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Evolution of Early Pleistocene fluvial systems in central Poland prior to the first ice sheet advance – a case study from the Bełchatów lignite mine

magnetic susceptibility. Boreas 25, 283-296. Lewin, J. & Gibbard, P.L., 2010. Quaternary river terraces in England: Forms, sediments and processes. Geomorphology 120, 293-311. Lewiński, J., 1928. Utwory preglacjalne i glacjalne Piotrkowa i okolic [Preglacial and glacial deposits of Piotrków and surroundings]. Sprawozdania z posiedzeń Towarzystwa Naukowego Warszawskiego, Wydz. III 21, 49-66. Łanczont, M., Bogucki, A., Mroczek, P., Zieliński, P., Jacyszyn, A., Pidek, A.I., Urban, D., Kulesza, P. & Hołub, B., 2010. Zapis

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Reconstruction and appraisal of Akunu–Akoko area iron ore deposits using geological and magnetic approaches

Abstract

Geological mapping and magnetic methods were applied for the exploration of iron ore deposits in the Akunu–Akoko area of Southwestern Nigeria for the purpose of evaluating their geological characteristics and resource potentials. A proton magnetometer measures the vertical, horizontal and total magnetic intensities in gammas. The subsurface geology was interpreted qualitatively and quantitatively. The downward continuations and second vertical derivatives, the small-sized mineralised bodies and shallow features in the study area were mapped. The faults are trending in the following directions: NE–SW, NW–SE, N–S and E–W groups, while the iron ore mineralisation is structurally controlled by two major groups of fault trends, namely, the NE–SW and NW–SE; the N–S and E–W groups are mere occurrences that do not contribute to the structural control of the iron ore mineralisation in Akunu.

The upward continuation has a linear feature similar to the principal orientation of the regional faults, while Locations 2 and 3 have relatively high magnetic susceptibility zones; suspected to be iron ore deposits. The depths to the magnetic sources ranged from 25 m to about 250 m.

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Geophysical investigation of banded iron ore mineralization at Ero, North – Central Nigeria

Abstract

The banded iron ore mineralization at Ero was investigated using aeromagnetic, resistivity and induced polarization (IP) methods with the aim of characterizing the deposit. Analysis of the aeromagnetic data involved the application of reduced-to-equator transformation, derivative filters, analytic signal and source parameter imaging techniques. Computer modelling of some of the identified anomalies was undertaken. The electrical resistivity and IP methods helped in discriminating between the iron ore and the host rock. The results showed that the banded iron formations (BIFs) were characterized by spherical analytic signal anomalies ranging from 0.035 nT/m to 0.06 nT/m within the granite gneiss and magnetic susceptibility of 0.007-0.014 SI. The iron ore had low chargeability (0.1-5.0 msec) and resistivity (1.5 × 102 to 2.5 × 103 Ωm). Structural features trending in the NE-SW, E-W, and NW-SE were identified, suggesting that the area had undergone many episodes of tectonic events. Depth to the BIF varied from the surface up to about 200 m. The chargeability response of the iron bodies suggested an average grade of 20%-40%, making the prospect for economic exploitation attractive.

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