<p>In subduction zones, the accretionary wedges play a vital role in mediating the burial processes of incoming oceanic sediments and eventually their return pathways to the surface. A direction of the previous tectonic models invoked the standard corner flow theory, assuming a slab-parallel shear and a rigid, fixed overriding plate, to elucidate the crustal recycling processes in tectonic wedges. To deal with more complex subduction-collisional settings, where they have deformable overriding plates, and associate a horizontal slab migration (advance or rollback) component during subduction, we develop a generalized corner flow model to revisit the problem of return flow mechanics, providing a criticality analysis of the return flows as a function of the geometric, kinematic, and rheological conditions in accretionary wedges. A new set of analytical solutions is presented to evaluate the limiting conditions in which a wedge can set in significant return flows, leading to focused exhumation of the deep-crustal materials. The theoretical results suggest that, for moderate wedge-taper angles (<span class="inline-formula">∼30</span>°), the viscosity ratios (<span class="inline-formula"><i>μ</i><sub>r</sub></span>) between the overriding plate and the wedge <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>≥</mo><mo>∼</mo><msup><mn mathvariant="normal">10</mn><mn mathvariant="normal">3</mn></msup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="37pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="a56e87bfc11b706d2a8d6ced5b59cfa9"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="se-17-573-2026-ie00001.svg" width="37pt" height="14pt" src="se-17-573-2026-ie00001.png"/></svg:svg></span></span> provide favourable tectonic settings for the return flow kinematics in accretionary wedges. Decrease in <span class="inline-formula"><i>μ</i><sub>r</sub></span>, or addition of slab roll back weakens the return flows, whereas slab advance greatly strengthens the return flows. The analytical solutions are also utilized to demonstrate reversals in the shear-sense patterns across the wedge. We expand this study by incorporating results from scaled laboratory experiments to evaluate applicability of the generalized theoretical model. It is shown from the theoretical model that the total pressure in the accretionary wedge dynamics becomes close to the lithostatic value when the rheological setting has low-viscosity (10<span class="inline-formula"><sup>19</sup></span> Pa s) wedge materials.</p>
Salvatore Giammanco, Vincenza Maiolino, Andrea Ursino
et al.
This work presents the results of an integrated monitoring of soil radon gas and seismic activity at Mt. Etna from August 2023 to May 2025, aimed at enhancing comprehension of magma migration and eruption dynamics. Radon data were collected using a permanent station with an alpha particle probe, aggregated hourly. The INGV-OE network monitored seismic activity at 100 Hz; volcanic tremor was analyzed using Root-Mean-Square (RMS) values from the Serra La Nave station. Earthquakes were located using the Hypoellipse algorithm and a 1D crustal velocity model. A robust correlation was found between radon and RMS anomalies, with the former preceding the latter with increasing probability over time (e.g., 30.1% within 1 day, 46.4% within 3 days). Correlations were also found between radon anomalies and Strombolian activity at the summit craters (e.g., 23.8% within 1 day for the Central Crater), suggesting a potential predictive role for radon. Conversely, correlations with paroxysmal events were weaker in the short term but increased over longer time windows. No clear correlation was found between radon anomalies and seismic strain release, likely due to differing temporal resolutions. These results support the idea that radon plays a role as a short-term precursor in volcanic unrest.
<p>Passive seismic data were acquired together with active seismic data along a 2.8 km long profile in the Sudret area of Gotland, Sweden, as part of a feasibility study for storage of CO<span class="inline-formula"><sub>2</sub></span> below the Baltic Sea. Seismic interferometry using cross-correlation and cross-coherence was employed on the passive seismic data. Cross-correlation was used to retrieve virtual shot gathers containing mainly surface waves, while cross-coherence was used to retrieve mainly seismic reflections. Inversion for shear wave velocity and CDP processing of the passive data result in velocity profiles and images that correlate well with borehole data, synthetic seismograms and active seismic data acquired at the site. Interpretations of the passive surface wave and body wave results provide geological information which complement the active data results, the surface waves providing S-wave velocity information and the body waves providing an image that may have better signal quality at deeper levels. Results from the active seismic and passive seismic data correlate well and there is no indication of any large-scale faults in the area. Furthermore, analysis of the frequency and direction of the ambient noise using power spectral density and beam forming show that ocean waves and human activity around the island of Gotland make the Sudret area an ideal location for passive imaging through ambient noise interferometry. Our results illustrate that passive seismic imaging can be an important complement to active seismic data for structural studies of the subsurface with respect to CO<span class="inline-formula"><sub>2</sub></span> storage and monitoring in the Gotland area, Sweden, and perhaps elsewhere.</p>
<p>Plate coupling plays a fundamental role in the way in which seismic energy is released during the seismic cycle. This process includes quasi-instantaneous release during megathrust earthquakes and long-term creep. Both mechanisms can coexist in a given subduction margin, defining a seismotectonic segmentation in which seismically active segments are separated by zones where ruptures stop, classified for simplicity as asperities and barrier, respectively. The spatiotemporal stability of this segmentation has been a matter of debate in the seismological community for decades. In this regard, we explore in this paper the potential role of the interaction between geological heterogeneities in the overriding plate and fluids released from the subducting slab towards the subduction channel. As a case study, we take the convergence between the Nazca and South American plates between 18–40° S, given its relatively simple convergence style and the availability of a high-quality instrumental and historical record. We postulate that trans-lithospheric faults striking at a high angle with respect to the trench behave as large fluid sinks that create the appropriate conditions for the development of barriers and promote the growth of highly coupled asperity domains in their periphery. We tested this hypothesis against key short- and long-term observations in the study area (seismological, geodetic, and geological), obtaining consistent results. If the spatial distribution of asperities is controlled by the geology of the overriding plate, seismic risk assessment could be established with better confidence.</p>
Mohammad Firoze Quamar, Jyotsna Dubey, Pooja Tiwari
et al.
We present multiproxy records from a 2.25-m-long lake sediment profile from central India, which suggested that between ~22,200 and 18,658 cal yr BP, the Indian Summer Monsoon (ISM) was weak, supporting open vegetation in a cool and dry climate, which is globally correlated with the Last Glacial Maximum (LGM). The grain size data of this phase suggest low-energy conditions, indicating a weak ISM. Environmental magnetic concentration-dependent parameters also confirm this weakened ISM. Between ~18,658 and 7340 cal yr BP, the ISM underwent a notable increase, and open mixed tropical deciduous forests replaced the existing vegetation under a warm and moderately humid climate. Environmental magnetic parameters and the grain size data signal a shift toward higher energy levels, in harmony with the warm and moderately humid climate during this time span. Between ~7340 and 1960 cal yr BP, the ISM intensity further increased, which supported open mixed tropical deciduous forests with a rise in prominent tree species under a warm and a relatively more humid climate, correlated with the global Holocene Climatic Optimum (HCO). The trends in environmental magnetic parameters and grain size data mirror this phase of climatic amelioration. From ~1961 cal yr BP to the present, the ISM has intensified, giving rise to dense mixed tropical deciduous forests under a warm and relatively more humid climate. Environmental magnetic parameters and the grain size data are in tandem with the palynogical findings from this phase of the ISM variability.
W. M. van der Meij, A. J. A. M. Temme, S. A. Binnie
et al.
<p>Understanding long-term soil and landscape evolution can help us understand
the threats to current-day soils, landscapes and their functions. The
temporal evolution of soils and landscapes can be studied using
geochronometers, such as optically stimulated luminescence (OSL) particle ages or radionuclide inventories.
Also, soil–landscape evolution models (SLEMs) can be used to study the
spatial and temporal evolution of soils and landscapes through numerical
modelling of the processes responsible for the evolution. SLEMs and
geochronometers have been combined in the past, but often these couplings
focus on a single geochronometer, are designed for specific idealized
landscape positions, or do not consider multiple transport processes or
post-depositional mixing processes that can disturb the geochronometers in
sedimentary archives.</p>
<p>We present ChronoLorica, a coupling of the soil–landscape evolution model Lorica
with a geochronological module. The module traces spatiotemporal patterns of
particle ages, analogous to OSL ages, and radionuclide inventories during
the simulations of soil and landscape evolution. The geochronological module
opens rich possibilities for data-based calibration of simulated model
processes, which include natural processes, such as bioturbation and soil
creep, as well as anthropogenic processes, such as tillage. Moreover,
ChronoLorica can be applied to transient landscapes that are subject to
complex, non-linear boundary conditions, such as land use intensification,
and processes of post-depositional disturbance which often result in complex
geo-archives.</p>
<p>In this contribution, we illustrate the model functionality and
applicability by simulating soil and landscape evolution along a
two-dimensional hillslope. We show how the model simulates the development
of the following three geochronometers: OSL particle ages, meteoric <span class="inline-formula"><sup>10</sup></span>Be inventories
and in situ <span class="inline-formula"><sup>10</sup></span>Be inventories. The results are compared with field
observations from comparable landscapes. We also discuss the limitations of
the model and highlight its potential applications in pedogenical,
geomorphological or geological studies.</p>
For proper cave surveying using DistoX, the device needs to be calibrated with adequate accuracy. Calibrating does not require any tools; but, tools to make calibration easier have been developed. Theoretical consideration shows that the use of certain tools enables one to introduce a type of calibration error that goes undetected by the calibration software. In this study, the existence of such errors is experimentally confirmed and their magnitude is estimated. It is demonstrated to be crucial that the DistoX is calibrated and that the calibration is valid, that is, that the device has not changed since it was last calibrated. No part of the DistoX must have moved or changed its magnetization since calibration, not even the battery. The calibration method used and the quality of the resulting calibration are important too. It is highly recommended that the DistoX be checked immediately before surveying a cave and thus avoid the possibility of using an uncalibrated, not validly calibrated, or poorly calibrated device. To complete the check, a few survey shots are measured multiple times with the device at different roll angles, and the back shot of one of the shots is measured. If the device is properly calibrated, the measurements will agree with each other within the acceptable measurement error. This is not the case for a device that is not properly calibrated.
J. Kvapil, J. Plomerová, H. Kampfová Exnerová
et al.
<p>The recent development of ambient noise tomography, in
combination with the increasing number of permanent seismic stations and
dense networks of temporary stations operated during passive seismic
experiments, provides a unique opportunity to build the first
high-resolution 3-D shear wave velocity (<span class="inline-formula"><i>v</i><sub>S</sub></span>) model of the entire
crust of the Bohemian Massif (BM). This paper provides a regional-scale
model of velocity distribution in the BM crust. The velocity model with a
cell size of 22 km is built using a conventional two-step inversion approach from
Rayleigh wave group velocity dispersion curves measured at more than 400
stations. The shear velocities within the upper crust of the BM are
<span class="inline-formula">∼0.2</span> km s<span class="inline-formula"><sup>−1</sup></span> higher than those in its surroundings. The
highest crustal velocities appear in its southern part, the Moldanubian
unit. The Cadomian part of the region has a thinner crust, whereas the crust
assembled, or tectonically transformed in the Variscan period, is thicker.
The sharp Moho discontinuity preserves traces of its dynamic development
expressed in remnants of Variscan subductions imprinted in bands of crustal
thickening. A significant feature of the presented model is the
velocity-drop interface (VDI) modelled in the lower part of the crust. We
explain this feature by the anisotropic fabric of the lower crust, which is
characterised as vertical transverse isotropy with the low velocity being
the symmetry axis. The VDI is often interrupted around the boundaries of the
crustal units, usually above locally increased velocities in the lowermost
crust. Due to the north-west–south-east shortening of the crust and the late-Variscan
strike-slip movements along the north-east–south-west oriented sutures preserved in
the BM lithosphere, the anisotropic fabric of the lower crust was partly or
fully erased along the boundaries of original microplates. These weakened
zones accompanied by a velocity increase above the Moho (which indicate an
emplacement of mantle rocks into the lower crust) can represent channels
through which portions of subducted and later molten rocks have percolated
upwards providing magma to subsequently form granitoid plutons.</p>
<p>Fault kinematics can provide information on the relationship and assembly of
tectonic units in an orogen. Magnetic fabric studies of faults where
pseudotachylytes form have recently been used to determine direction and
sense of seismic slip in prehistoric earthquakes. Here we apply this
methodology to study magnetic fabrics of pseudotachylytes in field
structures of the Köli Nappe Complex (central Swedish Caledonides), with
the aim to determine fault kinematics and decipher the role of seismic faulting
in the assembly of the Caledonian nappe pile. Because the pseudotachylyte
veins are thin, we focused on small (ca. 0.2 to 0.03 cm<span class="inline-formula"><sup>3</sup></span>) samples for measuring
the anisotropy of magnetic susceptibility. The small sample size challenges
conventional use of magnetic anisotropy and results acquired from such small
specimens demand cautious interpretation. Importantly, we find that magnetic
fabric results show inverse proportionality among specimen size, degree of
magnetic anisotropy and mean magnetic susceptibility, which is most likely
an analytical artifact related to instrument sensitivity and small sample
dimensions. In general, however, it is shown that the principal axes of
magnetic susceptibility correspond to the orientation of foliation and
lineation, where the maximum susceptibility (<span class="inline-formula"><i>k</i><sub>1</sub></span>) is parallel to the
mineral lineation, and the minimum susceptibility (<span class="inline-formula"><i>k</i><sub>3</sub></span>) is dominantly
oriented normal to schistosity. Furthermore, the studied pseudotachylytes
develop distinct magnetic properties. Pristine pseudotachylytes preserve a
signal of ferrimagnetic magnetite that likely formed during faulting. In
contrast, portions of the pseudotachylytes have altered, with a tendency of
magnetite to break down to form chlorite. Despite magnetite breakdown, the
altered pseudotachylyte mean magnetic susceptibility is nearly twice that of
altered pseudotachylyte, likely originating from the Fe-rich chlorite, as
implied by temperature-dependent susceptibility measurements and thin-section observations. Analysis of structural and magnetic fabric data
indicates that seismic faulting occurred during exhumation into the upper
crust, but these data yield no kinematic information on the direction and sense of
seismic slip. Additionally, the combined structural field and magnetic
fabric data suggest that seismic faulting was postdated by brittle E–W
extensional deformation along steep normal faults. Although the objective of
finding kinematic indicators for the faulting was not fully achieved, we
believe that the results from this study may help guide future studies of
magnetic anisotropy with small specimens (<span class="inline-formula"><1</span> cm<span class="inline-formula"><sup>3</sup></span>), as well as
in the interpretation of magnetic properties of pseudotachylytes.</p>
<p>Uranium–lead (U–Pb) geochronology was conducted by laser ablation – inductively coupled
plasma mass spectrometry (LA-ICPMS) on 7175 detrital zircon grains from
29 samples from the Coconino Sandstone, Moenkopi Formation, and
Chinle Formation. These samples were recovered from <span class="inline-formula">∼</span> 520 m of
drill core that was acquired during the Colorado Plateau Coring Project
(CPCP), located in Petrified Forest National Park (Arizona).</p>
<p>A sample from the lower Permian Coconino Sandstone yields a broad
distribution of Proterozoic and Paleozoic ages that are consistent with
derivation from the Appalachian and Ouachita orogens, with little input from
local basement or Ancestral Rocky Mountain sources. Four samples from the
Holbrook Member of the Moenkopi Formation yield a different set of
Precambrian and Paleozoic age groups, indicating derivation from the
Ouachita orogen, the East Mexico arc, and the Permo-Triassic arc built along
the Cordilleran margin.</p>
<p>A total of 23 samples from the Chinle Formation contain variable proportions
of Proterozoic and Paleozoic zircon grains but are dominated by Late
Triassic grains. LA-ICPMS ages of these grains belong to five main groups
that correspond to the Mesa Redondo Member, Blue Mesa Member and lower part
of the Sonsela Member, upper part of the Sonsela Member, middle part of the
Petrified Forest Member, and upper part of the Petrified Forest Member. The
ages of pre-Triassic grains also correspond to these chronostratigraphic
units and are interpreted to reflect varying contributions from the
Appalachian orogen to the east, Ouachita orogen to the southeast,
Precambrian basement exposed in the ancestral Mogollon Highlands to the
south, East Mexico arc, and Permian–Triassic arc built along the southern
Cordilleran margin. Triassic grains in each chronostratigraphic unit also
have distinct U and thorium (Th) concentrations, which are interpreted to reflect
temporal changes in the chemistry of arc magmatism.</p>
<p><span id="page258"/>Comparison of our LA-ICPMS ages with available chemical abrasion thermal ionization mass spectrometry (CA-TIMS) ages and new
magnetostratigraphic data provides new insights into the depositional
history of the Chinle Formation, as well as methods utilized to determine
depositional ages of fluvial strata. For parts of the Chinle Formation that
are dominated by fine-grained clastic strata (e.g., mudstone and siltstone),
such as the Blue Mesa Member and Petrified Forest Member, all three
chronometers agree (to within <span class="inline-formula">∼</span> 1 Myr), and robust
depositional chronologies have been determined. In contrast, for
stratigraphic intervals dominated by coarse-grained clastic strata (e.g.,
sandstone), such as most of the Sonsela Member, the three chronologic
records disagree due to recycling of older zircon grains and variable
dilution of syn-depositional-age grains. This results in LA-ICPMS ages that
significantly predate deposition and CA-TIMS ages that range between the
other two chronometers. These complications challenge attempts to establish
a well-defined chronostratigraphic age model for the Chinle Formation.</p>
<p>This study reports on the glaciochemistry of a deep ice
core (182 m long) drilled in 2009 at Mount Elbrus in the Caucasus, Russia.
Radiocarbon dating of the particulate organic carbon fraction in the ice
suggests that the basal ice dates to <span class="inline-formula">280±400</span> CE (Common Era).
Based on chemical stratigraphy, the upper 168.6 m of the core was dated by
counting annual layers. The seasonally resolved chemical records cover the
years 1774–2009 CE, thus being useful to reconstruct many aspects of
atmospheric pollution in south-eastern Europe from pre-industrial times to
the present day. After having examined the extent to which the arrival of large
dust plumes originating from the Sahara and Middle East modifies the chemical
composition of the Elbrus (ELB) snow and ice layers, we focus on the
dust-free sulfur pollution. The ELB dust-free sulfate levels indicate a 6-
and 7-fold increase from 1774–1900 to 1980–1995 in winter and summer,
respectively. Remaining close to <span class="inline-formula">55±10</span> ppb during the 19th
century, the annual dust-free sulfate levels started to rise at a mean rate
of <span class="inline-formula">∼3</span> ppb per year from 1920 to 1950. The annual increase
accelerated between 1950 and 1975 (8 ppb per year), with levels reaching a
maximum between 1980 and 1990 (<span class="inline-formula">376±10</span> ppb) and subsequently
decreasing to <span class="inline-formula">270±18</span> ppb at the beginning of the 21st
century. Long-term dust-free sulfate trends observed in the ELB ice cores
are compared with those previously obtained in Alpine and Altai (Siberia)
ice, with the most important differences consisting in a much earlier onset and a
more pronounced decrease in the sulfur pollution over the last 3 decades
in western Europe than south-eastern Europe and Siberia.</p>
Geotechnical site investigations are essential in determining subsoil stratigraphy and soil strength and is considered mandatory for design of foundations. This study presents the generalized profiles for subsurface stratigraphy and insitu soil strength (average SPT N values) for different sectors of Islamabad on the basis of wide-ranging experimental work carried out by several agencies in fieldand laboratory testing carried out at the number of locations in the study area. Data from 208 geotechnical site investigations of Islamabad have been collected and subsurface profiling for those sectors is carried out that had more than four data points. The experimental data of the study area has shown potential for development of profile map for 11 different sectors of Islamabad using data of 144 geotechnical site investigations. Generalized soil profile and average SPT N values for each sector have been generated to a depth of 7m which is considered sufficient for lightly loaded structures with shallow foundations. Average SPT N value profile coupled with soil stratigraphy for each zone is established that can used to determine shear strength parameters and bearing capacity of soil using SPT based empirical correlations. The generalized soil profiles will be helpful during feasibility study and planning geotechnical site investigations for mega projects and can also be used to determine engineering properties of subsoil for small scale projects.
Michal Šujan, Alexander Lačný, Régis Braucher
et al.
Assessment of vertical movements of tectonically bounded
blocks is crucial for determination of geohazards in densely
inhabited zones, such as the border zone of western Slovakia
and eastern Austria. The morphostructure of the Malé Karpaty
Mts. divides the Vienna and Danube basins in the Western
Carpathian – Eastern Alpine junction, and its neotectonic
activity is of high importance. This study was focused on
26Al/10Be burial dating of fluvial sediment in the Stará Garda
Cave, located in the central part of the mountains. The structural
research revealed predisposition of forming of horizontal
passages in low angle to subhorizontal bedrock stratification
together with low-grade metamorphic foliation. Fluvial origin
of the passages was inferred from mezoscale erosional features
on the bedrock as well as from facies character of the well preserved
sedimentary profile. Cave sediment was according to
petrographic analysis derived from a watershed comparable
to recent one of the Stupavský Potok Stream. Three analysed
dating samples provided low values of isotopic concentrations,
allowing us only to calculate the minimum burial age of the
deposit of 1.72 Ma. Assuming the low position of the cave
above recent surface streams, resulting maximum incision rate
of 26 m/Ma indicates very low uplift of the mountains horst
during the Quaternary. The slow incision of the river network
is in good agreement with a widespread preservation of the
planation surface called "Mid-mountain level". In contrast are
relatively high values of palaeodenudation rates inferred from
isotopic concentrations. Generally, our results indicate that the
Malé Karpaty Mts. horst underwent relatively intense but short
uplift in the Early Pleistocene, followed by very moderate uplift
up to the recent.
Key words: Western Carpathians, Malé Karpaty Mts., fluvial
cave sediment, burial dating, Early Pleistocene, neotectonics.
Zgodnja pleistocenska starost fluvialnih
sedimentov v jami Stará Garda, ki jo je dala 26Al/10Be datacija:
uporabnost za geomorfni razvoj Nizkih Karpatov (Zahodni
Karpati)
Ocena vertikalnih premikov tektonsko omejenih blokov je
ključna za določitev geohazardov v gosto naseljenih območjih.
Morfostruktura Malih Karpatov deli Dunajski in Donavski bazen
na stičišču Zahodnih Karpatov – Vzhodnih Alp in njegova
neotektonska aktivnost je zelo pomembna. Študija se je posvetila
26Al/10Be dataciji fluvialnih sedimentov v jami Stará Garda
v osrednjem delu gorovja. Strukturna raziskava je razkrila
predispozicijo
oblikovanja vodoravnih jamskih rovov pod nizkim
kotom v odvisnosti od subhorozontalne stratifikacije kamnine
ter tudi z nizko stopnjo metamorfne foliacije. Na fluvialno
poreklo rovov smo sklepali iz srednje velikih erozijskih oblik na
njihovih stenah kot tudi iz lastnosti faciesov dobro ohranjenega
sedimentnega profila. Glede na petrografske analize
jamski
sediment izhaja iz povodja, ki je primerljiv z recentnim povodjem
potoka Stupavský. Trije analizirani vzorci so nam dali
nizke vrednosti koncentracij izotopov, ki so nam omogočile
le izračun najnižje pokopne starosti sedimenta, ki je znašala
1,72 Ma. Če upoštevamo, da leži jama nizko nad recentnimi
vodnimi tokovi, dobimo maksimalno hitrost vrezovanja dolin
samo 26 m/Ma, kar kaže na zelo majhen tektonski dvig v času
kvartarja. Počasno vrezovanje rečne mreže se dobro ujema s
široko ohranjenim uravnanim površjem, imenovanim »Srednjegorska
uravnava«. V nasprotju pa so sorazmerno visoke
vrednosti hitrosti paleodenudacije, ki izhajajo iz koncentracij
izotopov. Na splošno naši rezultati kažejo, da je bil horst Nizkih
Karpatov podvržen relativno močnemu, toda kratkemu dvigovanju
v spodnjem pleistocenu, ki mu je sledil zmeren dvig do
sedanjosti.
Ključne besede: Zahodni Karpati, Nizki Karpati, fluvialni
jamski sedimenti, pokopna datacija, starejši pleistocen, neotektonika.
ALESSANDRO BOSSIO, FRANCESCO GUELFI, ROBERTO MAZZEI
et al.
The geological mapping and the biostratigraphic study of Neogene sediments outcropping near Palmariggi, a small area between Otranto and Maglie (Puglia), have been carried out. Above the dolomitic limestone units of the Cretaceous-Oligocene platform three sedimentary cycles have been recognized, one of Miocene and two of Pliocene age. The first cycle consists of two units: the Pietra leccese and the overlying Calcareniti di Andrano; the second cycle is represented by the Lèuca Formation and the last cycle by the Uggiano la Chiesa Formation. The pre-Neogene units are affected by a folding episode with major structures trending NNW- SSE. A subsequent tectonic event characterized by folds with axial directions interferring with the previous one has been detected in the pre-Neogene units. The latter deformation affects also the Miocene successions. Both the previous deformative episodes control the outcrop distribution of the Neogene sediments, preserved in the low structural sites such as synclinal cores. In the Palmariggi area an extensional tectonics of pre-Pliocene age follows the folding related to the compressive episodes. The normal faults linked to this late extension, show a NNW-SSE trend.
The article describes the Neolithic pottery complex of the Satygino type. It was found in multilayer settlement Nizhnee ozero III located at the base of the East macroslope of Ural Mountain, in south part of the North Transurals. Three groups of pottery were recorded in remains of constructions № 1–3 dated to the Neolithic. Two of them have a great similarity with findings of the Koshkino and the Sumpan`ya types. The paper deals with the third group of ceramic. Most of these potteries are the closed-shape vessels, some of them profiled and rims do not have influxes. The bottoms are plain but there are also rounded. Sculptural ornamentation as relief bands, located in the upper part of the body, expresses the main feature of this ceramic group. They are straight or wavy, formed with applying technique or stretching of the vessel walls, decorated with incisions. All other patterns made in the technique of drawing and pricking, rarer of pricking-dragging. The analysis of the typological, morphological and technological characteristics, the planigraphy and stratigraphy of finds location, radiocarbon dates and comparisons with the Neolithic complexes of the Transurals, West Siberia and neighbor territories allowed to make hypotheses about cultural identity and period of existence of this specific complex. This pottery considered in the context of the Neolithic cultures of East Europe, conditionally called the pricking-ornamented cultures. It has analogy with the Koshkino, Boborykino and Satygino types of ceramic in the Transurals and West Siberia. In our opinion this pottery has the greatest similarity to the pottery of the Satygino type from the settlements of Sumpan`ya IV, VI of Ust`Vagil`skiy hill. In our view, the proposal to include the Satygino type in the area of the Boborykino culture is not justified. At present stratigraphic observations, the results of radiocarbon dating and the differences in technology and ornamentation of the ware shows the presence of at least two groups of relief bands ceramics on the territory of the Transurals and West Siberia, with local and/or chronological differences. The Satygino type pottery existed in parallel with the Sumpan`ya culture and at some point with the Koshkino culture on the territory of the North Transurals and the Konda lowland probably about 6750–5000 years BC (cal.). The Boborykino type of ceramic (including relief bands) had a larger area of extension and existed later, about 4700–3800 years BC (cal.), apparently together with the Bas`yanovo type of ceramic.
The development of microfocused X-ray computed tomography (CT) devices
enables digital imaging analysis at the pore scale. The applications of
these devices are diverse in soil mechanics, geotechnical and
geoenvironmental engineering, petroleum engineering, and agricultural
engineering. In particular, the imaging of the pore space in porous media
has contributed to numerical simulations for single-phase and multiphase
flows or contaminant transport through the pore structure as
three-dimensional image data. These obtained results are affected by the
pore diameter; therefore, it is necessary to verify the image preprocessing
for the image analysis and to validate the pore diameters obtained from the
CT image data. Moreover, it is meaningful to produce the physical parameters
in a representative element volume (REV) and significant to define the
dimension of the REV. This paper describes the underlying method of image
processing and analysis and discusses the physical properties of Toyoura
sand for the verification of the image analysis based on the definition of
the REV. On the basis of the obtained verification results, a pore-diameter
analysis can be conducted and validated by a comparison with the
experimental work and image analysis. The pore diameter is deduced from
Young–Laplace's law and a water retention test for the drainage process.
The results from previous study and perforated-pore diameter originally
proposed in this study, called the voxel-percolation method (VPM), are
compared in this paper. In addition, the limitations of the REV, the
definition of the pore diameter, and the effectiveness of the VPM for an
assessment of the pore diameter are discussed.