Hasil untuk "Stratigraphy"

A. J. Cawood, D. A. Ferrill, K. J. Smart et al.

<p>Understanding the distribution and geometry of subsurface faults is critical for predicting fault penetration and associated leakage of fluids such as groundwater, hydrocarbons, and injected anthropogenic waste through sealing intervals. Fault dimensions are often underestimated due to the resolution limits of seismic reflection data, which only image portions of faults with sufficient displacement to offset seismic reflectors. To address this fault underestimation problem, we quantify relationships between host rock composition and fault displacement gradients using a well-exposed outcrop of normal faults in mechanically layered sedimentary rocks in the footwall to the west branch of the Moab Fault, Utah. We integrate high-resolution digital photogrammetry, structural mapping, X-ray diffraction (XRD) mineralogy, and Schmidt rebound measurements to analyze how mineralogy and mechanical properties influence fault displacement vs. height relationships. Our results indicate that normal fault displacement gradients tend to be higher in less competent beds and lower in more competent strata, and that fault displacement gradient is positively correlated with clay content and negatively correlated with strong minerals (e.g., quartz, feldspar, dolomite). Outcrop-derived relationships are used to build a predictive framework that uses fault displacement and mineralogy to predict fault height. We apply this framework to a worked seismic interpretation example and demonstrate that fault dimensions are likely substantially underestimated in conservative seismic interpretations. Our results highlight the importance of mechanical stratigraphy in controlling fault geometry and provide a data-driven approach for estimating sub-seismic fault dimensions, with implications for reservoir characterization, fluid containment, and geohazard assessment.</p>

Philipp Stojakowits, Manfred Rösch, Herbert Röhm

95 m core from Moormerland, Leer District (Lower Saxony / Germany), was investigated by pollen analysis. The pollen record is focused on organic layers at 90–88 m, around 70 m, and 57–45 m. The pollen assemblage is a mixture of Pliocene and Pleistocene pollen types, with Pinus dominating, but Taxodium -type, Nyssa , Liquidambar , Eucommia , Carya , Sciadopitys , Tsuga and others also participating as Pliocene elements, as well as Quercus , Ulmus , Taxus , and others as Pleistocene elements. Wetlands and swamp forests under a warm climate are represented.

Giuseppe Angileri, Graziella Bernardo, Giuseppina Currò et al.

The existing built heritage is excessively energy intensive compared to the standards required by European policies that promote zero- or near-zero-energy buildings. Hence the need to promote a radical energy requalification of the existing stock through ad hoc solutions. In the modelling of buildings undergoing redevelopment, the boundary conditions considered by the designer are often underestimated, resulting in a digital model that does not perfectly adhere to reality, due to a lack of historical and documentary knowledge. The present work—which concerns the Santa Maria Micaela residential complex built in Valencia by architect Santiago Artal Ríos, a representative work of Spanish Modernism—aims to overcome this vulnus with modelling that also takes into account historical and archive information. The housing complex was studied using a multidisciplinary approach with historical–archival analyses and site surveys that allowed BIM modelling and localisation in a WEB-GIS platform. The modelling took into account the peculiarities of the original design (exposure, windiness, and shading) and data from historical research (stratigraphy of building elements, dimensions, types of materials). The energy simulation, on the other hand, referred to a representative dwelling unit of the complex, and using SolidWorks software the ventilation flows were evaluated, which made it possible to create a model that was more in keeping with reality and to more correctly identify the performance upgrading proposal. The energy improvement was then evaluated according to the hypothesised interventions using two different analysis methodologies, TerMus and CE3X, for direct comparison. The transposition into WebGIS then made it possible to assess the potential of a digital platform to enhance information sharing.

Magdalena Kolenc, Aneta Piplica, Martina Čelhar et al.

The significance of birds in the medieval human diet has been greatly explored in Europe. However, there is a lack of systematic analysis of data from Croatia. Avian remains dated to the Late Medieval and Early Modern Periods from five archaeological sites in continental Croatia underwent skeletal and taxonomic analysis. Age groups were determined and sex identification was conducted using visual and X-ray diagnostics. Chicken bone measurements were taken, and the logarithmic size index (LSI) technique was performed. Statistical analysis was applied to explore differences between sites. A total of 694 avian remains were studied, revealing 10 species/genera. Avian remains ranged from 8.88% to 20.32% across sites, with the highest percentage found at the urban site BAN. Hens outnumbered cockerels across all sites, with adult chickens prevailing over immature and subadult ones. Chicken sizes were generally consistent across sites, except for castle MIL, where a larger breed was identified. Cockerels tended to be larger than hens, except for one small-sized spurred specimen. To conclude, bird exploitation complemented the use of other animals in diets. Chickens were vital for eggs and meat, with monasteries excelling in bird husbandry over castles. Inhabitants of urban areas mainly consumed bird meat. Castles showed high status through game and imported birds. The aim of this article was to fill in the gap of information regarding the exploitation and consumption of birds at Croatian sites during the Late Medieval and Early Modern Periods.

A. S. Potapova, V. A. Kuznetsova

The purpose of this work is to improve the predictive ability of the geological model of coastal formations when assessing hydrocarbon reserves and laying production wells. The article presents the results of work on the analysis of the geometry of sand bodies of the formations of the TP group of the Tanopchinskaya suite. To determine the morphology of sandstones, the authors used an integrated approach that takes into account: the results of sedimentological core studies, well logging data, 3D seismic materials. The authors studied in detail the conditions for the formation of these rocks on the basis of actual material (core), and presented photographs with characteristic structural and textural features of the rocks, which make it possible to establish the conditions for their formation. Spectral decomposition sections were analyzed in detail in the studied interval at several license areas of NOVATEK.The reasons for changes in the geometry of sand bodies from the perspective of sequence stratigraphy have been established and explained. In addition, an idea has been formed about the vertical evolution of the coastal zone under conditions of sea transgression. The filtration and reservoir properties of rocks were also analyzed based on measurements of porosity and permeability on more than 700 core samples formed in different sedimentation environments. Recommendations are given for the practical use of established patterns of changes in reservoir properties and the geometry of sand bodies when constructing a geological model of hydrocarbon deposits, which will certainly improve the efficiency of production drilling.

Üftade Muşkara, Ayşin Konak

Kendale Hecala is located on the Ambar River in the Upper Tigris Basin, province of Diyarbakır in Southeast Anatolia. Various raw materials, including obsidian, radiolarite, chert, jasper, chalcedony, and quartzite, were used in the lithic industry. Obsidian artefacts constitute an average of 64% of the chipped stone assemblage. Technological analysis reveals that obsidian was brought to the settlement as nodules and chipped into various tools at the settlement. Understanding the operational sequence of the lithic industry, chaîne opératoire, including the distribution of raw material from source to site, is important to demonstrate the socio-cultural organization of the settlement in Southeastern Anatolia during the Ubaid period. In order to identify source varieties, the obsidian artefacts uncovered from Ubaid layers of Kendale Hecala were analyzed by macro-observations, and the characterization of archaeological samples was performed using a handheld XRF. Multivariate analysis of the data indicates the use of obsidian from different resources at the settlement, including Nemrut Dağ, Bingöl B, and Group 3d.

A. Tibaldi, A. Tibaldi, N. Corti et al.

<p>We collected drone data to quantify the kinematics at extensional fractures and normal faults, integrated this information with seismological data to reconstruct the stress field, and critically compared the results with previous fieldwork to assess the best practice. As a key site, we analyzed a sector of the northeast rift of Mt Etna, an area affected by continuous ground deformation linked to gravity sliding of the volcano's eastern flank and dike injections. The studied sector is characterized also by the existence of eruptive craters and fissures and lava flows. This work shows that this rift segment is affected by a series of NNE- to NE-striking, parallel extensional fractures characterized by an opening mode along an average N105.7<span class="inline-formula">^∘</span> vector. The stress field is characterized by a <span class="inline-formula"><i>σ</i>_Hmin</span> trending northwest–southeast. Normal faults strike parallel to the extensional fractures. The extensional strain obtained by cumulating the net offset at extensional fractures with the fault heave gives a stretching ratio of 1.003 in the northeastern part of the study area and 1.005 in the southwestern part. Given a maximum age of 1614 CE for the offset lavas, we obtained an extension rate of 1.9 cm yr<span class="inline-formula">⁻¹</span> for the last 406 years. This value is consistent with the slip along the Pernicana Fault system, confirming that the NE rift structures accommodate the sliding of the eastern flank of the volcano.</p>

Javad Biglari, Aabbas Kangi , Abdol Reza Jafarian

Introduction Two fundamental goals are followed in this paper: 1- Active neotectonics of the Kopeh Dagh Mountains particularly in its central part that is called the Bakharden-Quchan Zone in NE Iran for special features of faulting and role of faults within this zone in the collision between Arabia-Eurasia plates. 2- Seismicity hazards of faulting to recognize the relationship between asperities and earthquakes through analyzing the correlation of fractal dimension and b-value parameters. The Kopeh Dagh Mountain is accommodating a large portion of northward motion of central Iran with respect to Eurasia, involving a major right- lateral strike-slip fault system in its central part (the Bakharden-Quchan Zone). This fault system corresponds to the northeastern boundary of the Arabia-Eurasia collision and can be considered to be a lithospheric scale tectonic feature. The Kopeh Dagh Mountain forms a linear intercontinental fold-thrust belt trending NW-SE between the stable Turan platform and central Iran (Afshar Harb, 1979; Hollingsworth et al., 2006; Shabanian et al., 2009; Shahidi et al., 2013). Materials and methods This research uses both historical and instrumental seismicity data along with observations from Landsat 7 satellite imageries, topographic data (SRTM), field observations and mathematical fractal dimension (D) model plus integral mathematical functions to find a logical correlation between tectonic movements, asperities and earthquakes in different active zones. Results There is an array of active right-lateral strike-slip faults in the central part of the Kopeh Dagh Mountain which obliquely cut the range and produce offsets of several Kilometers in the geological structures. These faults all end in thrusting and link to blind faults, revealed by the uplifts and incision of the Late Quaternary terraces. These faults have rotated around their vertical axes and can account for several Kilometers of the N-S shortening. They are responsible for major destructive earthquakes in both 19th and 20th centuries and represent important seismic hazards for populous regions of NE Iran. These faults also require several Kilometers along-strike extension that is taken up by the westward component of motion between south Caspian sea basin, Shahrood fault system and both Eurasia and central Iran (Hollingsworth et al., 2006; Shabanian et al., 2009; Bretis et al., 2012). Discussion The Bakharden-Quchan faults have identifiable ends, where they turn into thrusting and link to blind faults. The fault changing mechanism to reverse has caused increase of stress, shortening by thrusting in their end bending. Structural relation faults between this zone and the Binaloud Mountain through Meshkan transfer zone which is the major motion engine of this zone to put it constantly under neotectonic stresses for convergence of Arabia-Eurasia plates since the last Alpine orogeny phase. Most of the seismic activities of this zone could provide us with precious data on crust tension distribution through microseismic and computing parameters of b-value, fractal dimension (D) and mapping of local stresses. In neotectonic active zone b Acknowledgment We thank the Department of Geology of Shahrood Azad Islamic University and acknowledge support of the respectable editor and reviewers of the Journal of Economic Geology and thank them for their constructive suggestions on alterations to the manuscript. References Afshar Harb, A., 1979. The stratigraphy, tectonics and petroleum geology of the Kopeh Dagh region, Northern Iran. Ph.D. thesis, Royal school of Mines, London, England, 17 pp. Aki, K., 1981. Source and scatering effects on the spectra of small local earthquakes. Bulletin of the Seismological Society of America, 71(6): 1687–1700. Bretis, B., Grasemann, B. and Conradi, F., 2012. An Active Fault Zone in the Western Kopeh Dagh (Iran). Austrian Journal of Earth Sciences, 105(3): 480–192. Hollingsworth, J., Jackson, J., Walker, R., Gheitanchi, M.‌R. and Bolourchi, M.‌J., 2006. Strike-slip faulting, rotation, and along-strike elongation in the Kopeh Dagh mountains, NE Iran. Geophysical Journal International, 166(3): 1161–1177. King, G., 1983. The accommodation of large strains in the upper lithosphere of the earth and other solids by self-similar fault systems: the geometrical origin of b-value. Pure and Applied Geophysics, 121(5–6): 761–815. Shabanian, E., Siame, L., Bellier, O., Benedetti, L. and Abbassi, M.‌R. 2009. Quaternary slip rates along the northeastern boundary of the Arabia-Eurasia collision zone (Kopeh Dagh Mountains, Northeast Iran): Geophysical Journal International, 178(2): 1055–1077. Shahidi, A., Nazari, H. and Ghaemi, F., 2013. Structure of Iran-Kopeh Dagh. Mining and Geology Organization of Iran, Tehran, 197 pp. Wiemer, S. and Wyss, M., 2002. Mapping spatial variability of the frequency-magnitude distribution of earthquakes. Advances in Geophysics, 45: 259–302.

Gemma Aiello, Mauro Caccavale

This study discusses the siliciclastic to bioclastic deposits (in particular, the rhodolith deposits) in the Gulf of Naples based on sedimentological and seismo-stratigraphic data. The selected areas are offshore Ischia Island (offshore Casamicciola, Ischia Channel), where a dense network of sea-bottom samples has been collected, coupled with Sparker Multi-tip seismic lines, and offshore Procida–Pozzuoli (Procida Channel), where sea-bottom samples are available, in addition to Sparker seismic profiles. The basic methods applied in this research include sedimentological analysis, processing sedimentological data, and assessing seismo-stratigraphic criteria and techniques. In the Gulf of Naples, and particularly offshore Ischia, bioclastic sedimentation has been controlled by seafloor topography coupled with the oceanographic setting. Wide seismo-stratigraphic units include the bioclastic deposits in their uppermost part. Offshore Procida–Pozzuoli, siliciclastic deposits appear to prevail, coupled with pyroclastic units, and no significant bioclastic or rhodolith deposits have been outlined based on sedimentological and seismo-stratigraphic data. The occurrence of mixed siliciclastic–carbonate depositional systems is highlighted in this section of the Gulf of Naples based on the obtained results, which can be compared with similar systems recognized in the central Tyrrhenian Sea (Pontine Islands).

Mercedes Ferrer, Luis González de Vallejo, José Madeira et al.

Evidence for frequent, large landslides on the flanks of the volcanic edifices forming the Canary Islands include outstanding landslide scars and their correlative submarine and subaerial rock and debris avalanche deposits. These landslides involved volumes ranging from tens to hundreds of km³. The sudden entry of large volumes of rock masses in the sea may have triggered tsunamis capable of affecting the source and neighboring islands, with the resulting huge waves dragging coastal and seabed materials and fauna and redepositing them inland. Here, we present new geological evidence and geochronological data of at least five megatsunamis in Tenerife, Lanzarote, and Gran Canaria, triggered by island flank megalandslides, and occasionally explosive eruptions, during the last 1 million years. The exceptional preservation of the megatsunami deposits and the large area they cover, particularly in Tenerife, provide fundamental data on the number of tsunami events and run-ups, and allow proposals on the sources and age of the tsunamis. Tsunami run-up heights up to 290 m above coeval sea level, some of the highest known on Earth in recent geological times, were estimated based on sedimentological, geomorphological, paleontological, and geochronological data. The research results made it possible to estimate the recurrence of tsunamis in the archipelago during the last hundreds of thousands of years, and to establish relationships between tsunami deposits and the probable triggering island flank landslides.

A. Causer, L. Pérez-Díaz, L. Pérez-Díaz et al.

<p>Plate tectonic modellers often rely on the identification of “break-up” markers to reconstruct the early stages of continental separation. Along the Iberian-Newfoundland margin, so-called break-up markers include interpretations of old magnetic anomalies from the M series, as well as the “J anomaly”. These have been used as the basis for plate tectonic reconstructions are based on the concept that these anomalies pinpoint the location of first oceanic lithosphere. However, uncertainties in the location and interpretation of break-up markers, as well as the difficulty in dating them precisely, has led to plate models that differ in both the timing and relative palaeo-positions of Iberia and Newfoundland during separation.</p> <p>We use newly available seismic data from the Southern Newfoundland Basin (SNB) to assess the suitability of commonly used break-up markers along the Newfoundland margin for plate kinematic reconstructions. Our data show that basement associated with the younger M-series magnetic anomalies is comprised of exhumed mantle and magmatic additions and most likely represents transitional domains and not true oceanic lithosphere. Because rifting propagated northward, we argue that M-series anomaly identifications further north, although in a region not imaged by our seismic, are also unlikely to be diagnostic of true oceanic crust beneath the SNB. Similarly, our data also allow us to show that the high amplitude of the J Anomaly is associated with a zone of exhumed mantle punctuated by significant volcanic additions and at times characterized by interbedded volcanics and sediments. Magmatic activity in the SNB at a time coinciding with M4 (128&thinsp;Ma) and the presence of SDR packages onlapping onto a basement fault suggest that, at this time, plate divergence was still being accommodated by tectonic faulting.</p> <p>We illustrate the differences in the relative positions of Iberia and Newfoundland across published plate reconstructions and discuss how these are a direct consequence of the uncertainties introduced into the modelling procedure by the use of extended continental margin data (dubious magnetic anomaly identifications, break-up unconformity interpretations). We conclude that a different approach is needed for constraining plate kinematics of the Iberian plate pre-M0 times.</p>

Spencer G. Lucas

The use of boundary stratotypes to define chronostratigraphic units began in the 1960s, and, in the 1980s, these were called Global Stratotype Sections and Points (GSSPs). Approximately two-thirds of the GSSPs of the bases of the Phanerozoic stage (71 of 102 in September 2018) have been ratified by the International Commission on Stratigraphy. However, this apparent progress toward precise definition of a Phanerozoic chronostratigraphic timescale is underlain by multiple problems of philosophy and methodology that include: (1) inconsistency in how chronostratigraphic units are being named and defined; (2) arbitrary decisions as to GSSP level, many based on arbitrarily chosen points in hypothetical chronomorphoclines of microfossils; (3) hierarchical reductionism, which makes the stage base the same as the base of the series, system, erathem and eonothem, thereby trivializing the significance of the boundaries of these larger chronostratigraphic units; (4) stability achieved by the non-scientific process of designating a GSSP once ratified as immutable; (5) the unworkable concept of a standard set of global stages; (6) the fallacy that a GSSP location can somehow define a recognizable (correlateable) global time line; (7) imprecision in GSSP correlation because the primary signals are largely single taxon biotic events that are inherently diachronous due to the limitations of fossil distributions by sampling, facies and provincialism; and (8) the politics of the International Commission on Stratigraphy and the small groups of specialists who select and vote on GSSPs. Chronostratigraphy needs to return to the concepts of natural chronostratigraphy, with improvements based on modern techniques like quantitative biostratigraphy. We need to standardize the chronostratigraphic scale, and the International Commission on Stratigraphy needs to rethink the philosophy and practices by which this is being done, so that we can move forward to produce the most informative chronostratigraphy possible based on a consistent methodology that allows the updating and obtaining of high accuracy and precision as new data become available.

Mariya A. Balabanova, Ivan I. Marchenko, Natalya Yu. Limberis

The article is devoted to the burial complex and the skull of the Novotitorovka culture from burial no. 35 of the Ovalny burial mound, Kalininsky district of the Krasnodar region. The burial itself was non-inventory, but it was synchronous with burial no. 26. Both burials were excavated from the level of the ancient surface and covered by the same barrow. The bones from the studied burial belonged to a young man, who died at the age of 20-25. His craniological type is characterized by meso-dolichocrania, ellipsoidal vertical norm, the average width of forehead, wide and low face, orthognathy-like in a vertical plane and slightly profiled at the level of low eye sockets. The face is also characterized by narrow and sharply protruding nasal bones. The article also deals with the possible relationship between the tribes of the Novotitorovka culture and the Azov-Black Sea sites of Catacomb culture. This conclusion is based on the results of intergroup comparison by the method of canonical analysis. The studied skull of the Novotitorovka culture has a morphological complex that characterizes the groups of burials of the Catacomb culture localized on the terraces of the Ingul river and on the terraces of the Don river left bank. This conclusion calls into question the archaeologists’ hypothesis on the connection of the the Novotitorovka culture with the tribes of the Novosvobodnenskaya culture and the Maykop culture.

Pedro Robledo Ardila, Luis Pomar

V obalnih stenah na Mallorci (Zahodno Sredozemlje) so obsežni izdanki zgornjemiocenskih karbonatnih kamnin. Na vzhodni obali otoka prekrivajo grebenski sklop mesinijski plitvovodni karbonati. Tod so v zgornjemiocenskih kamninah številne paleokraške podorne strukture. V apnence Santanyí so vrezane strukture v obliki črke V, kar kaže na udiranje stropov jam, nastalih v spodaj ležečih grebenskih sklopih. Glede na model je mogoče nastanek nekaterih izmed teh kraških podornih struktur povezati z zgodnjimi diagenetskimi procesi, na katere so vplivale pogoste spremembe nivoja morske gladine. V času nizkega nivoja morske gladine je sladkovodni tok izdolbel jamski sistem v bližini vodne gladine na tak način, da je raztapljal aragonit v frontalnem faciesu in skupke koral v obstoječih lagunskih plasteh. Ta jamski sistem se je razvijal v bližini površinske erozijske baze. Med kasnejšim dvigom morske gladine so plasti notranjega dela šelfa prekrile predhodno zakraselo jedro grebena in izvenlagunske plasti. Vrezane »V« strukture je lahko povzročila povečana teža odloženih plitvovodnih karbonatov, zaradi česar je prihajalo do gravitacijskih udiranj jamskih stropov v času, ko te plasti še niso bile popolnoma strjene. In the sea cliffs on the Mallorca Island, Western Mediterranean there are extensive outcrops of Upper Miocene carbonate rocks. On the Eastern coast of Mallorca, the reefal complex is overlain by a Messinian shallowwater carbonate complex. There are abundant Paleokarst collapse structures. The Santanyí Limestone beds are affected by V-incasion structures produced by roof collapse of caverns developed in the underlying reefal complex. According to the model, the origin of some of these karst-collapse structures may be related to early diagenetic processes controlled by high-frequency sea-level fluctuations. During lowstands of sea level, freshwater flow might have create a cave system near the water table by dissolution of aragonite in the reef front facies and coral patches existing in the lagoonal beds. This cave system developed near the subaerial erosion surface. During subsequent rise of sea level inner-shelf beds overlaid the previously karstified reef-core and outer-lagoonal beds. Increase of loading by subsequent accretion of the shallow-water carbonates might have produced V-incasion structures by gravitational collapse of cave roofs when these beds were still not completely consolidated.

L. Spruzeniece, S. Piazolo

This study focuses on physiochemical processes occurring in a brittle–ductile shear zone at both fluid-present and fluid-limited conditions. In the studied shear zone (Wyangala, SE Australia), a coarse-grained two-feldspar–quartz–biotite granite is transformed into a medium-grained orthogneiss at the shear zone margins and a fine-grained quartz–muscovite phyllonite in the central parts. <br><br> The orthogneiss displays cataclasis of feldspar and crystal-plastic deformation of quartz. Quartz accommodates most of the deformation and is extensively recrystallized, showing distinct crystallographic preferred orientation (CPO). Feldspar-to-muscovite, biotite-to-muscovite and albitization reactions occur locally at porphyroclasts' fracture surfaces and margins. However, the bulk rock composition shows very little change in respect to the wall rock composition. In contrast, in the shear zone centre quartz occurs as large, weakly deformed porphyroclasts in sizes similar to that in the wall rock, suggesting that it has undergone little deformation. Feldspars and biotite are almost completely reacted to muscovite, which is arranged in a fine-grained interconnected matrix. Muscovite-rich layers contain significant amounts of fine-grained intermixed quartz with random CPO. These domains are interpreted to have accommodated most of the strain. Bulk rock chemistry data show a significant increase in SiO₂ and depletion in NaO content compared to the wall rock composition. <br><br> We suggest that the high- and low-strain microstructures in the shear zone represent markedly different scenarios and cannot be interpreted as a simple sequential development with respect to strain. Instead, we propose that the microstructural and mineralogical changes in the shear zone centre arise from a local metasomatic alteration around a brittle precursor. When the weaker fine-grained microstructure is established, the further flow is controlled by transient porosity created at (i) grain boundaries in fine-grained areas deforming by grain boundary sliding (GBS) and (ii) transient dilatancy sites at porphyroclast–matrix boundaries. Here a growth of secondary quartz occurs from incoming fluid, resulting in significant changes in bulk composition and eventually rheological hardening due to the precipitation-related increase in the mode and grain size of quartz. In contrast, within the shear zone margins the amount of fluid influx and associated reactions is limited; here deformation mainly proceeds by dynamic recrystallization of the igneous quartz grains. <br><br> The studied shear zone exemplifies the role of syn-deformational fluids and fluid-induced reactions on the dominance of deformation processes and subsequent contrasting rheological behaviour at micron to metre scale.

Doan Dinh Lam, Nguyen Khac Su

Benyamin Sapiie, Meli Hadiana

<p class="Normal11ptjustified"><span><a href="http://dx.doi.org/10.17014/ijog.v1i3.189">DOI:10.17014/ijog.v1i3.189</a></span></p><p class="Normal11ptjustified">Sandbox experiment is one of the types of analogue modeling in geological sciences in which the main purpose is simulating deformation style and structural evolution of the sedimentary basin.  Sandbox modeling is one of the effective ways in conducting physically modeling and evaluates complex deformation of sedimentary rocks. The main purpose of this paper is to evaluate structural geometry and deformation history of oblique convergent deformation using of integrated technique of analogue sandbox modeling applying to deformation of Seram Fold-Thrust-Belt (SFTB) in the Seram Island, Eastern Indonesia. Oblique convergent strike-slip deformation has notoriously generated area with structural complex geometry and pattern resulted from role of various local parameters that control stress distributions. Therefore, a special technique is needed for understanding and solving such problem in particular to relate 3D fault geometry and its evolution. The result of four case (Case 1 to 4) modeling setting indicated that two of modeling variables clearly affected in our sandbox modeling results; these are lithological variation (mainly stratigraphy of Seram Island) and pre-existing basement fault geometry (basement configuration). Lithological variation was mainly affected in the total number of faults development.  On the other hand, pre-existing basement fault geometry was highly influenced in the end results particularly fault style and pattern as demonstrated in Case 4 modeling.  In addition, this study concluded that deformation in the Seram Island is clearly best described using oblique convergent strike-slip (transpression) stress system.</p>

Olga L. Kossovaya, Denis I. Leontiev, Tatyana N. Isakova