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The tectonic evolution of SE Anatolia is associated with the collision between the Taurides and the Arabian Platform in the early Cenozoic, after the final closure of the southern branch of the Neotethys ocean during Late Cretaceous to Early Eocene times. The ongoing deformation was characterized by northward movement of Arabia, followed by westward extrusion of Anatolia, having been displaced along the northern and eastern Anatolian transform faults. The neotectonic deformation history between the Anatolian Plate and the Arabian platform since the closure of the southern Neotethyan oceanic basin from Late Cretaceous to present has not been studied in detail paleomagnetically. Therefore we carried out a paleomagnetic study of Mesozoic and Cenozoic rocks at 34 localities along the Bitlis-Zagros suture zone in SE Anatolia located in the boundary region between the Taurides and the Arabian platform and delimited by the Dead Sea Fault. Paleomagnetic results from the area show clockwise rotations of 35.6° ± 14.1° and 26.7° ± 8.0° with respect to the African plate from Upper Jurassic - Lower Cretaceous and Upper Cretaceous limestones, respectively. The paleomagnetic results indicate also an earlier deformation/opening due to the Dead Sea Fault Zone (DSFZ). Farther north on the Tauride Block, counterclockwise rotation of −34.5° ± 12.5° is recorded by Upper Cretaceous limestones. In the SE of the study area on the northern margin of Arabia, however, smaller counterclockwise rotations of -12.3° ± 8.3° and −2.5° ± 10.0° in Late Cretaceous and −12.7° ± 13.6° in middle Eocene rocks show relative tectonic stability. Middle Miocene rocks close to the suture zone show counterclockwise rotation by about −39.4° ± 10.9°, while farther away from the suture zone counterclockwise rotations of −21.9° ± 9.9° and −7.5° ± 5.8° are observed. Paleolatitudinal motion from south to north from the Late Jurassic to the Present is in concordance with the apparent polar wander path of Eurasia and Africa.

The Galería Complex is a cave sediment succession at the Atapuerca paleoanthropological site (Burgos, Spain) that offers detailed environmental information about the late Middle Pleistocene, especially the period between marine oxygen isotope stages MIS10 and MIS7. Previous studies have reconstructed the chronology and detailed the environmental development of this key succession. We introduce rock magnetic climate proxies from the sedimentary units of the Galería succession that we correlate with the global climate record as represented by the marine oxygen isotope record. The cave sediment sequence consists of five infilling phases, four of which were sampled at high resolution across a 5 m thick composite profile. We propose a novel goethite climate proxy along with a frequently used ultrafine ferrimagnetic mineral proxy for paleoclimate reconstruction and detailed chronostratigraphic correlation with isotope stages and substages MIS10/MIS10-9, MIS9e-a and MIS8. The proxies reveal new paleoenvironmental information about paleoprecipitation and indicate that MIS9e was a humid (∼650 mm/year maximum annual precipitation) and intense interglacial in northern Spain that declined in steps into the globally weak glacial stage MIS8. MIS8 consisted of drier periods with 430–510 mm/year annual precipitation and at least one humid substage (600 mm/year)., Junta de Castilla y León (Spain) and the European Regional Development Fund (ERDF) (BU235P18) and the research projects CGL2016-77560-C2, CGL2018-093925-B-C31, and CGL2017-89603-R of the Spanish Ministry of Science and Innovation and PID2019-108753 GB-C21 and PID2019-105796 GB-I00 of the Spanish State Research Agency (AEI/10.13039/501100011033) and ERDF funding (European Union). B. Bradák acknowledges financial support from project BU235P18 (Junta de Castilla y León, Spain) and the European Regional Development Fund (ERDF). M. Calvo-Rathert acknowledges funding from the Fulbright Commission and the Spanish Ministry of Science Innovation and Universities (PRX19/00148) for a research stay at University of Hawaii at Manoa.

The eastern Aegean region has undergone north dipping subduction in the Oligocene, continental collision and then Miocene-Pliocene extension, which is associated with widespread Miocene volcanism. The aim of this study is to assess the possibility of block rotations due to stress variations in the Dikili (İzmir) province, Western Anatolia, based on paleomagnetic data obtained from 35 independent sites in addition to results from 19 sites in earlier studies. The lower Miocene Yuntdağ volcanic rocks were emplaced in three different structural blocks, the Dikili, Zeytindağ and Bergama blocks. Clockwise rotation is found in the Dikili and Zeytindağ blocks that varies from R (± DR) = 12.5° (± 7.4°) in the west to R (± DR) = 35.6°± (13.2°) in the east, respectively. In contrast, a counterclockwise rotation of R (± DR) =-38.1° (± 6.4°) resulted in the Bergama block, in the north of the Dikili and Zeytindağ blocks. A scissor-like basin evolution is suggested during the opening of the Bakırçay graben which led to counterclockwise rotation of the Bergama block and clockwise rotation of the Dikili and Zeytindağ blocks after lower Miocene to present. The rotation pattern derived from results of this study demonstrates that localized small scale deformation due to basin evolution besides regional affects must be considered as part of the deformation matrix in this area., Annals of Geophysics, 64 (6), ISSN:1593-5213

A paleomagnetic study of Cretaceous arc type rocks in the Central-Eastern Pontides and in the Southeastern Taurides investigates the tectonic and paleolatitudinal evolution of three volcanic belts in Anatolia, namely the Northern and Southern Volcanic Belts in the Pontides and the SE Taurides volcanic belt. The paleomagnetic data indicate that magnetizations were acquired prior to folding at most sampling localities/sites, except for those in the Erzincan area in the Eastern Pontides. The Southern Volcanic Belt was magnetized at a paleolatitude between $$23.8_{-3.8}^{+4.2}$$ °N and $$20.2_{-1.2}^{+1.3}$$ °N. Hisarli (J Geodyn 52:114–128, 2011) reported a more northerly paleolatitude ( $$26.6_{-4.6}^{+5.1}$$ °N) for the Northern Volcanic Belt. The comparison of the new paleomagnetic results with previous ones in Anatolia allows to conclude that the Southern Volcanic Belt in the Central-Eastern Pontides was emplaced after the Northern Volcanic Belt as a result of slab-roll back of the Northern Neotethys ocean in the Late Cretaceous. In the Southeast Taurides, Upper Cretaceous arc-related sandstones were at a paleolatitude of $$16.8_{-3.8}^{+4.2}~$$ . The Late Cretaceous paleomagnetic rotations in the Central Pontides exhibit a counterclockwise rotation of $$R\pm \Delta R=-37.1{}^\circ \pm 5.8{}^\circ$$ (Group 1; Cankiri, Yaylacayi Formation) while Maastrichtian arc type rocks in the Yozgat area (Group 2) show clockwise rotations R + ΔR = 33.7° ± 8.4° and R + ΔR = 29.3° ± 6.0°. In the SE Taurides counterclockwise and clockwise rotations of $$R\pm \Delta R=-48.6\text{ }\!\!{}^\circ\!\!\text{ }\pm 5.2\text{ }\!\!{}^\circ\!\!\text{ }$$ and $$R\pm \Delta R=+34.1\text{ }\!\!{}^\circ\!\!\text{ }\pm 15.1\text{ }\!\!{}^\circ\!\!\text{ }$$ are obtained (Group 4; Elazig Magmatic Complex). The Late Cretaceous paleomagnetic rotations in the Pontides follow a general trend in concordance with the shape of the suture zone after the collision between the Pontides and the Kirsehir block. The affect of the westwards excursion of the Anatolian plate and the associated fault bounded block rotations in Miocene are observed in the east of the study area and the SE Taurides.

Geophysical Journal International, 155 (2), ISSN:0956-540X, ISSN:1365-246X

The magnetic susceptibility of loess from the Ily Basin, northwestern China shows maximum values in S0 paleosols but minimum values in other paleosols, the mechanism of which has been well debated. In this work, systematic magnetic measurements were made on a representative section from Neleke county. The results show that the loess horizons (L1, L2 and L3) have multi-domain magnetite grains of aeolian origin, S0 is characterized by production of pedogenetic ultrafine-grained ferrimagnetic minerals, and the other paleosols (S1, S2, and S3) are characterized by the formation of nonferrimagnetic minerals associated with waterlogging. The correlation between the low concentration of ferrimagnets, high paramagnetic content, high magnetic coercivity remanence, fine ferrimagnetic grain size and intensified pedogenesis suggest two competing processes of pedogenetic enhancement and pedogenetic depletion in the lower paleosols. Pedogenetic depletion dominates and is responsible for the low susceptibility. Changes in magnetic grain size distribution occur during pedogenetic depletion. The susceptibility variations are of multiple origins in the loess of the Ily Basin. Pedogenetic enhancement, pedogenetic depletion, and allochthonous input of magnetic minerals should all be taken into account to explain the variations of magnetic parameters.

The Stari Slankamen loess-palaeosol section is located on the northeastern part of the Srem Loess Plateau (Vojvodina region, North Serbia). The c. 40-m thick cliff comprises loess intercalated with 9 major palaeo pedocomplexes and can be considered to be one of the most important Quaternary sections in the Carpathian (Panonnian) basin. Here we present new magnetostratigraphic and aminostratigraphic evidence that demonstrates the importance of the site in terms of its age and the long-term palaeoclimatic record it preserves. Directional palaeomagnetic data, obtained through alternating field demagnetization demonstrates the presence of reversed polarity below a profile depth of 36 m indicating a Matuyama chron age of this interval. This interpretation is confirmed by new high resolution palaeomagnetic investigations (434 oriented samples) from the lower part of the profile. The new magnetic susceptibility record and aminostratigraphy indicate a missing pedocomplex (V-S2), with an erosional unconformity represented by a distinct gravel layer. The combined new magnetostratigraphic and aminostratigraphic based age model requires a significant revision of hitherto published chronostratigraphic subdivisions at the site. The relative completeness and long time frame covered by the section is unusual in European loess sequences. Hence, the sequence could form the basis of a continental scale stratigraphic scheme that would alleviate much current chronostratigraphic uncertainty and enable more broad-scale climatic reconstructions. The section also provides a rare opportunity to investigate detailed and long-term climatic change over the Middle Pleistocene in a region influenced by air masses originating from high and middle latitudes, as well as the North Atlantic and Mediterranean. The changing relative importance of these air masses through time provides insight into local and regional atmospheric systems and their evolution through the last c.1 Ma. The section can thus be considered as one of the key climatic archives in the Europe.

A revision of Jurassic palaeomagnetic data from Iberia has been carried out in order to investigate the consistency between the palaeomagnetic information and the tectonic models proposed for the western Mediterranean. Due to the presence of a widespread (but partial) remagnetization which affected most Jurassic sediments in Iberia, selection criteria have been designed to avoid completely remagnetized sites. A total of 72 sites have been considered for the palaeomagnetic discussion (35 sites from the Messejana–Plasencia dolerite dyke, 14 sedimentary sites from the Iberian Range and 23 sites from the Betic Cordillera). Three palaeopoles for Iberia have been selected (from the Iberian Massif and from the Iberian Range) for the period around 200 Ma, the Toarcian–Aalenian and the Oxfordian. Data from the Subbetic Zone (Betic Cordillera) are used to constrain the palaeolatitude of the Iberian microplate. Iberian data are in general agreement with the BC02 master curve and the reconstruction parameters used to transfer the Iberian data to Europe, but lower palaeolatitudes than predicted by BC02 master curve are observed in Iberia for the Late Jurassic. Iberia reached a maximum in palaeolatitude during the Toarcian–Aalenian (the reference point of Madrid was at about 37°), and since then, the palaeolatitude decreased (Madrid was at 22° by the Kimmeridgian). Tectonic reference models for the Western Mediterranean (Stampfli and Borel, 2002, 2004) do not fit the Iberian declinations and palaeolatitudes. New palaeogeographic reconstructions are proposed for the Hettangian–Sinemurian, the Toarcian–Aalenian and the Oxfordian.

A new paleomagnetic study was carried out on the Findikli formation in the Amasya region, which is to the north of the Ankara-Erzincan Neotethyan suture zone, in order to better understand the paleogeographic evolution of the Pontides tectonic belt during the Maastrichtian. Samples were collected from volcanoclastic sandstones and lavas at 51 sites. Rock magnetic experiments identified pseudo-single domain (PSD) titanomagnetite as the main magnetic carriers at the majority of sites. Progressive thermal and alternating demagnetization revealed that the characteristic remanent component is removed between 400 and 580 °C or 20–100 mT, respectively. A high temperature component, which indicates the presence of titano-hematite, is found only in some lavas. Declinations show a systematic dispersion across the study area related to tectonic rotations about vertical axes. Inclinations are consistent, however, and yield a mean paleolatitude of 20.0°N ± 2.5° for the Maastrichtian. Comparison of the results from this study with the reference direction of the East Pontides from the Turonian–Campanian is best explained with a model involving slab roll-back and marginal basin formation between 90 and 65 Ma period.

Inactive stalagmites from the Silberen cave system and its surroundings (Muota Valley, Central Switzerland) have been dated by the 230Th/U method (alpha spectrometry and TIMS). Several samples yielded ages of approximately 200 ka (MIS 7) and 320 ka (MIS 9), others were beyond the upper limit of the method (about >350 ka) or might have behaved as open systems with respect to uranium. The following complementary dating methods were applied: 234U/238U, paleomagnetism, palynology and electron spin resonance. Paleomagnetism yielded positive inclination of the natural remanent magnetization of two stalagmite samples, corresponding to the Brunhes-epoch ( The uplift rate of the mountains, the corrosion rate of the karstified surface and the incision of the valley bottom, suggest that karstification started 4 to 3 Ma (Middle to Upper Pliocene). The dated speleothems are therefore substantially younger than the beginning of speleogenesis. Inaktive Stalagmiten aus dem Silberen-Hohlensystem und dessen Umgebung (Zentralschweiz) sind mittels der 230Th/U-Methode (Alpha-Spektrometrie bzw. TIMS) datiert worden. Einige Proben ergaben 230Th/U-Alter zwischen von 320 ka (MIS 9) und 200 ka (MIS 7), andere lagen ausserhalb des Zeitfensters der 230Th/U-Methode (>350 ka), wieder andere konnten offene Uran-Systeme gebildet haben. Erganzend zu den numerischen Datierungen wurden versuchsweise weitere Datierungsmethoden eingesetzt: 234U/238U, Palaomagnetik, Palynologie und Elektronen-Spin-Resonanz. Die Palaomagnetik zeigte bei den zwei untersuchten Tropfsteinen eine positive Inklination der naturlichen remanenten Magnetisierung, was der Brunhes-Epoche ( Aus der bekannten Hebungsrate des Gebirges, dem korrosiven Abtrag der Karstoberflache sowie der Eintiefung des Muotatals wurde abgeleitet, dass die Verkarstung im Untersuchungsgebiet vor 4 bis 3 Ma (Mittleres bis Oberes Pliozan) begonnen hat. Die bislang datierten Karsthohlensedimente sind nach diesem Modell also wesentlich junger als der Anfang der Speleogenese.

High-resolution paleosecular variation (PSV) can play an important role in sediment dating and for understanding the temporal characteristics of the geodynamo of the Earth's magnetic field. In this article, based on magnetic susceptibility correlation, a composite sediment profile has been compiled from a ~ 16 m long core (HN-2) and a ~ 8 m deep well (HN-3) in Shuangchiling maar lake, a crater basin located on Hainan Island, Southern China. Fine and homogeneous silty clay corroborates with a stable, continuous and undisturbed deposition. A U-channel-based paleomagnetic study, constrained by AMS14C chronology derived from leaves, plant debris and woods, and supported by rock magnetic data, indicates that the lake sediments document a reliable paleosecular variation (PSV) record since ~ 9000 cal. year BP. Comparison of our PSV features with other records from lakes Biwa (Japan), Erhai (China), Baikal (Russia) as well as archaeomagnetic records demonstrate that the inclination pattern is generally synchronous within chronological uncertainties, suggesting further PSV dating may be valuable for stratigraphic correlation on a regional scale.

Relative paleointensity records from the northern South China Sea, northwest Pacific Ocean were studied in two gravity piston cores. Continuous mineral magnetic and paleomagnetic measurements were made using discrete sediment samples. Detailed rock magnetic parameters, such as thermomagnetic and high-field hysteresis data, indicate that pseudo-single domain magnetite in a narrow range of grain-size and concentration is the main contributor to the remanent magnetization. The uniform magnetic mineralogy meets the commonly accepted criteria for establishing relative paleointensity records. The relative paleointensity (RPI) curves were constructed by normalizing the natural remanent magnetization (NRM) with isothermal remanent magnetization (IRM), both in the 20-60 mT demagnetization state. Dating constraints have been provided by radiocarbon ages in the upper 400 cm of both cores. Furthermore, we have correlated our paleointensity records with NAPIS-75, S.Atlantic-1089, Sint-200 and NOPAPIS-250 to determine the chronological RPI framework for the South China Sea (SCS-PIS). Although some temporal offsets of paleointensity features between the different records have been recognized, their similar shape suggests that relative paleointensity on the 10(3)-10(4) year scale is globally coherent and can provide an age framework for sediments independent of delta(18)O ages. (C) 2009 Elsevier B.V. All rights reserved.

The paper addresses the controversial question of the role of clay-sized dust in the formation of paleosols in coastal eolianites, Israel. At the Habonim type section, the pedocomplex dated by archaeology and luminescence to 45-135 ka ago shows at least three paleosols, not separated by non-soil sediments. The oldest reddish paleosol (apparently related to MIS 5) is magnetically enhanced, leached from carbonates, with signs of bioturbation and strongly aged clay coatings. The reddening is due to very fine, similar to 20 nm, poorly crystallized, super-paramagnetic (SP) hematite, as determined by Mossbauer studies. In subsoil, lithorelics of eolianite are found. Over time, the soil surface aggraded due to accelerated fine dust accumulation alongside local slope wash. On younger materials formed magnetically depleted vertisols, dominated by smectite-type expandable paramagnetic clays. In thin sections, vertisols exhibit strong stipple-speckled and striated b-fabric due to shrink-swell processes, impregnative calcite nodules and Fe-Mn redistribution. The uppermost hydric vertisol shows the strongest expression of juxtaposed features of recurrent calcite and Fe precipitation. This paleosol developed on colluvial soil materials, as evidenced by mixing of clay coated and uncoated grains of quartz and calcite allochems. Mossbauer spectra show high amounts of Fe(III) incorporated in the clay structure, low amounts of SP goethite and absence of SP hematite. Whilst magnetic susceptibility drops in vertisols to minimal values, ferrimagnetic grain sizes increase. The latter along with differences in the hierarchy of microfabric features is taken as indication for lithologic discontinuities which may have resulted from continuous, albeit variable and low-intensity, input of eolian clay from both remote Saharan and local sources, roughly dated to the earlier to middle part of the Last Glacial.

The Matuyama/Brunhes boundary (MBB) in loess sections of the East European Plain, one of the greatest areas of global loess distribution, is a highly debatable issue. The ambiguity of the MBB position here results from the complexity of loess/soil magnetization processes and an apparent delay in loess remanence acquisition, and from the uncertainties of pedostratigraphic interpretations. In the Don Glaciation area, the MBB is unanimously placed below the Don moraine, although the exact position is still controversial. In the sites of the Northern Azov Sea, the MBB is, however, placed in the loess horizon considered to be the equivalent of the Don moraine in the north. The inconsistency of this interpretation is demonstrated by detailed magnetostratigraphic and pedostratigraphic studies in the western sites of Zaporozh'e (Dnieper basin), Novaya Etuliya (Lower Danube basin) and Roxolany (Lower Dniester basin). In all these sites, albeit with certain minor discrepancies, the MBB is found two or three interglacial palaeosols below the Don loess, which is overlain by the good stratigraphic marker of the Vorona pedocomplex, a thick polygenetic red-brown palaeosol formed supposedly in a Mediterranean climate. Here the MBB is placed in a ‘quadruple soil’ unit, termed “Roxolany loess/soil suite”, which consists of four closely spaced, strongly calcareous soils occupying an interval between the Don loess on top and the earlier well-developed Bobrov (?) loess with reversed Matuyama magnetization. The Roxolany suite can possibly be correlated with the three palaeosols of the pre-Don Ilyinka unit of the Russian Unified Stratigraphic Scheme and thus confirms the interpretation of the MBB in the central areas of the East European Plain as to the interval between the Ternovka (second-pre-Don) palaeosol and the Troitsk (third pre-Don) palaeosol.

Catenary changes, archeology, micromorphology, and magnetic mineralogy of paleosols in coastal sands, Israel, were investigated under chronostratigraphic control by available luminescence datings from adjacent sites. At the outlet of Hadera stream, eolianites (Hebrew: "kurkar") underlie paleosols with Epipaleolithic (approx. 17-20 ky) artifacts at the top and occasional Mousterian (>40 ky) artifacts in the subsoil. The optically stimulated-luminescence/infrared stimulated-luminescence (OSL/IRSL) dates (>50-12 ky) from adjacent sites roughly agree with the archeological findings. The paleosols show a magnetically depleted Vertisol superimposed on a magnetically enhanced cumulative Chromic Luvisol (WRB) (USDA: Rhodoxeralf, Israeli class.: Hamra). The latter contain approx. 0.25 mm thick, isotropic clay infillings distinctly separated from the soil matrix. These infillings are tentatively interpreted as the result of strong environmental disturbances, such as surface desiccation, subsequent waterlogging, and enhanced dust deposition, presumably at the time of the Last Glacial Maximum. In addition to the massive accumulation of eolian dust, diverse pedogeomorphic changes lagging in time from the onset of climatic deterioration may have taken place in coastal settings. Recurrent desiccation cracks may have exposed subsurface materials repeatedly to sunlight, consequently resetting the luminescence signal. The eolianite sequences are thus distinct from loess/paleosol sequences from temperate climates and have to be treated more rigorously at a site-specific level.

Three lacustrine sections in the Nihewan Basin, Xiaodukou, Donggutuo and Xiaochangliang (40.1–40.4°N; 114.6–114.7°E), were closely sampled for magnetostratigraphic and deposition cycle analysis. Rock magnetic investigations show that the characteristic remanent magnetization of the sediments is mainly carried by magnetite and hematite. The Xiaodukou sequence is one of the most complete sections in the basin and has recorded substantial parts of the Brunhes and Matuyama chrons back to the termination of the Olduvai subchron. Several subchrons within the Matuyama period have been documented such as the Jaramillo, the Cobb Mt. and others. The Matuyama/Brunhes boundary, the Jaramillo, as well as the Cobb Mountain events were observed also at Donggutuo. On the basis of grain size and susceptibility data and of field investigations, the sections are divided into two longer lasting lacustrine episodes with a fluvio-lacustrine deposit in between. They are structured by 15 high-frequency deposition sub-cycles. In each cycle, the grain size fines upwards, while magnetic susceptibility decreases. This behavior is due to cyclic water level change of the ancient lake Nihewan. At Xiaodukou, the variations of the 0.2 to 7.5 μm grain size fraction can be correlated with the marine oxygen isotope stages OIS 64–OIS 11. The grey-green clayey to silty Paleolithic stone artifact layers at Xiaochangliang and Donggutuo are located at depths of 55.4 m and 43–38.7 m, respectively. They were buried when the lake-level was rising. The artifact layers have been deposited around the Cobb Mountain event during the sedimentary sub-cycle 6 of the older lacustrine phase corresponding to OIS 35, 36. Thus in contrast to the results of other studies, the estimated age of the Xiaochangliang stone artifact layer does not exceed 1.26 Ma, while the Donggutuo stone artifact layers date back to 1.21–1.15 Ma. This age determination brings the Nihewan hominids in close relation to the findings of Homo Erectus at Lantian on the Chinese Loess Plateau.

The paper presents results demonstrating the possibility of using data on paleosecular magnetic variations for correlation of young deposits. Using Holocene deposits of the Aral Sea as an example, it is shown that the combination of paleo-and petromagnetic data can be used to reliably correlate sections in presently isolated parts of a basin, as well as to correlate paleohydrologic events and estimate their age with regard for absolute radiocarbon datings. It is established that the most significant drop in the Aral Sea level occurred more than 2000-2500 yr ago and less significant drops that occurred later are dated at about 1500, 750-1050, and 270-500 yr ago. © Pleiades Publishing, Ltd. 2007.

The magnetostratigraphy of the Lower–Middle Toarcian has been established in two well-dated stratigraphically expanded sections: the Sierra Palomera and the Arino sections, located in the Iberian Range, in central-eastern Spain. Two magnetisation components could be isolated by thermal cleaning: a secondary syntectonic component of always normal polarity unblocking at intermediate temperatures up to 450 °C/475 °C (A component) and a high temperature unblocking component up to 575 °C (B component). The B component passes fold and reversal tests and is considered the characteristic remanent magnetisation of primary origin. The first Toarcian palaeomagnetic pole for Iberia has been obtained: Plat = 77.4°, Plon = 241.3°E (dm = 5.4° dp = 6.0°). Five pairs of normal and reversed polarity zones were calibrated to regional ammonite subzones. The pattern can be calibrated to other Toarcian magnetostratigraphic studies, but provides a more detailed biostratigraphic framework. A refined magnetic polarity time scale is proposed for the Lower–Middle Toarcian.

Loess/paleosol sequences in the western Black sea area at Roxolany (48 m thick) and Novaya Etuliya (30 m thick) were studied using paleo- and rock-magnetic methods in conjunction with micromorphology and Mossbauer investigations. Although seemingly complete, the sites show variability in the type and number of loess/paleosol cycles, and inconsistency of the Matuyama/Brunhes boundary (MBB) stratigraphic position. At Roxolany, nine pedocomplexes (PK) and several incipient paleosols, alternating with thick loesses, were observed with the MBB being located between PK 6 and PK 7 . At Novaya Etuliya, 13 PKs occur upon terrace XII with Khapry fauna and with the MBB in the upper part of PK 7 and the Jaramillo subchron within the lower part of PK 8 . The depth functions of rock magnetic properties, organic carbon content C org , both for bulk samples and for clay extracts, along with micromorphology and Mossbauer spectra, allowed objective identification of individual soils within PKs, and maximizing the resolution of paleopedological reconstructions of global climatic stages. The Mossbauer studies demonstrate that paleosols are basically enriched in ferric montmorillonite. Oxidized magnetite, ultrafine iron hydroxides and hematite are intimately associated with clay minerals. In contrast, Fe-compounds in loess consist mainly of ferrous silicates. These data indicate that the paleosol magnetism is basically of bio-chemogenic origin and is related to pedogenic transformation of Fe-compounds in a changing environment, while loess magnetism is primarily detrital. Pedogenic magnetically “soft” and partly oxidized magnetite may also originate during or even after burial. This ensuing transformation of Fe minerals in paleosols seems to be crucial for the understanding of the timing of natural remanent magnetization (NRM) in subaerial sediments. Given that paleosols formed on the similar parent material (loess), their typological variability seems to depend on climate and/or chronology. Hence, the different paleosol types from Roxolany and Novaya Etuliya provide key information for intra- and inter-regional correlation of loess/soil sequences, and represent valid paleoclimatic proxies.

The Andes of northern Chile currently experience a phase of relief rejuvenation as indicated by valleys that are >1000 m dissected into pediplains. However, it has been unclear when this phase of relief enhancement started. This paper discusses the use of palaeomagnetic chronologies from four sections in the Taracapá-Region (northern Chile) to assess this age. The sections are located in distal and proximal positions. Sediment accumulation occurred between c. 22.5 and 8/ 7.5 Ma with a hiatus that possibly spans a time interval between c. 19.5 and 11 Ma. The magnetic polarity chronologies suggest a preferred age between 8.0 and 7.5 Ma for the time when relief growth started. In proximal positions, however, alternative correlations suggest an age of 8.5 Ma. In addition, the palaeomagnetic data reveal no rotation of the analysed strata, suggesting a minimum age of c. 22.5 Ma for the tectonic block rotation south of the Arica deflection. © 2005 Blackwell Publishing Ltd.

To elucidate the way in which past climatic changes are encoded magnetically by wind-blown silt, we have investigated two stratigraphic sections in the Chinese Loess Plateau (Xiagaoyuan, in the cool, dry western plateau and Houzhuang, in the warmer, wetter central plateau). In view of the anticipated importance of magnetic particle size, we have determined grain-size distributions from > 50 μm down to ∼10 nm by sequential sieving, sedimentation and centrifugation of typical loess and palaeosol material from the two sites. For the essentially unaltered loess, the main susceptibility contribution lies in the 20–50 μm fraction, with only ∼20% of the signal residing in the 1 (corresponding to oxygen isotope stage 5) at Houzhuang, and a peak value of 4.8 × 10 8 atoms/g was observed, almost identical to that found by other workers for the same horizon at Luochuan. A similar profile at Xiagaoyuan reveals three peaks corresponding to palaeosols S 1 S 1 (2.6 × 10 8 atoms/g), S 1 S 2 (3.3 × 10 8 atoms/g) and S 1 S 3 (3.3 × 10 8 atoms/g). Conversion of these concentrations into 10 Be fluxes indicates low dust accumulation during warmer climate episodes. At these times pedogenic susceptibility enhancement is favoured, the amounts of which imply palaeoprecipitation slightly higher than today for S 1 S 3 at Xiagaoyuan, but somewhat lower than today for S 1 at Houzhuang.

This paper presents the results of the paleomagnetic studies of the Naroch and Svir lake bottom deposits in Belorussia. The objects of study were nine columns of lake-floor sediments, totaling 6.50 m in thickness, collected using a special-type core sampler which did not disturb the structure of the sample material. The absolute dating of the sediments was performed by a radiocarbon method using the macroremains of the organic matter (grass). The columns of the sediments were correlated using their absolute ages, lithologies, and magnetic susceptibility values. All sedimentary rock columns showed a good agreement of the inclination and declination components of the natural remanent magnetization (ChRM) distinguished in all sedimentary rock columns using alternative magnetic field cleaning. The data obtained for all rock columns were summed up to produce the composite curves of ChRM declination and inclination variation for the sediments of these lakes. These data were compared with the archeomagnetic and limnomagnetic data available for Central and East Europe. All records of the paleosecular geomagnetic variations (PSV) showed a good agreement in terms of the morphology of the ChRM declination and inclination. At the same time the sediments of the Belorussian lakes showed a systematically older age and the lower magnitudes of the ChRM declination and inclination variations compared to the other PSV records available. These eects can be explained by the presence of some postdeposition remanent magnetization (PDRM) in the sediments of the Belorussian lakes and by the addition of some "aged" carbon (without 14 C) to the lake from the surrounding carbonate rocks. The basic features of the geomagnetic field variations in Europe are discussed for the last 10-12 thousand years.

A detailed rock magnetic investigation of loess/palaeosol samples from the section at Lingtai on the central Chinese Loess Plateau (CLP) is presented. Thermal demagnetisation of isothermal remanent magnetisation (IRM) and Curie temperature measurements suggest the presence of magnetite, maghemite and hematite as remanence carrying components. Bulk and grain size fractionated samples have been analysed using coercivity spectra of remanence acquisition/demagnetisation curves, which identify four main remanence carriers in different grain size fractions of loesses and palaeosols. A linear source mixing model quantifies the contribution of the four components which have been experimentally derived as dominating endmembers in specific grain size fractions. Up to two thirds of the total IRM of the palaeosols are due to slightly oxidised pedogenic magnetite. Two detrital components dominate up to 90% of the IRM of the loess samples and are ascribed to maghemite of different oxidation degree. Detrital hematite is present in all samples and contributes up to 10% of the IRM. The iron content of the grain size fractions gives evidence that iron in pedogenically grown remanence carriers does not originate from the detrital iron oxides, but rather from iron-bearing clays and mafic silicates. The contribution of pedogenic magnetite to the bulk IRM increases with the increasing degree of pedogenesis, which depends in turn on climate change.

A simple magnetic mineral identification technique is proposed which measures isothermal remanent magnetisation (IRM) acquired in different field strengths at 293 K and 77 K. Magnetic parameters are introduced that use these IRMs in order to distinguish concentration and type of ferromagnetic minerals in different magnetic states. The method determines easily contributions of superparamagnetic ferrimagnetic minerals in environmental magnetism studies. In addition, high coercivity goethite and possibly superparamagnetic hematite are identified. The analysis of the magnetic properties of a soil profile on a Late Pleistocene terrace from the Jarama river in central Spain is given as an example.

A refined pedostratigraphic scheme in the western Black sea region is proposed on the basis of paleopedological reconstructions coupled with magnetic susceptibility, and other rock magnetic parameters, and Mossbauer spectroscopy. The new scheme matches well with oxygen isotope stages despite local variations in erosion/deposition, strong welding of paleosols and subtle discrepancies in the position of the Matuyama/Brunhes boundary. These limitations are reduced by optimizing resolution of magnetic cycles and paleosol identification. Two humid/warm maxima during the Quaternary are found in pedocomplex PK4 at about 0.5 Ma (corresponding to oxygen isotope stages 13 and 15), and in pedocomplex PK8 related to the Jaramillo subchron. Comparison with the oxygen isotope curve shows that the apparent major driving force of regional soil/loess cyclicity is the 100 ka eccentricity period.

Two sections on the Chinese Loess Plateau (CLP) at Lingtai and Baoji have been investigated to obtain detailed information about the exact stratigraphic position and the recording quality of the Matuyama/Brunhes geomagnetic polarity boundary (MBB). The continuously sampled MBB occurs in the glacial period loess layer L8 in both sections at a similar profile depth indicating comparable average sedimentation rates of about 8 cm/kyr. This stratigraphic position has been recognized in many previous Chinese loess studies and contrasts with observations in marine sediments where this polarity transition is found at the beginning of interglacial oxygen isotope stage 19. The directional patterns of the characteristic remanent magnetization (ChRM) of the two transitional loess records are inconsistent and even depend on the demagnetization technique used to isolate the ChRM. The MBB records also differ significantly from those obtained from the loess section at Weinan and at ODP site 792A near Japan. The VGP paths recorded in loess are not well defined, switch polarity several times and do not prefer specific longitudinal bands. It is suggested that the loess MBB transitional records do not reflect geomagnetic field variations directly, but are the result of a complicated magnetization lock-in mechanism. By comparison with the astronomically-tuned prediction, this process has been delayed in the loess sediment column by 1.5 to 2 m corresponding to about 25'000 yr after deposition.

Most rock magnetometers measure the bulk remanent magnetization of 1-inch cylindrical samples (centimeter scale) or even larger volumes of drill cores. High- Tc superconducting quantum interference device (SQUID) magnetometers are able to measure magnetic fields on rock surfaces at higher resolution on a millimeter scale: the fields of discrete rock-forming magnetic mineral grains or fine magnetic rock textures and structures can be observed when scanning across selected surface areas. The stability problems of a commercially available high- Tc SQUID magnetometer have largely been solved by improving the magnetic shielding and reducing the noise due to turbulent boiling of liquid nitrogen. Magnetizations as weak as 5×10−4 A/m can now be discriminated with a resolution of 1 mm. A software package has been developed to eliminate measurement errors arising from instrumental drift. The program also calculates the downwards continuation of the field data and offers full inversion for the vertical magnetization component. A synthetic sample demonstrates the performance of the SQUID sensor and the inversion software. The potential of high-resolution magnetic imaging is shown by measuring three rock samples with very different magnetic properties.

The 10Be flux onto a loess plateau is composed of two different components: the atmospheric flux and the dust flux. A simple 10Be-susceptibility model shows that the magnetic susceptibility flux can be also divided into a dust related component and an in situ produced pedogenic component. From comparison with the dust 10Be flux, we can separate and quantify the detrital (FD′) and the pedogenic (FX) magnetite contributions to the total magnetic flux (FS). FX/FS varies between 0% and 80% with low values in loess layers and high values in palaeosols and weathered loess. The pedogenic magnetic susceptibility flux could be considered to be linearly related to palaeoprecipitation and may be used as a quantitative measure for regional palaeorainfall in the Chinese loess plateau.

Typical loess-palaeosol formations in the southern part of the Russian plain (Novaya Etuliya type section), in China and in Central Asia show the same pattern of magnetic susceptibility (MS) variations with enhanced signatures in soils compared to loesses. This behavior is well known to be caused by in situ forming fine grained magnetite (maghemite) of pedogenic origin. A different pattern of MS changes has been reported for Western Siberia and Alaska: high magnetic signatures in loesses and low ones in palaeosols. The highest MS values in the Belovo type section (Ob River) are connected with the sand and silt fractions and hence are due to sedimentary processes and terrigenous magnetic minerals. Low MS in palaeosols is related to gleisation. A more complex behaviour of ms changes is observed in the Precaucasus loess section at Otkaznoe. The palaeosols here show enhanced magnetic signatures whereas the loess horizons display largely variable magnetic signals due to changing detrital material influx.

The approximately 50-m thick loess/palaeosol sequence at Paks brickyard (Hungary) was deposited largely during the Brunhes normal polarity chron and its magnetic properties resemble those of similar sections in Europe, Central Asia and China. In order to get information on the grain size dependence of some of the magnetic parameters, two loess and two palaeosol samples were separated into a number of grain size fractions. The separation method employs consecutive sedimentation and centrifugation steps performed on bulk samples suspended in water and diluted with Calgon. Ten grain size fractions were obtained, ranging from 50 μm down to 10 nm. Several magnetic parameters of the different grain size fractions have been measured, at room temperature (low field susceptibility, hysteresis parameters) and at low temperature (susceptibility and thermoremanent magnetisation). They show a strong grain size dependence for the ferromagnetic minerals. Low temperature measurements allow discrimination of the paramagnetic vs. the ferromagnetic signal and give information on the grain size distribution of the very fine ferromagnetic minerals and on the mineral types carrying the magnetic signal. Strong relationships between weathering processes, destruction of paramagnetic minerals and possibly iron-hydroxides, and enhancement of the ferromagnetic signal are observed.

Paleomagnetic and rock magnetic investigations were undertaken on samples from 14 formations in an attempt to examine the tectonic history of south China and to evaluate competing hypotheses for the amalgamation of the Huanan and Yangtze Blocks. The vast majority of the sampled sites were remagnetized; however, results from the Lower Triassic Xikou Formation appear to have escaped remagnetization. The sites pass a fold test and are in good agreement with other results published by Gilder et al. [Gilder, S., Coe, R.S., Wu, H., Kuang, G., Zhao, X., Wu, Q., 1995. Triassic paleomagnetic data from south China and their bearing on the tectonic evolution of the western circum-Pacific region. Earth Planet. Sci. Lett. 131, 269–287]. From the data, however, it is difficult to constrain the hemisphere of these sites during the Early Triassic and as such, a firm resolution of the competing hypotheses cannot yet be offered.

The loess mantle of the VIII Dniestre terrace at Roxolany in the Black Sea area of Ukraine is subdivided into six units, which encompass the following palaeosol taxons: pedocomplexes (PK) with evidence for several soil-forming and sedimentary episodes; incipient monogenetic palaeosols; and horizons of carbonate concretions. These cyclical loess-palaeosol units provide a depositional record from the end of the Matuyama chron through the Holocene. The detailed pedosedimentary subdivision of loesses at Roxolany is generally consistent with magnetic susceptibility depth functions and seems to reflect global climatic variations. Earlier chronologies [Guidebook of the International Geological Congress. XXVII Session, 1984] are re-estimated on the basis of a revised position of the Matuyama–Brunhes boundary and by detailed rock magnetic and micromorphological studies. The strongly developed chernosem of PK 4 at approximately 22 m depth, showing features of rubefication and the highest magnetic susceptibility value, is viewed as a good stratigraphic marker of the Late Cromerian and seems to represent the climatic optimum of the Brunhes chron (oxygen isotope stage 13?). The uppermost PK 2 is represented in the lower part by a chernosem analogous to surface soils of the area and is argued to be no younger than the Last Interglacial (oxygen isotope stage 5e). The poor preservation of PK 2 seems to result from processes of soil degradation and deflation at the time of interglacial–glacial transition. The closely spaced palaeosols between PK 2 and PK 4 seem to relate to three independent interglacials. Highest resolution of the palaeoclimatic record is found at the final Matuyama chron from PK 9 to PK 8 and in incipient soils that contain either humic horizons with enhanced magnetic susceptibility or only horizons of large carbonate concretions.

Saturation magnetization and saturation remanence of 139 loess and paleosol samples from Tajikistan, China and Hungary increase linearly with low field susceptibility in all sections investigated. Thus magnetic enhancement is caused by increasing quantities of ferrimagnetic minerals. The observed variations of high field susceptibility χh are attributed to variations in the amount of clay minerals as χh is linearly correlated with the < 2 µm grain size mineral fraction. The magnetic enhancement process is compared with a theoretical mixing model based on two magnetic mineral assemblages with different but invariable coercivities. The two-component model provides a good approximation to the data from Hungary and the magnetically enhanced paleosol samples in Tajikistan and China. Discrepancies between model calculation and data arise in the behaviour of the loess samples in Tajikistan. Here a three-component model improves the agreement between data and mixing calculation. The magnetic enhancement in the loess in Tajikistan (and China) is different from the one in the paleosols and the link between paleoclimate and susceptibility is not as straightforward as in the Hungarian loess-paleosol sequence.

Isothermal remanent magnetization (IRM) acquisition and alternating field (A.F.) demagnetization analyses were performed on human heart, spleen and liver samples resected from cadavers. The magnetic properties of the samples were measured both at 77K and at 273K. A.F. demagnetization was performed at 273K. Results from the analyses of the tissue indicate the presence of ferromagnetic, fine-grained, magnetically interacting particles which, due primarily to magnetic properties, are thought to be magnetite and/or maghemite. The presence of superparamagnetic particles can be inferred from the increase in saturation IRM values when measured at 77K compared with measurements at 273K and the decay of remanent magnetization upon warming from 77K. The concentration of magnetic material (assuming it is magnetite or maghemite) in the samples varies from 13.7 ng g-1 to 343 ng g-1, with the heart tissue generally having the highest concentration. The presence of magnetic material in these organs may have implications for the function of biogenic magnetite in the human body.

77 paleomagnetic samples from the Upper Silurian reddish limestone and marlstone of the Shan-Thai-Malay block near Baoshan ( 99.1°E, 24.8°N ), western Yunnan, China, reveal a pre-folding remnant magnetization, with a mean direction of D=49.6°, I= −3.2°, k=9.7, a95=5.5°, corresponding a paleopole at 207.0°E, 36.8°N. These results, unlike the upper Paleozoic data with steeper inclinations published earlier, suggest that the block was located at equatorial latitude during late Silurian time, probably adjacent to the northern margin of Gondwanaland.

We have studied 454 oriented samples from seven loess outcrops in the Czech Republic for comparison and correlation of the magnetic properties with those of the loess profiles in China and Central Asia. Three sections at Sedlec (Prague), Zeměchy and Dolni Věstonice cover the time span of the last glacial-interglacial cycle. Loess from the middle Pleistocene period including pedocomplexes V and VI was studied at Sedlesovice (Znojmo) and Karlstejn. Loess of uncertain — possibly lower to middle Pleistocene age — was sampled at Sedlec near Mikulov. At Cervený Kopec (Red Hill, Brno) we investigated the oldest loess near the Matuyama/Brunhes (M/B) boundary. The characteristic remanence (ChRM) determined after magnetic clearning is of normal polarity throughout all sections except at Cervený Kopec. There, two polarity changes from reversed to normal were found within two sections initially thought to represent two successive stratigraphic intervals. However, the marked similarities between lithological, susceptibility, declination and inclination profiles lead us to suggest that the two polarity changes are in fact one and the same. The two sections are therefore laterally equivalent and both have recorded the M/B field reversal. The susceptibility variations were used to mutually correlate the Czech sections and to construct a composite profile across the present day loess outcrops in the Czech Republic. They also serve as a paleoclimate proxy which can be compared and correlated with the paleoclimatic records observed in the Chinese and Central Asian loess. The origin of the low field susceptibility variations was studied by measuring the frequency dependence of susceptibility which revealed that the enhancement within the pedocomplexes is controlled by the amount of fine-grained ferromagnetic minerals present.

Samples of metallurgical dusts and fly ashes from coal power plants and iron works in Upper Silesia as well as soil profiles in the close vicinity of these plants and in Ojcow National Park (ca. 25 km east of the industrial area) have been studied magnetically and mineralogically. The metallurgical dusts and fly ashes are highly enriched in ferromagnetic minerals. The topsoils from profiles collected near the plants have very high values of magnetic susceptibility while susceptibility in the fermentation and humic subhorizons in soil profiles from Ojcow National Park is considerably increased. The magnetic properties of the metallurgical dusts and fly ashes such as frequency dependence of susceptibility, saturation remanence or coercivity are similar to those observed in the top horizons of the soils. They are mostly related to the occurrence of large (multidomain) grains of non-stoichiometric magnetite ranging from 1 to 20 µm. The similarity of the magnetic particles in the soils is taken as evidence of an anthropogenic origin. They are responsible for the high soil susceptibilities in Upper Silesia and in adjacent areas. Some of the magnetic particles carry substantial quantitities of trace elements such as Pb, Ni, Zn and Cu. Field and laboratory susceptibility measurements can therefore be used as a simple and costeffective method of detecting the presence of heavy metals in the soils of this area.

A paleomagnetic record of geomagnetic secular variation during the last 3500 yr has been obtained from three lake sediment cores from lake Aslikul in the western Pre-Ural region (Russia). Pollen data provide a time-scale and relative paleotemperatures which can be compared with radiocarbon dated paleotemperature data for this region. Magnetic susceptibility measurements have been used for correlation between cores and reconstruction of composite core data. The paleosecular variations which have been recorded in the lake Aslikul sediments are consistent with results from West-European lakes. Westward shifting inclination features are observed between the more western European and the Pre-Ural regions which have apparent age differences between 200 and 600 years resulting in drift rates which are of the order of 0.1 degrees/year.

Samples were collected for paleomagnetic analysis from 36 sites from six formations west of the Red River Fault in southwestern Yunnan Province, China on the Simao block (23.4°N, 100.8°E) in an attempt to examine the effects of the India-Asia collision on the Asian continent. Paleomagnetic results from rocks ranging from Cretaceous to Miocene in age indicate a large clockwise rotation of these sites with respect to stable Eurasia since the Late Cretaceous. The tectonic-corrected data from Cretaceous samples (mean direction of two formations) are D = 112.6°, I = 34.7°, α95 = 7.5°, k = 9.1, n = 45, for Eocene samples the data are D = 84.7°, I = 38.9°, α95 = 7.6°, k = 12.0, n = 32, and for Miocene samples they are D = 21.1°, I = 35.5°, α95 = 7.1°, k = 15.3, n = 29. The samples from the Paleocene and Pliocene are either remagnetized or too weak to provide stable directions. The Cretaceous sites were sampled from folded beds and these sites pass the fold test. The amount of rotation seen in this study (R = 86.1 ± 9.9° as a mean value for the Cretaceous, R = 76.8 ± 11° for the Eocene, and R = 14.7 ± 10.0° for the Miocene) is significantly larger than that documented in previous studies from the Lower Cretaceous of northwestern and central Yunnan Province and may indicate that differential rotation has taken place in the region. This rotation can be explained by the northward motion and collision of India with Asia in the Paleocene, which caused continuous deformation of southwestern China in the form of strike-slip faulting and clockwise rotation. It is concluded that the rotation and deformation resulting from this collision probably continued from the Paleocene until at least the Miocene.

Continuous marine sediments of Permian to Triassic age are widely distributed over large areas in Southern China. They offer the potential for developing magnetostratigraphic columns to investigate the polarity status of the palaeomagnetic field. Three carbonate sections on the Yangtze platform, which represent mainly the Upper Permian but also parts of the Lower Triassic and possibly parts of the uppermost Lower Permian, contain a long-term main R-N-R-N-R polarity succession throughout the Permian. This signal is hidden under strong overprint magnetizations of variable origin and can be mostly obtained only from directional trends of the natural remanent magnetization during demagnetization rather than from clear stable end-point directions. The new Chinese polarity sequences are in accord with magnetostratigraphic records from the former USSR and Pakistan. Depending on stratigraphic assignment of the lithological formations studied, either they include the boundary between the Lower and Upper Permian and give evidence that the Kiaman reversed polarity superchron had ended before the Upper Permian, or the formations all belong stratigraphically to the Upper Permian, with the oldest reversed interval to be correlated with the reversed zone in the Midian stage of the palaeontologically well-dated Nammal section in Pakistan. This zone is preceded by at least one normal polarity zone at Nammal so that the end of the Kiaman superchron would not be observed in the new Chinese sections.

The Nabon basin is part of several Miocene intermontane basins related to Andean uplift, continental arc formation and coeval deformation during subduction of the Nazca plate under the South American continent. The basin sequence consists of fluvial, alluvial fan, lacustrine, and pyroclastic mass-flow deposits corresponding with intereruptive and syneruptive stages of basin-fill history. Combined zircon fission-track and palaeomagnetic measurements suggest that the series lies within the 4r chron (ca. 8.5–7.9 Ma). It overlies unconformably the ignimbrite basement dated at ca. 26-19 Ma. Synsedimentary tectonic deformation in the basin is manifested by a master reverse fault along the western margin, differential basement block uplift and related sedimentary bedding geometries such as cumulative sedimentary wedges. The spatial orientation of the tectonic and sedimentary features indicates that the basin underwent WNW-ESE maximal shortening during the fill stage. The short-lived sediment-fill history may be explained, either by subduction-related contractional pulses also recognized in the Peruvian and Colombian Andes or, by the particular position of the basin in the central axial part near the weak fault of a regional translational system.

Magnetic analyses of hippocampal material from deceased normal and epileptic subjects, and from the surgically removed epileptogenic zone of a living patient have been carried out. All had magnetic characteristics similar to those reported for other parts of the brain [6]. These characteristics along with low temperature analysis indicate that the magnetic material is present in a wide range of grain sizes. The low temperature analysis also revealed the presence of magnetite through manifestation of its low temperature transition. The wide range of grain sizes is similar to magnetite produced extracellularly by the GS15 strain of bacteria and unlike that found in magnetotactic bacteria MV-1, which has a restricted grain size range. Optical microscopy of slices revealed rare 5–10 micron clusters of finer opaque particles, which were demonstrated with Magnetic Force Microscopy to be magnetic. One of these was shown with EDAX to contain All, Ca, Fe, and K, with approximate weight percentages of 55, 19, 19, and 5, respectively.

Quaternary deposits in the overdeepened Wehntal, Switzerland, were investigated using both seismic profiling and the analysis of 93.6 m long drill core using sedimentology, geochemistry, palynology, magnetic properties, and luminescence dating. The sediments reveal evidence for two glacial advances that reached the area during Marine Isotope Stage (MIS) 6. The first advance (∼185 ka) may have carved out the basin or at least removed the entire previous Quaternary sediment filling. This first advance likely reached far beyond the limit of the maximum of the Last Glaciation. The second advance (∼140 ka) was of smaller extent, possibly of cold-based nature, and likely reached only slightly beyond the limits of the Last Glaciation.