bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depositional processes and basin analysis of Messinian evaporites in Cyprus
Authors: Robertson A.H.F. , Eaton S. , Follows E.J. , Payne A.S. 
Published: July 2007

ABSTRACTMessinian evaporites in Cyprus resulted from the interplay of Mediterranean‐wide and eustatic sea‐level changes and local tectonics, in an inferred above‐subduction zone setting. Distinctive Tortonian‐early Messinian pre‐evaporitic facies include diatomaceous marls and microbial carbonates, overlain by a variety of gypsum facies and then by lagoonal‐lacustrine deposits and local palaeosols. Facies analysis and comparisons allow construction of a simple model, in which evaporites formed in semi‐isolated small basins not far below global eustatic sea‐level. Coarsely crystalline gypsum formedin situ along the margins of small basins and within shallow‐water lagoons (< 10 m deep); this comprised common banded‐stacked (i.e. layered) selenite, swallowtail selenite, botryoidal selenite and sugary‐bedded selenite. Fine‐grained gypsum precipitated widely and was reworked into basinal areas (< 70 m deep) by weak traction currents and low‐density turbidity currents. Shallow‐water derived selenite was also reworked basinwards by high‐density turbidity currents and debris flows. Slumps indicate tectonic instability. More detailed basin analysis can be achieved by study of individual sub‐basins. In the Polemi sub‐basin in the west, a Lower Unit (up to 60 m thick) comprises basinal gypsum, interbedded with gypsum turbidites and mass flow deposits, with slumps. This is overlain by an extensive mega‐rudite (up to 20 m thick) including up to metre‐sized clasts of marginal gypsum facies. Above, the Upper Unit (up to 70 m thick) includes shallow‐water gypsum (e.g. swallowtails), marl and minor microbial carbonates. The Pissouri sub‐basin in the south‐west exposes marginal facies of the Upper Unit, including deltaic elastics and palaeosols. The Maroni sub‐basin in the south exhibits a basinal lower gypsum unit, with laterally equivalent marginal facies (up to 50 m thick), overlain by an extensive mega‐rudite (up to 20 m thick). Finally, the Mesaoria subbasin in the north exposes relatively marginal gypsum facies in an unstable tectonic setting. Formation of the Polemi, Pissouri and Mesaoria gypsum sub‐basins relates to coeval extensional faulting and graben development. Evaporites in south Cyprus (Maroni sub‐basin) formed in elongate basins between former compressional lineaments created by localized Early Miocene thrusting. In the sub‐basins of west, south‐west and south Cyprus, large‐scale slumping of marginal gypsum facies took place towards depocentres (to form megarudite debris flows), triggered by one or several phases of extensional faulting.
Eratosthenes Seamount: collisional processes in the easternmost Mediterranean in relation to the Plio‐Quaternary uplift of southern Cyprus
Authors: Robertson A.H.F. , Kidd R.B. , Ivanov M.K. , Limonov A.F. , Woodside J. M. , Galindo‐Zaldivar J. , Nieto L. 
Published: July 2007

ABSTRACTImportant new light is shed on subduction and incipient collisional processes in the Easternmost Mediterranean, notably the Plio‐Quaternary uplift of the Troodos ophiolite, from new geophysical information collected during a cruise of the R.V. Gelendzhik in July 1993, as part of the Training‐through‐Research' programme. The data collected over the Eratosthenes Seamount formed part of the site‐survey work for Leg 160 of the Ocean Drilling Program scheduled for spring 1995. The main results are that the Eratosthenes Seamount is in the process of actively subsiding, breaking‐up and being thrust, beneath both Cyprus to the north and the Levantine Basin to the south. Northwards thrusting appears to post‐date the Messinian, when evaporites accumulated around the lower flanks of a pre‐existing seamount feature. Comparison with the geology of southern Cyprus and offshore areas suggests a causative link between northward underthrusting of the Eratosthenes Seamount and late Pliocene‐mid Quaternary uplift of southern Cyprus, focused on the centre of the Troodos ophiolite.
Late Pliocene‐early Pleistocene Athalassa Formation, north central Cyprus: carbonate sand bodies in a shallow seaway between two emerging landmasses
Authors: McCallum J.E. , Robertson A.H.F. 
Published: July 2007

ABSTRACTThe late Pliocene‐early Pleistocene Athalassa Formation accumulated within the Neogene Mesaoria basin of northern Cyprus, bordered by two subdued, but rising, landmasses, the Kyrenia Range to the north and the Troodos ophiolitic massif to the south. In the eastern part of the basin, the formation is dominated by cross‐stratified bioclastic‐rich sandstones interpreted as shallow‐marine, carbonate sand bodies. The sediments are described in terms of six calcarenite facies and subfacies and one sandstone fades. Palaeocurrent analysis indicates that the carbonate sand bodies formed near the southern margin of the Kyrenia landmass and then migrated southwards across a shallow‐marine platform. The driving force is believed to have been storms, generated by strong winds. Such winds during the late Pliocene‐early Quaternary were probably stronger than today in this area. Other factors influencing deposition of the formation include minor tectonic instability, and probable eustatic sea‐level changes. Study of the Athalassa Formation thus provides insights into late Pliocene‐Pleistocene palaeoenvironments in the easternmost Mediterranean.
Structural relationship between the Sea of Marmara Basin and the North Anatolian Fault Zone
Authors: Ergün Mustafa , Özel Erdeniz 
Published: July 2007

ABSTRACTThe North Anatolian Fault (NAF) zone is 1500 km long, extending almost up to the Greek mainland in the west. It is a seismically active right‐lateral strike‐slip fault that accommodates the relative motion between the Turkish block and Black Sea plate. The Sea of Marmara lies along the western part of the NAF and shows evidence of subsidence. In this area pure strike‐slip motion of the fault zone changes into extensional strike‐slip movement that is responsible for the creation of the Sea of Marmara and the North Aegean basins. The northern half of the Sea of Marmara is interpreted as a large pull‐apart basin. This basin is subdivided into three smaller basins separated by strike‐slip fault segments of uplifted blocks NE‐SW. Basinal areas are covered by horizontally layered sedimentary sequences. Uplifted blocks have undergone compressional stress. All the blocks are subsiding and are undergoing vertical motions and rotations relative to one another. The uplifted blocks exhibit positive Bouguer gravity anomalies. According to gravity interpretation, there is relative crustal thinning under the Sea of Marmara. The northern side of the Sea of Marmara is marked by a distinctive deep‐rooted magnetic anomaly, which is dissected and shifted southward by strike‐slip faulting. The southern shelf areas of the Sea of Marmara are dominated by short‐wavelength magnetic anomalies of shallow origin.
Glaukǒpis ‐ an examination of the relationship between geological laws and literary creation
Authors: Luzi Mario 
Published: July 2007

ABSTRACTThe present paper is an examination of the relationship between man and the great marine depths, starting from the earliest known myths up to our present‐day conception based on scientific evidence. The concept of the abyss and the horror it inspires are investigated from a philosophical and poetic point of view to emphasize the vital importance of such concept in human life.
Plate tectonics in Russia
Authors: Khain Victor E. 
Published: July 2007

ABSTRACTAfter a short period of propagation of Wegener's continental drift ideas in Russia in the twenties and first half of the thirties of this century, there came a much longer period (1935–1960) of fixist reaction', when vertical tectonic movements were regarded as primary and most important and horizontal ones as secondary and subsidiary. In the sixties, interest in the manifestation of horizontal movements on strike‐slip faults, overthrusts and nappe formation began to grow, and at the verge of sixties and seventies ideas of plate tectonics began to penetrate into Russia. But at the begining they met strong resistance mainly from the older generation of scientists. In spite of this, these ideas finally gained the support of the majority of Earth scientists in this country. Russian geologists and geophysicists made a significant contribution to the development of the plate tectonics theory as well as in its regional, global and theoretical aspects.
Deformational features of the Ustica volcanic island in the Southern Tyrrhenian Sea (Italy)
Authors: de Vita Sandro , Guzzetta Giuseppe , Orsi Giovanni 
Published: July 2007

ABSTRACTMacro‐ and meso‐structural analyses of the Ustica rock formations lead to an interpretation of most of the deformational features that define the structural framework of the island. A regime of sinistral transtension seems to be the best explanation for the most significant fault associations. This regime is consistent with the kinematic model for the Tyrrhenian back‐arc‐accretionary wedge system proposed by Doglioni (1991). A caldera collapse in the northern part of the island provides the major source of volcanotectonic deformation while cracks, open or filled by clastic and/or volcanic material, were formed by downslope block sliding mostly along the southern coastline. Joints in indurated surge deposits were generated by brittle deformations induced by gravity after deposition, rather than by tectonism.
Elemental and stable isotope variations in the Cretaceous–Tertiary boundary sediments from the Soča Valley, NW Slovenia
Authors: Dolenec T. , Pavšič J. 
Published: July 2007

ABSTRACTOxygen and carbon stable isotopes and 25 elements were determined in the undisturbed K/T boundary profile of a flysch succession in the Soča Valley, Slovenia. The elemental enrichment and stable isotope anomalies are not confined strictly to the biostratigraphically defined K/T boundary. The relatively weak metal enrichment, which is probably due to the high sedimentation rate at the time of deposition of the K/T transition sequence, was found in a clayey layer and in the boundary clayey mar] 15 cm and 5 cm above the boundary, while the negative shift in δ18O and δ13C of carbonates was restricted to the basal part of the boundary clayey marl, approximately 5 cm below the boundary. It is postulated that elemental and isotopic anomalies are probably related to the supposed, so far poorly investigated impact of an extraterrestrial body in the Gorski Kotar area of Croatia.
Mitigative Anthropogeomorphology: a revived ‘plan’ for the Mediterranean Sea Basin and the Sahara
Authors: Cathcart Richard Brook 
Published: July 2007

ABSTRACTSince at least 1964 macro‐engineering has proposed solutions for Earth‐biosphere problems affecting mankind and its infrastructures. From 1929–1948 Herman Sorgel put forth his ‘Atlantropa Macroproject, which was designed to lower the Mediterranean Sea by 1 m every year by natural evaporation and to irrigate the Sahara with diverted Zaire River freshwater. The present author has slightly modernized Sorgel's gift toHomo sapiens.Construction of ‘Atlantropa’ would provide Macro‐engineering and Terraforming with a much‐needed practice run for the remaking of our Solar System's planets.
Crust and upper mantle models along the active Tyrrhenian rim
Authors: Marson I. , Panza G.F. , Suhadolc P. 
Published: July 2007

ABSTRACTThe volcanic complexes from the Eolian islands to the Campania/Roman regions and Tuscany further north, rest on lithospheric sectors which overlie the Adriatic continental lithosphere sinking along the Apennine‐Maghrebian orogenic belt. Evidence for this stems from the melting, at mantle depth, of upper crustal materials as indicated by the widespread interaction of S‐type and K‐alkaline melts. The genesis of atypical magmas of the Roman Province (central‐southern Italy) appears to be the result of an important block faulting and deep lithospheric rifting of the Apennine continental margin lying parallel to and above relic sinking slabs. Intermediate and deep‐focus earthquakes indicate that the lithospheric slab is still seismically active under the Eolian‐Calabrian area and, sporadically, at the southern end of Campania. On the other hand, in the Roman/Tuscan region, it seems to be almost inactive, few earthquakes having been located with hypocentral depths not exceeding 150 km. The analysis of the spectral content of seismic sources supports the existence of two distinct zones of lithospheric shortening in correspondence of Tuscany and South Tyrrhenian sea, which are separated by a tensional region, which extends from Latium to Calabria. The existence of distinct lithospheric slabs along the Tyrrhenian rim is supported by surface wave dispersion and scattering measurements as well as P‐wave residuals, and is confirmed by the trend of long‐wavelength gravity anomalies. Bidimensional gravity models along transects in the Tyrrhenian sea and italian peninsula interpreted within the geometrical constraints imposed by the results of the interpretation of aeromagnetic, seismic and seismological data have been used to delimit the spatial distribution of the density contrasts in the upper mantle which might be due to the existence of the above‐mentioned lithospheric slabs.
Pan African layered diorite‐tonalite‐granodiorite from Sinai massif: an open system fractionation at a subduction zone
Authors: El‐Metwally Ahmed A. , Ibrahim Mohmed E. 
Published: July 2007

ABSTRACTThis paper reports on the occurrence of layered Pan African dioritetonalite‐granodiorite (DTG) rocks. The layering is marked by alternation of melanocratic (M) layers (diorites and tonalites) and leucocratic (L) layers (tonalites and granodiorites). M‐samples have cumulus biotite+hornblende+relict pyroxene+plagioclase+K‐feldspars+magnetite+apatite, and have transitional calc‐alkaline and metaluminous affinities. They were derived from subduction‐related magma enriched in Rb, Ba, K and LREE and depleted in Sr and Nb. L‐samples have cumulus plagioclase+hornblende. They are enriched in Sr and depleted in Rb, Ba, K, Nb and LREE. They have calc‐alkaline and peraluminous affinites.The formation of the rhythmic layers of DTG composition can be attributed to periodical replenishment of pulses of basic magma into a more evolved acidic magma chamber under open system conditions. Field relations, mineralogy and element concentration among the M‐ and L‐layers indicate that at the subduction zone, the ascending magma was contaminated with lower crustal materials (marginal basin metasediments) which led to LILE‐enrichment, Nb‐depletion and transition from calc‐alkaline to alkaline and from metaluminous to peraluminous affinities as well.
Detecting a sequence boundary across different tectonic domains: an example from the middle Miocene of the northern Apennines (Italy)
Authors: Amorosi A. , Colalongo M.L. , Vaiani S.C. 
Published: July 2007

ABSTRACTSequence stratigraphic concepts can provide a powerful tool for understanding the tectono‐sedimentary evolution of areas extending across different tectonic domains. An example is provided by the upper Serravallian strata of the northern Apennines, where a sedimentological and biostratigraphic study allows a sequence boundary to be traced across the foredeep and piggy‐back basin successions. Turbidite sedimentation of predominantly alpine and subordinate apenninic provenance occurred in the apenninic foreland basin throughout the middle Miocene. Deep‐water sedimentation in the foredeep was laterally associated with deposition in shelf to slope environments in the piggy‐back basins.In the piggy‐back basin succession, the upper Serravallian sequence boundary is a laterally extensive unconformity within homogeneous marly deposits. This unconfonnity is laterally correlative with the base of lenticular turbidite bodies. A stratigraphic lacuna affecting Zone N14 characterizes the marginal areas, where glaucony‐rich deposits assigned to Zone N15 unconformably overlie marls displaying association of Zone N13. In the depocentres, where no significant stratigraphic gap has been detected, the sequence boundary is narrowly constrained to lowermost Zone N14.The upper Serravallian unconformity of the piggy‐back basins succession is correlative with time‐equivalent features in two distinct parts (inner basin and outer basin) of the foredeep. In the inner basin the sequence boundary separates basin margin turbidites from overlying slope hemipelagites. In a more external position (outer basin) the sequence boundary is the base of a characteristic mega turbidite of apenninic provenance (Turrito layer). In other sectors of the outer basin, where turbidite sedimentation was entirely of alpine provenance, the sequence boundary has no clear physical expression.The observed facies distribution in the study area suggests that an important thrusting event affected the northern Apennines in the late Serravallian, resulting in submarine channel incision and nondeposition in the piggy‐back basins. Compressional activity in the foredeep was responsible for the closure of the inner basin and subsequent shifting of turbidite sedimentation in the outer basin. Slope instability led to widespread remobilization of previously deposited turbidites, triggering turbidite events of huge volume. The different characteristics of the sequence boundary in the various parts of the foredeep constitute an example of differential response of a multisourced supply system to tectonic deformation.
The Eotvos force revisited
Authors: Gasperid M. , Chierici F. 
Published: July 2007

ABSTRACTThe Eotvos acceleration, too low to be the principal driving force in Wegener's theory of continental drift, where the decoupling surface was placed between crust and mantle, must be re‐evaluated in the context of Plate Tectonics, where the same surface is localized at the lithosphere‐asthenosphere boundary. In this note, taking into account the departure from spherical symmetry of the Earths internal gravitational potential, a value for the Eotvos acceleration is obtained that is one order of magnitude larger than pre‐Plate Tectonics estimates and almost two times greater than more recent results. This force was higher in the geological past because the Earths angular velocity and flattening were greater than today, and thus may be considered in the large‐scale reconstruction of continental displacements.
Active thrust tectonics in western Sicily (southern Italy): the 1968 Belice earthquake sequence
Authors: Monaco Carmelo , Mazzoli Stefano , Tortorici Luigi 
Published: July 2007

ABSTRACTThe 1968 Belice earthquake sequence, characterized by six main shocks with 5 < M < 5.4, represents the strongest seismic event recorded in western Sicily in historical times. The epicentral area is located in the Belice Valley, a region lacking any topographic lineament likely to result from a fault with significant offsets of any kind. Instrumental data show that hypocentres of the major shocks are distributed along a roughly N‐dipping plane extending from about 36 km to 1 km depth. Fault plane solutions show pure thrusting mechanisms on N‐dipping, ENE‐trending planes, or oblique slip with a right‐lateral component of motion along steep WSW‐dipping planes, both as a result of approximate N‐S shortening. The observed destruction indicates that isoseismal areas are elongated in an ENE direction. Similarly, the epiccntral distribution of events with M ≥ 4 outlines a roughly elliptical ENE‐elongated area located 20 km NW of the Sciacca‐Rocca Ficuzza thrust front. This ENE‐striking structure, representing the regional morphotectonic feature closest to the epicentral area, consists of two main imbricate fan systems. In the southernmost system, Quaternary deposits (tentatively dated as 1.0–0.7 Myr old) are involved in a large ramp anticline uplifting them to a maximum altitude of 346 m. The occurrence of Holocene lacustrine piggy‐back basins on the rear of this structure also indicates late Quaternary activity of the underlying thrust. Seismological, structural and morphotectonic observations suggest that multiple ruptures might have occurred during the 1968 sequence on a blind crustal thrust ramp located beneath the epicentral area. Slip propagated southwards along the shallow ramp‐flat system characterizing the thin‐skinned foreland fold and thrust belt of southwestern Sicily, being dispersed in flexural folding processes and diffuse strain along this path.
Seismogeological effects and macroseismic fields
Authors: Tertulliani Andrea 
Published: July 2007

ABSTRACTSeveral seismogeological effects of earthquakes on the environment have been collected by means of the ING macroseismic procedure. The fast and easy collection of information about ground and hydrological effects constitutes a complementary instrument in assessing the effects on human structures and the environment, and, ultimately, establishing intensity values. In this paper the distribution of seismogeological effects within intensity values has been verified, using data from three moderate Italian earthquakes; the density of the same effects are then discussed in comparison with isoseismal maps.
Ancient synsedimentary structural control on thrust ramp development: an example from the Northern Apennines, Italy
Authors: Tavarnelli Enrico 
Published: July 2007

ABSTRACTThe Umbria‐Marche‐Sabina foreland fold and thrust belt (Northern Apennines, Italy) provides excellent test‐cases for the hypothesis of ancient syndepositional structural features controlling thrust ramp development. The sedimentary cover, Late Triassic to Miocene in age, is made of platform and pelagic carbonates, whose deposition was controlled by significant synsedimentary extension. Normal faulting, mainly during the Jurassic and the Late Cretaceous‐Palaeogene, determined sensible lateral thickness variations within the relative sequences. By late Miocene the sedimentary cover was detached from its basement along a mainly evaporitic horizon, and was deformed by means of eastward‐verging folds and thrusts.In order to locate the points where thrust ramps branch‐off the basal detachment, both line‐length and equal‐area techniques were used in the construction of a balanced cross‐section through three major fault‐related folds in southeastern Umbria. The nucleation of thrust ramps was controlled by the occurrence of Jurassic and Cretaceous‐Palaeogene synsedimentary normal faults. These interrupted the lateral continuity of the evaporitic unit (the Late Triassic Anidriti di Burano Fm.) at the base of the sedimentary cover, and acted as obstacles to the eastward propagation of the thrust system, giving rise to major folds which originated from tip‐line folding processes.Therefore, the inferred relationships between ancient normal faults and late thrusts indicate that synsedimentary tectonic structures and the related lateral stratigraphic variations can be envisaged as mechanically important perturbations, which effectively control the nucleation and development of thrust ramps.