bluuebunny/crossref_metadata_2025 huggingface dataset:
The bottom of the ocean: three abysses
Authors: Nievo Stanislao
Published: July 2007

This testimony is the result – better, the tale – of some sea and ocean descents made by a novelist to gather information for writing two of his books. The first one is The meadow under the sea published by Mondadori, 1974, and thereafter in various other editions, in Italian and other languages. The second is The Blue Whale, Mondadori, 1988, which went through several Italian editions.

The present piece concerns impressions and events of contacts with the marine and oceanic floor in the Mediterranean sea, along Atlantic beaches and the Indian Ocean, off Tromelin, Madagascar.

The last voyage takes the novelist to a peculiar situation, where water's darkness overturns the image, comes through the bathysphere port‐hole and the observer looks inside himself, a view that corresponds to a mythical history of the ocean floor.
Two revolutions in the Earth Sciences
Authors: Emiliani Cesare
Published: July 2007

Two great revolutions have shaken the field of the geological sciences since World War II, one involving the solid Earth and the other involving the ice ages. The former came after a long and gradual preparation that extended across a century. The latter came abruptly, after a long period of stasis during which little conceptually new had emerged. The former did not demolish anything ‐ it was only the logical conclusion of a long process of discovery. The latter demolished a canon that had become a dogma held true for half a century. The reactions of the scientists to the two revolutions are a study in contrast: instant acceptance of the former versus laggard and reluctant acceptance of the latter.
Plate tectonics at Lamont: the first year‐1966
Authors: Pitman Walter , Bonatti E. , Wezel F. C.
Published: July 2007

During the period from the mid 1950s to the 1960s it seemed as if the community of earth scientists was slowly being dragged toward accepting continental drift. But resistance was often steadfast. Each new ideal or set of data produced a trickle of new converts, but also generated heated debate. The concept of sea‐floor spreading and the corollary hypothesis that the process of spreading would generate a set of symmetrical magnetic anomalies was particularly disputatious. The discovery of the Eltanin 19 magnetic anomaly profile ended the dispute and the trickle became a flood.
Definition and global correlation of the Santonian‐Campanian boundary
Authors: Gale A.S. , Montgomery P. , Kennedy W.J. , Hancock J.M. , Burnett J.A. , McArthur J.M.
Published: July 2007

Review of biostratigraphical evidence from different regions shows that criteria used by workers on various marine fossil groups to define the Santonian‐Campanian boundary differ considerably in relative age and position. Probably the most widely recognizable of these criteria is the extinction of the distinctive crinoid Marsupites testudinarius (North America, Europe, Asia, north Africa, Australia), which, coincides exactly with two separate definitions of the boundary ‐ appearances of the ammonite Placenticeras bidorsatum and the belemnite Gonioteuthis granulataquadrata ‐ and may also coincide with a third ‐ entry of the planktic foraminiferan Globotruncana elevata. A comparison of evidence from upper Santonian and lower Campanian successions in widely separated regions allows us to place a series of important biostratigraphical markers in correct order. Defining the boundary at the extinction of M. testudinarius corresponds to a 87Sr/86Sr of 0.707479, and a small positive excursion in δ13C. The base of magnetochron 33R, generally considered to coincide with, or fall just above the base of the Campanian, is shown to lie within the upper Santonian Uintacrinus socialis Zone.
Holocene soil chronoassociation in part of the Middle Gangetic Plain: morphological and micromorphological characteristics
Authors: Mohindra Rakesh
Published: July 2007

Systematic variations in soil characteristics related to degree of soil profile development in part of the Middle Gangetic Plain suggest a soil chronoassociation similar to the soil chronosequences observed on some river terrace formed by tectonic uplift. This chronoassociation has five members QG1 to QG5, the youngest being QG1 (< 500 yr BP). Variations in degree of horizon differentiation, profile thickness, clay accumulation, plasma separation, argillan thickness, weathering stage and day mineralogy have been used to determine the degree of soil development.

Pedogenic processes active in these soils are decalcification, translocation of clay, sesquioxide and organic matter, plasma separation and weathering of minerals. The amount and variability of clay minerals are significantly related to the type and duration of pedogenesis in different parts of the area. The oldest soils with pedogenic calcite (10 000 yr BP) developed during a dry period. Since 8000 yr BP climatic conditions of higher rainfall and better drainage have prevailed in the area.

Neotectonic movements have tilted the Gandak megafan block and have caused shifting of the Gandak river to the east about 105 km from its original course, leaving behind numerous channels, ponds, lakes and other features of impeded drainage.
Alkali feldspars as a main phosphorus reservoirs in rare‐metal granites: three examples from the Bohemian Massif (Czech Republic)
Authors: Frýda J. , Breiter K.
Published: July 2007

Phosphorus‐rich alkali feldspars were found in three peraluminous highly differentiated albite‐topaz‐Li‐mica granites in the W and S parts of the Bohemian Massif. The average contents of P2O5 in K‐feldspars (Křížovy kámen 0.57 wt%, Homolka 0.77 wt%, and Podlesí 0.83 wt%) are higher than the average contents of P2O5 in albites (Křížovy kámen 0.23 wt%, Homolka 0.23 wt%, and Podlesí 0.39 wt%). The analyses of feldspars indicate that partition coefficient of phosphorus between K‐feldspar and albite range from 1.5 to 2.5. Measured data in K‐feldspars suggest a statistically significant difference from the Al3++P5+=2 Si4+ substitution mechanism for higher phosphorus concentration. The P‐content in K‐feldspars from the Podlesí‐granite represent the highest P‐content in natural feldspar known to date (up to 2.5 wt% of P2O5)‐ It is suggested that all studied granites retained nearly all phosphorus of granitic melts and that their alkali feldspars represent major reservoirs of phosphorus.
Determination of uranium, thorium and potassium contents in rock and soil samples using low‐energy gamma ray spectrometry
Authors: Reddy A. Subjender , Rao N. Venkat
Published: July 2007

A low‐energy gamma ray spectrometric set‐up for determination of uranium, thorium and potassium in rock and soil samples is described. The procedure described exploits the fact that a large proportion of gamma quanta produced in the Th and U decay series have energies of less than 1 MeV. The instrumental parameters such as sensitivity and detection limits for the low‐energy region have been studied. The measuring conditions were optimized by suitably minimizing the background and by increasing the overall sensitivity with the help of proper geometry of measurement and sample parameters. High sensitivity and low detection limits for U and Th can be achieved using low‐energy gamma ray spectrometry. The method provides a rapid analysis with a counting time of the order of a few minutes for each sample.
A high‐velocity layer in the lower crust of the North German Basin
Authors: Rabbel W. , Förste K. , Schulze A. , Bittner R. , Röhl J. , Reichert J.C.
Published: July 2007

A network of deep seismic refraction profiles in Northern Germany consisting of parts of the European Geotraverse (EGT) and additional new Unes is interpreted. The most striking result is the proof of an approximately 10 km thick high‐velocity layer in the lower crust. Its P‐wave velocity of 6.9‐7.5 km s−1 is typical for shield crusts or lower crust in extensional environments intruded by mafic magma. The layer is observed in an area of roughly 150 × 180 km north of the Elbe river and seems to continue north‐east, at least up to the Caledonian deformation front at the southern edge of the Ringkøbing‐Fyn High. It correlates spatially with an area of high positive gravity anomalies. Here, a Moho topography of several kilometres, which had already been postulated on the basis of gravity inversions and sporadic near‐vertical PMP reflections, could be confirmed by the interpretation of seismic wide‐angle records. The termination of the high‐velocity lower crust at the Lower Elbe Lineament, which strikes parallel to the Teisseyre‐Tornquist Zone, contributes to its definition as a major lineament in the context of central European tectonics.
Optical parameters of maturity of organic matter dispersed in sediments: first results from the Central Apennines (Italy)
Authors: Corrado Sveva
Published: July 2007

Levels of organic maturity of Mesozoic and Tertiary sequences outcropping in the Central Apennines have been established, using vitrinite reflectance techniques, the Thermal Alteration Index and fluorescence colours of organic matter dispersed in sediments. These results provide new constraints throughout the Meso‐Cenozoic evolution of this crustal sector. In exploration geology, vitrinite reflectance provides data on hydrocarbon maturation by constraining organic matter maturity. In sedimentary basin modelling, it is adopted to define the palaeothermal regime. Vitrinite reflectance (Ro) also provides information on the burial history of sedimentary basins and may be employed to estimate tectonic uplift and erosion rates. Thermal Alteration Index (TAI) and fluorescence colour values can be correlated with Ro and may be used to estimate the degree of maturation when vitrinite is absent.

Samples derived from the Sabini and Tiburtini Mts, in slope facies between the Latium–Abruzzi carbonate Platform and the Umbria–Marche pelagic Basin; from the Simbruini and Ernici Mts, in carbonate Platform facies, and from upper Miocene turbiditic deposits outcropping between the Olevano–Antrodoco Une, towards the West, and the Marsica slope facies, towards the East. Both the pre‐terrigenous Meso‐Cenozoic sequences show a low grade of organic maturity: the Sabini and Tiburtini Mts show Ro values that are less than 0.4%, and the Simbruini–Ernici Range show Ro values that range between 0.5% and 0.65%. Field analysis indicates that the cause of these low maturity levels is that thick sequences of turbidites were never deposited during the Neogene evolution of the Apennine thrust belt. Moreover, Upper Miocene turbiditic deposits also show low maturity levels, with Ro values that are less than 0.5%, indicating that these deposits were never overthrusted by huge volumes of rocks, during the chain building. The slight increase in the maturity level recorded in the Marsica area may be related to local heating along shear zones in areas of strike‐slip tectonics.
Estimating the carbon transfer between the ocean, atmosphere and the terrestrial biosphere since the last glacial maximum
Authors: Maslin M.A. , Adams J. , Thomas E. , Faure H. , Haines‐Young R.
Published: July 2007

Carbon dioxide records from polar ice cores and marine ocean sediments indicate that the last glacial maximum (LGM) atmosphere CO2 content was 80–90 ppm lower than the mid‐Holocene. This represents a transfer of over 160 GtC into the atmosphere since the LGM. Palaeovegetation studies suggest that up to 1350 GtC was transferred from the oceans to the terrestrial biosphere at the end of the last glacial. Evidence from carbon isotopes in deep sea sediments, however, indicates a smaller shift of between 400 and 700 GtC. To understand the functioning of the carbon cycle this apparent discrepancy needs to be resolved. Thus, older data have been reassessed, new data provided and the potential errors of both methods estimated. New estimates of the expansion of terrestrial biomass between the LGM and mid‐Holocene are 700 GtC ± > 300 GtC, using the ocean carbon isotope‐based method, compared with of 1100 GtC ± > 500 GtC using the palaeovegetation estimate. If these estimates of the carbon shift to the terrestrial biosphere are equilibrated with the dissolved carbon in the oceans, and the CaCO3 compensation of the ocean is taken into account, then the glacial atmospheric CO2 would have been between 50 (± 30) ppm and 95 (± 50) ppm higher. The glacial atmosphere therefore should have had a CO2 partial pressure of between 330 and 375 μatm. Hence, a rise of between 130 and 175 μatm in atmospheric CO2, rather than 80 μatm, at the end of the last glacial must be accounted for.
Application of the chlorine‐36 method for the characterization of the groundwater circulation in tectonically active areas: examples from northwestern Anatolia/Turkey
Authors: Balderer W. , Synal H.‐A.
Published: July 2007

For groundwaters of tectonic active regions the problem of determining the residence time above the range of the tritium method arises. The usually applied isotope techniques are often not appropriate because of (i) the high amount of water‐rock interaction, (ii) the underground production of nuclides in crystalline fissured rocks under geothermal conditions, (iii) the occurrence of highly saline waters at boiling temperature affected by waterrock interaction processes, as also the high fluxes of CO2. However, the 36Cl evolution will be affected by these processes, too. Nevertheless it gives an independent tool to investigate the groundwater evolution. Therefore the application of the 36Cl method looks very promising. Within this publication the interpretation of 36Cl measurements of three study areas along the North Anatolian Fault zone (from East to West) of Kuzuluk/Adapazari, Bursa and of Canakkale (Tuzla/Kestanbol) are discussed. By considering for each area the sources of 36Cl and the water‐rock interaction with respect to the chloride cycle, information on the ongoing processes of groundwater circulation and evolution have been derived. In addition, ranges of residence times of these waters were gained which are compatible with the results of geological, hydrogeological and hydrochemical investigations (Balderer et al., 1991; Greber, 1992, 1994; lmbach, 1992, 1994; Imbach and Balderer, 1990; Mutzenberg, 1989) as well as with already developed conceptual groundwater flow models.
Long‐term (105) or short‐term (103) δ13C excursion near the Palaeocene‐Eocene transition: evidence from the Tethys
Authors: Lu Gangyi , Keller Gerta , Adatte Thierry , Ortiz Nieves , Molina Eustoquio
Published: July 2007

Expanded sedimentary records from the Tethys reveal unique faunal and isotopic changes across the Palaeocene‐Eocene (P‐E) transition. Unlike in the open oceans, the Tethys exhibits a gradual decrease of 1.5% in δ13C values prior to the rapid δ13C excursion. Associated with the 613C excursion is a decrease in calcite burial, increase in detrital content and appearance of a unique opportunistic planktic foraminifera1 assemblage (e.g. compressed acarininids). The existence of a prelude decrease in δ13C values in the Tethys suggests that the P‐E δ13C excursion may have occurred in two steps and over a few hundred thousand years, rather than as one step over a few thousand years as previously suggested. This slower excursion rate is readily explained by changing organic carbon weathering or burial rates and avoids the need of invoking ad hoc scenarios.
Field examples of variations in fault patterns at different scales
Authors: Peacock D.C.P.
Published: July 2007

Three field examples are presented which show changes in fault patterns at different scales. Normal faults in Jurassic limestones in Somerset consist of zones of sub‐parallel segments at the exposure‐scale, but contain complex zones of brecciation at the decimetre‐scale. Normal faults in chalk at Flamborough Head consist of a complex network of small faults which accommodate strain between a set of large faults. The different‐sized faults at Flamborough Head have different geometries and histories, with the larger faults showing a phase of reverse reactivation. The faulting in the Sydney Basin, Australia, can be explained in terms of the evolution and reactivation of transfer zones between overstepping faults. These transfer zones can cause the deformation to appear to be more complex as the analysis becomes more detailed.

Much recent work on the scaling relationslups of faults assumes that self‐similar fault patterns occur over a wide range of scales. The data presented in this paper, however, suggest that there are problems in using the deformation pattern at one scale to infer deformation at other scales. Ideally, any analysis should involve the study of a wide range of scales to overcome these problems.
Syn‐metamorphic nappe complex in the Rhodope Massif. Structure and kinematics
Authors: Burg Jean‐Pierre , Ricou Luc‐Emmanuel , Ivano Zivko , Godfriaux Ivan , Dimov Dimo , Klain Laslo
Published: July 2007

Mylonitic gneisses of the Bulgarian and Greek Rhodope were deformed under medium pressure‐type metamorphism. The kinematic information contained in these gneisses shows that shear‐deformation occurred during development of a nappe complex. Lithologies and metamorphic histories allow a lower (footwall) and an upper (hanging wall) terrane to be distinguished that define a crustal‐scale duplex. As oceanic crust is involved, collision between two continental units with subsequent crustal thickening is inferred. The blocks would be Moesia to the north, and the Lower‐Rhodope promontory to the south, which collided in the Mesozoic to early Cenozoic. The nappe complex is characterized by south to southwestward (foreland directed) piling‐up and is associated with both coeval and subsequent extension. The late extension is associated with the establishment of a high temperature‐low pressure metamorphic gradient and plutonism that predates, but makes a transition to, the lithospheric extension of the Aegean Arc.
Seismic anisotropy of the crystalline crust: what does it tell us?
Authors: Rabbel Wolfgang , Mooney Walter D.
Published: July 2007

The study of the directional dependence of seismic velocities (seismic anisotropy) promises more refined insight into mineral composition and physical properties of the crystalline crust than conventional deep seismic refraction or reflection profiles providing average values of P‐and S‐wave velocities. The alignment of specific minerals by ductile rock deformation, for instance, causes specific types of seismic anisotropy which can be identified by appropriate field measurements.

Vice versa, the determination of anisotropy can help to discriminate between different rock candidates in the deep crust. Seismic field measurements at the Continental Deep Drilling Site (KTB, S Germany) are shown as an example that anisotropy has to be considered in crustal studies. At the KTB, the dependence of seismic velocity on the direction of wave propagation in situ was found to be compatible with the texture, composition and fracture density of drilled crustal rocks.
Local site effects in the northern North Sea based on single‐station spectral ratios of OBS recordings
Authors: Atakan Kuwet , Havskov Lens
Published: July 2007

In recent years, there has been a growing awareness of the importance of local site effects in earthquake damage. A number of studies of recent destructive earthquakes have illustrated the relative contribution of enhanced ground shaking due to unconsolidated sediment layers.

Among the different methods used to estimate local site response, the spectral ratio of shaking at a sedimentary site with respect to a bedrock reference site, has been successfuly applied in different geological environments. In this study, a technique recently proposed by Nakamura (1989) is used to evaluate site response using spectral ratios of horizontal vs. vertical components of earthquake recordings from a temporary ocean bottom seismograph (OBS) network in the northern North Sea and a permanent OBS at Oseberg oil field. Comparison with results obtained from the standard spectral ratios, indicate that the method is applicable also to subsea conditions, and the estimates obtained in this study indicate similar amplification factors to those obtained previously from analytical techniques. The ambient noise data on the other hand, gave unstable results, probably due to different noise characteristics in the marine environment. The results obtained on the earthquake data, however, provide an encouraging alternative to previously used analytical techniques for estimating local site response.
The Amirante ridge/trough complex: response to rotational transform rift/drift between Seychelles and Madagascar
Authors: Plummer Ph. S.
Published: July 2007

The Amirante ridge/trough complex developed along the Late Cretaceous transform boundary that separated the Seychelles/India and Madagascar/Somali Basin plates. Motion between these plates was complex, comprising sinistral N‐S strike‐slip movement coupled and coeval with counter‐clockwise rotation induced when seafloor spreading developed in only the southern portion of the transform. The overall morphology of the complex comprises a series of arcuate ridge and trough segments. These segments were successively produced by tectonic and volcanic activity within the zone of migrating plate contact adjacent to the rotational pivot where compression was replaced by extension along the transform boundary. In the extensional regime to the south of this contact zone the Mascarene oceanic basin developed, whilst in the compressional zone further north island arcs developed and the ophiolites of Baluchistan were obducted from the Somali Basin onto the leading edge of the Seychelles/India plate.
Field, petrophysical and carbon isotope studies on the Lapland Granulite Belt: implications for deep continental crust
Authors: Korja T. , Tuisku P. , Pernu T. , Karhu J.
Published: July 2007

The Palaeoproterozoic Lapland Granulite Belt is a seismically reflective and electrically conductive sequence of deep crustal (6–9 kbar) rocks in the northern Fennoscandian Shield. It is composed of garnet‐sillimanite gneisses (khondalites) and pyroxene granulites (enderbites) which in certain thrust sheets form about 500 m thick interlayers. The structure was formed by the intrusion of intermediate to basic magmas into turbiditic sedimentary rocks under granulite facies metamorphism accompanied by shearing of the deep crust about 1.93–1.90 Gyr ago (Gal. Granulites were upthrust 1.90–1.87 Ga and the belt was divided by crustal scale duplexing into four structural units whose layered structure was preserved. The thrust structures are recognized by the repetition of lithological ensembles and by discordant structural patterns well distinguishable in airborne magnetic and electromagnetic data. Thrusting gave rise to clockwise pressure‐temperature evolution of the belt. However, some basic rocks possibly record an isobaric cooling path. The low bulk resistivity of the belt (200–1000 Ωm) is caused by interconnected graphite and subordinate sulphides in shear zones. On the basis of carbon isotope ratios this graphite is derived mostly from sedimentary organic carbon. The seismic reflectivity of the belt may be caused by velocity and density differences between pyroxene granulites and khondalites, as well as by shear zones.
The significance of Messinian occurrences of Globorotalia margaritae and Globorotalia puncticulata in Sicily
Authors: Butler R.W.H. , Pedle H.M. , Maniscalco R. , Grasso M. , McClelland E. , Finegan B.
Published: July 2007

Globorotalia puncticulata and Globorotalia margaritae are critical species that define internationally recognized planktonic foraminiferal biozones in the Pliocene. These biozones are defined from stratotype sections on Sicily and their fauna are commonly considered to have been introduced to the Mediterranean after an influx of Atlantic water that terminated the late Miocene desiccation of the basin. Herein new discoveries of these species in rocks that predate the late Miocene desiccation are described. These data are supported by magneto‐ and lithostratigraphy that have been integrated at a single continuous section. Not only do these discoveries question the existing foraminiferal biozone stratigraphy, they also suggest new models for the dispersal of planktonic species. It is proposed that Globorotalia puncticulata and perhaps even Globorotalia margaritae evolved in the Mediterranean during earliest Messinian times (during or before chron C3Bn1n) and dispersed into the Atlantic. This suggests that a marine connection remained between the two sea areas until at least chron C3An.1n. Using the existing geomagnetic polarity time scale, these occurrences are some 2 Myr earlier than previously recorded in the Mediterranean. The distribution of G. margaritae and G. puncticulata in Mediterranean sections is likely to reflect palaeoenvironment or the preservation of deposits rather than the absolute age of the sediments.
Revision of the earthquake catalogue and seismicity of Croatia, 1908–1992
Authors: Herak Marijan , Herak Davorka , Markušić Snježana
Published: July 2007

The paper presents the results of Croatian earthquake catalogue revision for the period 1908–1992. The revised catalogue lists a total of 4853 events (4486 after 1908), of which 3700 are mainshocks. All primary data sources available to us (seismograms, phase onset time readings, macroseismic questionnaires…) were consulted in order to improve the quality and reliability of magnitude, intensity and location. Along with the most important earthquake parameters the catalogue contains entries that enable assessment of the reliability of location and bibliographic references. Using the temporal analysis of the maximum‐likelihood estimate of the b‐value in the frequency‐magnitude relation, the catalogue is estimated to be complete for events with M ≥ 4.0 throughout the investigated period. The magnitude completeness threshold decreases to 3.8 after the middle of the century, and to about 3.6 in the last three decades. It is noted that the b‐value variation with time is closely tied to the seismic activity, as well as that at present there seems to be a lack of seismic energy release corresponding to the M = 6.0–6.5 earthquake.
Electronic Publishing: The issues and ways forward
Authors: Whaler Kathy
Published: July 2007

On 10 April 1995, during the EUG 8 meeting in Strasbourg, about 100 people gathered to participate in a Forum on Electronic Publishing, organized by Dominic Vaughan (Elsevier Science) and Kathy Whaler (University of Edinburgh and Royal Astronomical Society). In what follows, I have tried to convey a flavour of the style of the various presentations, as well as their content. Many points were reiterated by more than one speaker; in general, I have not repeated them.
Tectono‐magmatic control on vertical dip slip basement faulting: An example from the Fennoscandian Shield
Authors: Heeremans M. , Stel H. , van der Beek P. , Lankreijer A.
Published: July 2007

Vertical dip‐slip basement faults play an important role in the evolution and structuring of the Earth's crust. The Proterozoic anorogenic rapakivi‐anorthosite setting of the Fennoscandian Shield in southern Finland exhibits a widespread pattern of vertical dip‐slip basement faults that are deeply eroded. The Porkkala‐Mantsala (PM)‐fault, located c. 30 km W of Helsinki is part of a system of crustal lineaments that closely follows the outcrop pattern of Mid‐Late Proterozoic anorogenic crustal elements, such as basic dyke swarms, the outline of rapakivi granites and remnants of sediment‐filled grabens. These lineaments are formed by low‐grade dip‐slip faults that overprint Svecofennian shear zones. Structural analysis of the PM‐fault supports an interpretation in terms of reactivation of a high‐grade ductile wrench zone. Successive stages of brittle deformation visible in as well the PM‐fault and the Obbnäs granite demonstrate that brittle deformation in the PM‐fault is coeval with the intrusion of the anorogenic Obbnäs rapakivi granite. Based on the spatial and temporal relationship of anorogenic magmatism and block faulting, a genetic relationship is proposed.
A consistent map of the postglacial uplift of Fennoscandia
Authors: Ekman Martin
Published: July 2007

A consistent map of the recent postglacial rebound of Fennoscandia is constructed on the basis of sea‐level records, lake‐level records and repeated high‐precision levellings.

The uplift rates calculated from the sea‐level series form a consistent framework of the map. The sea‐level stations used are 56 reliable stations in the Baltic Sea and adjacent waters with series spanning 60 years or more, many of them about 100 years. Using a reference station in the Baltic Sea and another one outside the Baltic, all results are reduced to a common time span, the 100‐year‐period 1892–1991, in order to eliminate oceanographic changes. Inland, uplift differences are obtained from the repeated national levellings and, in four of the large lakes, from long water level series in pairs. The levellings, however, yield less accurate land uplift values than the sea‐level and lake‐level data.

The resultant map shows a fairly smooth phenomenon, with a maximum apparent uplift in the Gulf of Bothnia of 9.0 mm yr‐1. The standard error is typically 0.2 mm yr‐I close to the sea level stations, larger inland.

Finally the pattern of the present uplift as determined here is observed to be very similar to that of the past uplift as determined from ancient shore‐lines of the Litorina Sea. However, the ratio between the past uplift and the present uplift rate tends to increase somewhat towards the uplift centre. This might reflect a non‐uniform mantle viscosity. Also, the uplift maximum seems to have migrated towards NNE.
The Bälinge conglomerate in northern Sweden reinterpreted as a magmatic, hydraulic breccia
Authors: Wikström Anders , Mellqvist Claes , Barbarid Bernard
Published: July 2007

The Bälinge conglomerate has played a key role in the lithostratigraphy of northern Sweden. The conglomerate, with pebbles dominated by granodiorites and tonalites in a generally biotite‐rich matrix, borders volcanic rocks with unclear relative age relationships. In nearby areas these volcanites have been intruded by plutonic rocks (c. 1.9 Ga) which are similar to the pebble material. On these grounds, the conglomerate has been regarded as younger than the volcanic rocks and an important marker in the geological evolution of the region. In this preliminary study, it is suggested that the features displayed by the Balinge conglomerate are not compatible with an epiclastic origin. On the contrary, they indicate that this rock represents a hydraulic breccia where the roundness of the granitoid ‘pebbles’ has resulted from erosion in a fluidised, heterogeneous and magmatic environment. In the actual area the ‘conglomerate’ must thus be dismissed as a stratigraphic marker horizon. It belongs to the early Svecofennian evolution.
Contiguous Laurentia and Baltica before the Grenvillian‐Sveconorwegian orogeny?
Authors: Romer Rolf L.
Published: July 2007

Close geochronological correspondence of Mesoproterozoic extension‐related magmatism and comparable tectonic and geochronological evolution of the Grenville and Svecononvegian orogens suggests that the Laurentian and Baltic Shields could have been joined during the Mesoproterozoic and did not separate until after the Grenvillian‐Sveconorwegian orogeny. The combined Grenville‐Svecononvegian orogen is here interpreted to have formed during the collision of coherent Laurentia‐Baltica with an unknown craton, which is in contrast to earlier explanations that favour a late‐Mesoproterozoic rotation between Laurentia and Baltica followed by collision of these two cratons with each other.
Pre‐Tertiary blueschist terrains in the Hellenides: evidence from detrital minerals of flysch successions
Authors: Faupl P. , Pavlopoulos A. , Wagreich M. , Migiros G.
Published: July 2007

Detrital blue amphiboles detected in flysch sandstones of the Hellenides of mainland Greece give important information on uplift and exhumation history of blueschist terrains. The occurrence of these HP/LT minerals in the terminal flysch of the Pindos zone as well as in the Othrys flysch of the Subpelagonian zone from late Maastrichtian/ Palaeocene time onwards proves a Pre‐Tertiary (Eohellenic) stage of blueschist formation. Detrital blue amphiboles from flysch sequences of the Ionian zone indicate a further pulse of uplift of high‐pressure rocks during the Palaeocene/Eocene. Blueschist rocks of this latter time range are radiometrically well documented in the Hellenides.
Petrology of pumices of April 1993 eruption of Lascar (Atacama, Chile)
Authors: Bernard Déruelle , Oscar Figueroa A. , Eduardo Medina T. , Jose Viramonte G. , Mario Maragaño C.
Published: July 2007

Lascar Volcano (Atacama, Chile) erupted on 18–20 April 1993. Several sub‐Plinian explosions occurred, and some were mushroom‐shaped. The highest column rose up to 23 km. Ash clouds crossed South America eastwards. Dacite pumice falls made of blocks and ashes were deposited on the flanks of the volcano as a result of collapsed columns. The pumice contains phenocrysts of plagioclase, enstatite, augite, biotite, magnetite and ilmenite and small crystals of apatite. The 1992 previous andesite dome inside the crater was destroyed. Banded blocks resulting from mingling of the dacitic pumice and andesite from the dome are found in the pumice flow. Both the lava dome and the pumice are representative of the Lascar high‐K magma unit. Dacitic pumice is a product of crystal fractionation of the andesitic magma.
Permeability and stress in crystalline rocks
Authors: Banks David , Odling Noelle E. , Skarphagen Helge , Rohr‐Torp Erik
Published: July 2007

Groundwater from crystalline rocks is a significant resource in many areas of the world. It is also an important medium for contaminant transport from, for example, deep nuclear waste repositories. Stress distributions in fractured rocks are important in controlling groundwater flow in several ways: (i) palaeostress fields are responsible for the evolution of fracture systems which transmit groundwater; (ii) current in situ stress fields will influence the shape and aperture of fractures; (iii) humans can influence the natural stress field in a rock mass to enhance fracture flows. The significance of stresses for groundwater flow can be investigated by field techniques (hydraulic fracturing), laboratory techniques (stress cells) or by numerical modelling.
Strain localization and large‐scale block rotation in the lower continental crust, Kataragama area, Sri Lanka
Authors: Kleinschrodt Reiner
Published: July 2007

In Sri Lanka a suite of rocks is regionally exposed which once formed a part of the middle to lower crust of a collisional orogen with about doubled crustal thickness. A subhorizontal to gently west‐dipping major thrust zone (Highland Basal Thrust) crosses Sri Lanka from NNE to SSW. It separates a granulite facies upper unit, the Highland Complex from an amphibolite facies lower unit, the Vijayan Complex with a displacement of more than 300 km. The basal Highland Complex was migmatized during thrusting. Rheological contrasts between dry granulites and migmatites were high in the presence of partial melts. Granulite facies fragments within the migmatites vary from the decimetre to kilometre scale. Granulites in the area of Kataragama, formerly interpreted as the Kataragama Klippe, are now identified as a large‐scale raft within the migmatites, which is completely separated from the overriding Highland Complex. During thrusting strain was concentrated in the migmatized basal parts of the Highland Complex. After crystallization of the migmatites thrusting continued, and strain was still localized within the migmatites. Therefore, granulite facies parageneses, structures and textures are preserved in the granulite rafts. The deviation of the granulite facies structures in the Kataragama raft from the general trend in the Highland Complex is interpreted to indicate counterclockwise rotation of the whole raft by about 90° around a subvertical rotation axis.
Seasonally ice free glacial nordic seas without deep water ventilation
Authors: Seidov Dan , Mastin Mark
Published: July 2007

At present the Nordic Seas are a key region of North Atlantic Deep Water (NADW) formation. Two alternative scenarios have been suggested by some authors for the Last Glacial Maximum: (i) the Nordic Seas were permanently covered by sea ice, preventing the formation of NADW, or (ii) that they were seasonally free of ice and that deep water formation did occur. A modified scenario is presented here based on parallel ocean circulation modelling results from the GFDL primitive equation model and a planetary geostrophic model. It is suggested that the glacial Nordic Seas were at least seasonally ice free, but it is observed that there was never deep water formation from the surface; rather it occurred only in the North Atlantic south of 40°–50°N. North of 40°N, the weaker LGM northward flowing thermohaline conveyor is subducted below a reverse conveyor which occurred to a depth of over 1000 m. Various modelling experiments presented here indicate that the reversed conveyor was primarily caused by the colder conditions of the glacial North Atlantic that led to far stronger zonality of glacial analogue of the North Atlantic Current.
Near‐K/T age of clastic deposits from Texas to Brazil: impact, volcanism and/or sea‐level lowstand?
Authors: Keller Gerta , Stinnesbeck Wolfgang
Published: July 2007

Near‐K/T boundary clastic deposits from Texas, Mexico, Haiti, Guatemala and Brazil, often described as impact‐generated tsunami deposits, are stratigraphically below well‐defined K/T boundary horizons and appear not to be causally related to the K/T boundary event. Stratigraphic evidence indicates that their deposition began during the last 170–200 kyr of the Maastrichtian, coincident with a major eustatic sea‐level lowstand that lowered sea level by as much as 70–100 m. Clastic deposition ended a few tens of thousands of years before the K/T boundary during a rapidly rising sea level. The presence of glass in clastic deposits in Haiti, northeastern Mexico and Yucatan suggests that the sea‐level lowstand coincided with a time of major volcanism or pre‐K/T boundary bolide impact.
A review of studies of the earliest glaciation of Iceland
Authors: Geirsdóttir Áslaug , Eiriksson Jón
Published: July 2007

Glaciers and volcanoes have been the trademark of Iceland for centuries. The glaciers now cover ≅10% of the country and the volcanic regions are covered by lava flows every 5–10 kyr on average. Naturalists have concentrated on these two aspects, making notes on volcanic eruptions and traveling along the glacier margins ever since the first settlement of Iceland in the ninth century in some of the earliest episodes of geological research. Systematic studies of the glaciers began in the latter half of the 18th century. Even earlier, features such as striations and moraines were discovered and described in locations remote from the contemporary glacier margins. These features were interpreted as the effect of a much more extensive ice sheet on the island. At the beginning of the 20th century the discussion of the origin of sediments was unseparable from the age problem. From 1910 to 1950 very few new data were presented on the glaciation history of Iceland. A few sporadic publications either accepted or rejected previous conclusions. Systematic geological mapping of the country started in the wake of World War II encouraged by the acceptance of the plate tectonic theory in the late sixties. One of the most important results of this revived mapping effort was the identification of interbedded sediments interpreted as glacial deposits. Around 1975 Iceland was known in the geological literature for preserving more numerous glacial deposits than found elsewhere on land in the northern hemisphere. Over the last few years, systematic lithofacies analysis of sediments interbedded within lava flows has been conducted with the aim of delineating the earliest glaciation of Iceland and the periodicity of glaciation through the Tertiary and Quaternary. The results show a gradual growth of ice from south‐east towards the north and west during the Pliocene‐Pleistocene transition interrupted by periods of recessions and intermittent ice‐free conditions.
How detrital mica affects compactional porosity loss?
Authors: Mátyás János
Published: July 2007

Detrital micas are moderately abundant components in lithic sandstones. Examples from the Törtel and Szolnok Formations (Pannonian basin) and from the Lower Freshwater Molasse and Upper Marine Molasse (Swiss Molasse basin) show that the response of micas to increasing effective stress due to burial is substantially different from that of true ductile particles: the mica plates bend, but their thickness remains essentially constant. Based on this observation, a new model is proposed to describe the relationship between porosity loss and the ratio of mica‐thickness and grain size. The results of calculations emphasize the importance of this latter parameter, as opposed to porosity loss from deformation of true ductile grains which is independent of the relationship between the grain sizes of deforming and rigid components.
Artificial radionuclides in the sediments of the Rhǒne river: a snapshot of the situation during winter 1994/95
Authors: Dietrich Dorothee , Medici Fausto
Published: July 2007

Artificial radionuclides (60Co, 106Ru, 134Cs and 137Cs) produced in the nuclear power plants along the Rhǒne valley have been detected in most of the 35 sediment samples collected from the shores of the Rhǒne river in southern France. In one sample traces of 241Am were found, suggesting the presence of transuranic elements. The wide use of river water for irrigation and the occasional big inundations of the Rhǒne have spread the artificial radionuclides over huge areas, quite far behind the river shores. Although artificial radionuclides are present in fields where food crops are collected, their activity is currently considerably lower than the activity of the natural radionuclides present in the river sediment.
The tectonic significance of Italian magmatism: an alternative view to the popular interpretation
Authors: Lavecchia Giusy , Stoppa Francesco
Published: July 2007

The Tyrrhenian rift zone has been the site of widespread magmatism since late Tortonian times. A pronounced asymmetrical distribution, reflecting the tectonic structure, characterizes Italian magmatism. Sodic basalts occur on the western Tyrrhenian flank and transitional‐MORB basalts occur in the Tyrhenian Sea. The eastern flank, however, is characterized by K‐alkaline and HK‐ to ultra‐alkaline (e.g. carbonatites and melilitites) rocks. Major trace elements and isotopic compositions allow two major magmatic lineages to be identified: one relating to a non‐radiogenic basaltic end‐member and the other to a mantle end‐member enriched in Ca, with high LILE/HFSE ratio and high Sr isotopic ratios. Their mantle sources are located within the lithosphere thermal boundary layer (TBL) and the metasomatized phlogopite‐carbonate asthenosphere at the base of the TBL, respectively. The composition and spatial distribution of volcanism and relative mantle sources tend to map the geometry of the lithospheric mantle and to define a pronounced increase in depth from less than 60 km to about 100 km across the boundary between the thinned Tyrrhenian lithosphere and the Adriatic lithosphere. A mechanism of intra‐continental passive rifting, which drives mantle upwelling, is sufficient to satisfy the petrological and geochemical constraints and the observed tectonic environment without requiring a subduction plane.
Sedimentology of the Upper Burdekin River of North Queensland, Australia—an example of a tropical, variable discharge river
Authors: Fielding Christopher R. , Alexander Jan
Published: July 2007

The Burdekin River is an example of a class of tropical streams which experience two to four orders of magnitude variation in discharge, in response to seasonal but erratic monsoonal rainfall. Floods of the Burdekin rise abruptly, reaching peak discharges of up to 40,000 m3 s‐1 in less than 24 h; maintain peak flow for up to a few days, and recede exponentially. The geomorphology and deposits of these rivers reflect the extreme discharge fluctuations, and have not previously been described.

A stretch of the upper Burdekin River comprising four bends and one straight reach was examined near the town of Charters Towers. The river bed is largely exposed for most of any year, with a small, misfit perennial channel carrying low stage flow. Major geomorphic elements of bends include point bars with ridge‐and‐swale topography, three distinct types of chute channels, avalanche slipfaces up to 5 m or more high around the downstream edges of bars, and on the outer part of one point bar an elevated, vegetated ridge. Straight reaches are flat or gently inclined, sand‐ and gravel‐covered surfaces. Much of the river bed is covered by well sorted, in places gravelly, coarse to very coarse‐grained sand with local accumulations of pebble to boulder gravel. Lower parts of the river bed are periodically draped by mud which is desiccated on exposure. Dunes and plane beds are the most commonly occurring bedforms, with local development of gravelly antidunes. Most bank tops and upper, vegetated bars are covered by silt and fine‐grained sand. The river bed also hosts a low‐diversity but locally high‐abundance, flood‐tolerant flora dominated by the paperbark tree Melaleuca argentea, which plays an important role in controlling the distribution of sediment.

The gross geomorphology of the river bed and most of the sedimentary features are interpreted as having formed during major (bankfull or near bankfull) flows, which have a recurrence of about 18 years (based on 65 years hydrographic data). The initial rapid drop in discharge following flood peaks appears to preserve flood peak features on upper bars more or less intact, whereas lower areas are subjected to variable degrees of modification during falling stage and by more frequent, non‐bankfull discharge events.
Thermotectonic evolution of a rifted continental margin: fission track evidence from the Kangerlussuaq area, SE Greenland
Authors: Hansen Kirsten
Published: July 2007

Fission track analyses of apatites from sediments, Precambrian gneisses and Caledonian to Tertiary intrusive rocks from the Kangerlussuaq region reveal its post‐Caledonian thermotectonic history. Inland the history involves cooling to temperatures within the high temperature part of the apatite annealing interval and slow cooling (or reheating) continued in Cretaceous times through this interval. Apatites from coastal areas between Kangerlussuaq and Tasiilaq reveal only Tertiary cooling. In Tertiary times cooling accelerated after the main intrusive phase in the Tertiary. The evolution is taken as evidence for a general uplift/erosion since Caledonian times probably disturbed by basin formation and sedimentation and reheating due to magmatic activity. Thermal subsidence of the rift shoulders following the opening of the adjacent oceanic basin is not indicated. Annealing patterns inland of the plume centre in the Kangerlussuaq provide no evidence for the earlier movement of the plume from a westerly direction.
A geodynamic model of the Southern Apennines accretionary prism
Authors: Doglioni C. , Harabaglia P. , Martinelli G. , Mongelli F. , Zito G.
Published: July 2007

The Apennines comprise a Neogen—Quaternary accretionary prism that shows several anomalies with respect to classic alpine‐type mountain belts, namely (i) low elevation, (ii) a shallow new Moho below the core of the belt, (iii) high heat flow in the internal parts, (iv) mainly sedimentary cover involved in the prism, (v) a deep foredeep and (vi) a fully developed back‐arc basin. The suction exerted by a relatively eastward migrating mantle can determine the eastward retreat of the subduction zone and an asthenospheric wedging at the retreating subduction hinge. Heat flow, geochemical and seismological data support the presence of a hot mantle wedge underlying the western side of the Apenninic accretionary prism. A thermal model of the belt with foreland dipping isotherms fits with deepening of the seismicity toward the east. Mantle volatiles signatures are also widespread in springs along the Apennines.