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Sequence stratigraphy is a branch of geology that studies sedimentary deposits in relation to changes in sea level and sediment supply. It focuses on the identification and interpretation of stratigraphic sequences, which are layers of sedimentary rock that reflect the depositional history and environmental conditions over geological time.

Upwelling of cool seawater, paleoceanographic circulation, paleoclimate, local tectonics and relative sea-level change controlled the lithofacies and sequence stratigraphy of a carbonate ramp and overlying platform that are part of a...more

Upwelling of cool seawater, paleoceanographic circulation, paleoclimate, local tectonics and relative sea-level change controlled the lithofacies and sequence stratigraphy of a carbonate ramp and overlying platform that are part of a temporally well constrained carbonate complex in the Melilla basin, northeastern Morocco. At Melilla, from oldest to youngest, a thirdorder depositional sequence within the carbonate complex contains (1) a retrogradational, transgressive, warm temperate-type rhodalgal ramp; (2) an early highstand, progradational, bioclastic platform composed mainly of a temperate-type, bivalve-rich molechfor facies; and (3) late highstand, progradational to downstepping, subtropical/tropical-type chlorozoan fringing Porites reefs. The change from rhodalgal ramp to molechfor platform occurred at 7:0F0:14 Ma near the Tortonian/Messinian boundary. During a late stage in the development of the bioclastic platform a transition from temperate-type molechfor facies to subtropical/tropical-type chlorozoan facies occurred and is bracketed by chron 3An.2n ( 6.3 -6.6 Ma). Comparison to a well-dated carbonate complex in southeastern Spain at Cabo de Gata suggests that upwelling of cool seawater influenced production of temperate-type limestone within the ramp and platform at Melilla during postulated late Tortonian -early Messinian subtropical/tropical paleoclimatic conditions in the western Paleo-Mediterranean region. The upwelling of cool seawater across the bioclastic platform at Melilla could be related to the beginning of 'siphoning' of deep, cold Atlantic waters into the Paleo-Mediterranean Sea at 7.17 Ma. The facies change within the bioclastic platform from molechfor to chlorozoan facies may be coincident with a reduction of the siphoning of Atlantic waters and the end of upwelling at Melilla during chron 3An.2n. The ramp contains one retrogradational parasequence and the bioclastic platform three progradational parasequences. Minor erosional surfaces that bound the upper surface of the ramp and upper surface of the oldest platform parasequence are related to relative falls in sea level induced by local volcanism and associated tectonic uplift. These local relative falls had little influence on a broader-scale rise to stillstand in relative sea level that controlled development of the transgressive and early highstand systems tracts represented in the ramp and platform, respectively.

Thirty (30) outcrop samples from a section at Gamawa area, Gongola basin, Northern Benue trough were palynologically analyzed to determine age, and paleo-depositional conditions of the strata. Lithological the section is composed of...more

Thirty (30) outcrop samples from a section at Gamawa area, Gongola basin, Northern Benue trough were palynologically analyzed to determine age, and paleo-depositional conditions of the strata. Lithological the section is composed of silts, clays and sandstone intercalations at the base followed by coaly shales and bioturbated silty to fine-grained sandstones at the top. Samples were treated with Hydrochloric and Hydrofluoric acids to remove carbonates and silicates respectively and slides were prepared using standard techniques. A total of 1250 palynomorph specimens were recovered. A palynological age of Upper Maastrichtian was assigned to this interval best on the assemblage of Maastrichtian diagnostic marker species of Longapertites marginatus, Proxaperties operculatus, Spinizonocolpites Baculatus, Monocolpites marginatus especially by the abundance of Pollen Spinizonocolpites Baculatus. Based on the low palynomorph marine index and dominating presence of Palme group species, especially the Spinizonocolpites Species the study suggested a paleodepositional condition of a mangrove forest with evidence of tidal dominated estuarine conditions in mostly brackish water and a temperate climate.

Palombo M.R. & Milli S., Mammal fossil record, depositional setting, and sequence stratigraphy in the Middle-Upper Pleistocene of Roman Basin. (IT ISSN 0394-3356, 2010) In the Roman Basin, and particularly in the Ponte Galeria area,...more

Palombo M.R. & Milli S., Mammal fossil record, depositional setting, and sequence stratigraphy in the Middle-Upper Pleistocene of Roman Basin. (IT ISSN 0394-3356, 2010) In the Roman Basin, and particularly in the Ponte Galeria area, Quaternary vertebrate remains are preserved both in continental and marine sedimentary successions. The facies and sequence stratigraphical analyses carried out in the last twenty years on such deposits led to a detailed local chronostratigraphical framework which fixes some physical and temporal limits to the fist/last local appearances of some mammalian taxa. This contributes to a better definition of faunal complexe, characterizing the biochronological setting proposed for the Quaternary large mammal faunas of the Italian peninsula. Riassunto: Palombo M.R. & Milli S., Record fossile a mammiferi, assetto deposizionale e stratigrafia sequenziale della successione del Pleistocene medio-superiore del Bacino Romano. (IT ISSN 0394-3356, 2010) Nel Bacino Rom...

The practical experience of long-term operation of hydrocarbon deposits con- firms the presence of geomechanical processes and their significant impact on the state of the gas-saturated massif of rocks. In fields that are being operated...more

The practical experience of long-term operation of hydrocarbon deposits con- firms the presence of geomechanical processes and their significant impact on the state of the gas-saturated massif of rocks. In fields that are being operated for a long time, the prospects for industrial hydrocarbon accumulation can be associated with secondary gas traps of non-traditional type, in particular, technogenic ones, which are formed in low-pore collectors. The authors carried out a detailed analysis of the well-known gas and gas condensate fields of Ukraine. The Rudkivske gas field of the Western oil-and-gas bearing region was chosen. The purpose of the study is to clarify the geological conditions for the formation of technogenic collectors and attracting additional volumes of gas under the action of a geomechanical factor while operating the Rudkivske gas field. The quoted results of the research prove the effect of gas extraction from the deposits of the J-h horizon on the formation of seco...

Understanding of complex sedimentary records formed by transgressive systems is critical for hydrocarbon exploration and exploitation, and carbon capture and storage. This paper discusses the facies proportions and preservation of the...more

Understanding of complex sedimentary records formed by transgressive systems is critical for hydrocarbon exploration and exploitation, and carbon capture and storage. This paper discusses the facies proportions and preservation of the Last Interglacial and Holocene transgressive systems tracts in the Netherlands and their applicability as a North Sea Basin analogue for the Early Jurassic Åre Formation in the Norwegian offshore. New and existing data from both (sub-)modern transgressive Rhine records were thoroughly reviewed from a sequence stratigraphic perspective, before volumetrics were calculated and longitudinal trends quantified at reservoir scale. Large differences between the Last Interglacial and Holocene transgressive systems were found: the volume of fluvial deposits is almost six times larger and the volume of organics nearly twenty times larger in the Holocene record than in the Last Interglacial record. In contrast, the volume of estuarine deposits in the Holocene record is only half of that of the Last Interglacial record. Remarkably, both records show similar averaged sediment-trapping rates of 8-9 km 3 /ka. Initial valley configuration and relative sea-level rise-rates during both transgressions were key controls on the volume and spatial arrangement of the transgressive deposits. Relative sea-level fall and river avulsion determined what amount of sediment was left preserved after completion of one interglacial-glacial cycle. Comparison of the Late Quaternary Rhine records with the Late Triassic to Early Jurassic Åre Formation in the Heidrun Field off mid-Norway, showed the potential of the (sub-)modern Rhine records as analogues for ancient stratigraphic records. Especially the transgressive Rhine sequence from the Last Interglacial provided remarkable similarities in facies proportions, preservability, autogenic processes and controlling forcings, ranging from metre-scale vertical-successions to kilometre-scale field-wide events for parts of the Åre Formation. The side-by-side availability of the truncated Last Interglacial and (still) fully preserved Holocene transgressive system proved to be an excellent natural laboratory to study the stratigraphic architecture and assess depositional trends and preservability over longer time scales (>100ka). It nevertheless demonstrates that no 'one-sizefits-all' analogue exists, but that various other analogues are needed to solve the complex puzzle which the Åre Formation resembles.

The middle Eocene interval at some Paris Basin localities was studied through high-resolution stratigraphy. Abundance data (499 species, 37 719 individuals) on the distribution of molluscs, collected at 12 shell beds of the middle...more

The middle Eocene interval at some Paris Basin localities was studied through high-resolution stratigraphy. Abundance data (499 species, 37 719 individuals) on the distribution of molluscs, collected at 12 shell beds of the middle Lutetian and lower Bartonian, formed the basis for a palaeoecological study. The middle Lutetian succession is subdivided into several elementary depositional sequences (EDS) interpreted as the product of relative sea-level change. Species-abundance distributions are better correlated with EDS than with geographical locality, suggesting that sea level played an important role in the distribution of palaeocommunities. Diversities were compared with analogous data from modern subtropical and warmtemperate intertidal and subtidal communities. We found that sea-level variation is responsible for a major change in the upper part of the middle Lutetian succession, leading from high-to low-diversity palaeocommunities. From base to top sampled palaeocommunities indicate a transition from high-energy and mesotrophic (EDS 2) to oligotrophic low-energy conditions of a sandy lower shoreface (EDS 4) to an upper shoreface (EDS 5 and lower Bartonian), the last with mangroves and a seagrass cover. Notwithstanding the Lutetian cooling, we found that subtropical conditions reached as far north as the Paris Basin. Our study suggests that climatic fluctuations might be obscured by facies control.

Fossil abundance data on foraminifer communities were collected in marginal marine sediments of the Pliocene Valdelsa succession, in Tuscany, Italy. This succession is organized in a hierarchy of elementary and composite depositional...more

Fossil abundance data on foraminifer communities were collected in marginal marine sediments of the Pliocene Valdelsa succession, in Tuscany, Italy. This succession is organized in a hierarchy of elementary and composite depositional sequences. Multivariate techniques allowed to analyse the dataset and reconstruct gradients in species distributions. Species-level data available on modern environmental distributions were used to reconstruct Pliocene environmental gradients and to infer absolute palaeodepths and palaeosalinities. Estimates were then compared with the sequencestratigraphic interpretation to check for consistency. The high-resolution stratigraphic framework allowed us to test the stability of foraminifer communities against ecological variations related to high-frequency glacio-eustatic cycles. The results confirm that fossil distributions of foraminifer species can be used as a fine tool to detect environmental change and that multivariate techniques allow their interpretation in terms of absolute variations of controlling parameters. Salinity is the main contributor to the sum of depth-related factors that regulate foraminifer distributions in coastal facies. In the same setting, nutrient levels and the presence of a sea grass cover are responsible for secondary changes in shallow-water distributions. Below the wave base, however, depth-related parameters other than salinity explain the largest variations. This study indicates that foraminifer communities are random associations of species that respond individualistically to environmental change. ᮀ Community stability , foraminiferal palaeoecology , gradient analysis , sequence stratigraphy .

Lithofacies analysis of the upper part of the Pliocene succession of the Valdelsa basin (central Italy) unravelled a number of depositional environments, ranging from alluvial plain to coastal, to marine. Strata are arranged in a...more

Lithofacies analysis of the upper part of the Pliocene succession of the Valdelsa basin (central Italy) unravelled a number of depositional environments, ranging from alluvial plain to coastal, to marine. Strata are arranged in a hierarchy of elementary and composite unconformitybounded units. A palaeoecological study of macro-(molluscs) and microfossils (pollen, dinocysts, foraminifera) allowed to finely reconstruct subenvironments within fine-grained terrestrial, coastal and marine deposits and thence to track the spatial and temporal change of physical conditions. The stacking pattern of sedimentary units highlights the lateral switching of onshore-offshore gradients and documents relative sea-level changes. These units are interpreted in a sequence stratigraphic framework. Elementary depositional sequences are arranged to form six composite depositional sequences, in turn encased within two major synthems. This hierarchy of unconformity-bounded sedimentary units suggests that sealevel variation has occurred at different time-frequencies. Glacio-eustasy and active tectonism are discussed as the main forcing factors regulating the different scales of sedimentary cyclicity.

Electrofacies and depositional systems of sequence penetrated in 'Ray' Field, Niger Delta were analyzed, using well log and 3-D seismic data, with a view to enable accurate prediction of source and reservoir rocks in the study area....more

Electrofacies and depositional systems of sequence penetrated in 'Ray' Field, Niger Delta were analyzed, using well log and 3-D seismic data, with a view to enable accurate prediction of source and reservoir rocks in the study area. Lithofacies were delineated through analysis of well logs using signatures of gamma ray, cross-plot of neutron-density logs and seismic facies analysis. The identified lithofacies were subjected to electrofacie analysis through diagnostic characteristics of gamma ray log indicative of a given depositional environment. Sands of different environments were subjected to seismic attribute and petrophysical analyses to assess the hydrocarbon potentials of such reservoirs. Results showed the presence of four lithofacies: Shale, Heterolithic, Shaly-Sandstone and Sandstone Facies. The electrofacies analysis revealed five depositional systems of Shoreface, prodelta, distributary, tidal and fluvial systems. Lateral variations of lithology and facies distribution, as well as presence of channels were imaged by seismic attribute. The sand units of the distributaries and tidal channels having thickness of 70 m and 65 m, and porosity of 16% and 24% respectively were viewed to have good quality for hydrocarbon reservoir.

in 2008 produced a highly decorated ivory handle of a clasp-knife. The object was found in Insula XIV in redeposited demolition layers and cannot, therefore, be closely dated. The handle depicts two fi ghting gladiators, a rare form in...more

in 2008 produced a highly decorated ivory handle of a clasp-knife. The object was found in Insula XIV in redeposited demolition layers and cannot, therefore, be closely dated. The handle depicts two fi ghting gladiators, a rare form in Britain and, indeed, in the rest of the Roman world, and merits publication in its own right. Insula XIV lies in the centre of the Roman town. Previous excavations have revealed the baths in Insula XIII to the west and a temple and shops in Insula IX to the north. The demolished buildings in Insula XIV were probably also shops. The scene on the handle depicts two types of gladiators fi ghting. The object is probably made of ivory since no bone or antler cancellous structures could be detected on the surface, as would have been the case if bone or antler had been used for such intricate carving. The ivory may have come from an Asiatic or African elephant, and would have been available through the Roman Empire trading network. The object measures 48 by 28 mm and has a maximum thickness of 14 mm. FIG. 4. Caerwent knife handle: (a) showing groove for the knife blade; (b) front depicting secutor on the left and retiarius on the right; (c) reverse. Scale 1:1.

Geostatistical analysis through computed mean vector azimuth (MVA) for the studied cross-bedding structures in oolitic limestones of the Wadi Al Qattarah Formation in the Wadi Al Aqar-NE Libya was done by using the recommended standard...more

Geostatistical analysis through computed mean vector azimuth (MVA) for the studied cross-bedding structures in oolitic limestones of the Wadi Al Qattarah Formation in the Wadi Al Aqar-NE Libya was done by using the recommended standard formula [MVA = tan-1(∑sinθ/ ∑cosθ)]. Graphic presentation of the studied cross-bedding directions has revealed a strong unidirectional orientation of cross-beds with minor reversals at some localities. In each unit, the primary mode is to the southeast, whereas the secondary mode is essentially asymmetrical about the mode. The strike of the cross-bedding sets in these deposits is normal to this trend. These data indicate that marine paleocurrent systems during the deposition of the oolitic limestones of the Wadi Al Qattarah Formation moved back and forth perpendicular to the shore and were probably the result of the strong ebb and flow of tides. The framework of these marine paleocurrents has suggested the inferred paleogeography of the Wadi Al Qattarah Formation in Wadi Al Aqar Quarry, in which the dispersal of the oolitic and skeletal limestone ridges in the southeast direction (ebb tide direction), changing to lagoonal settings in the northwestern and northeastern directions (flood tide direction).

The study area Gullebi Field is located on the southern edge of concession NC7A in the southcentral part of the intracratonic Ghadames Basin in northwestern Libya. The Tahara Formation which consists of sandstone and siltstone with shale...more

The study area Gullebi Field is located on the southern edge of concession NC7A in the southcentral part of the intracratonic Ghadames Basin in northwestern Libya. The Tahara Formation which consists of sandstone and siltstone with shale and iron-rich streaks interbedding is considered the main productive horizon in the study area. The stratigraphic framework identified from the analysis and interpretation of the subsurface data for the Late Devonian Tahara Formation, within the Gullebi Field, allow for the recognition of seven ( ) lithofacies based on core and wireline-log data which is; (1) dark grey micaceous bioturbated shale (offshore basinal marine environment), (2) parallel laminated silty sandstone and silty shale (deltaic complex environment), ( ) varicolored silty shale and bioturbated iron-rich shale (lagoonal to river influences environment), ( ) bioturbated sand and shale (beach environment), ( ) interlaminated shale and silty sandstone (coastal plain environment), ( ) massive sandstone and gravel (fluvial; river channel environment), ( ) rippled and fossiliferous sandstone (deltaic-beach environment). The Tahara sandstones can be classified as quartzarenites and sublitharenite in terms of their modal composition. Quartz grains constitute of an average about (86%) of the total sand grains, sparse feldspar grains account for about (2%) and rock fragments of an average (11%). Two types of porosity are recognized in the Tahara sandstones: (1) primary intergranular porosity (2) secondary porosity; dissolution of unstable grains was the dominant process to create secondary porosity. The diagenetic processes and their products may be identified to shed light on the sandstone quality variation of the Tahara Formation. A composite paragenetic sequence explaining diagenetic events through time for the Tahara sandstone of Gullebi Field can be proposed. Based on petrography data, identified diagenetic constituents, and proposed paragenetic sequence, three (3) possible reservoir quality types or associations can be identified for the Tahara sandstones in the Gullebi Field which are: 1-Good quality type of the Tahara sandstone was found to be associated with beach and deltaic complex lithofacies. 2-Medium quality type of the Tahara sandstone was found to be associated with fluvial channellithofacies. 3-Poor quality type of the Tahara sandstone was found to be associated with the lagoonal, coastal plain, and offshore marine lithofacies. The use of a diagenetic sequence integrated with depositional lithofacies represents an initial step in predicting regions of maximum enhanced and preserved porosity on the assessment of reservoir quality in the Tahara sandstones of the Gullebi Field.

The southern portion of the Venice lagoon contains a relatively thick (up to 20 m) Holocene sedimentary body that represents a detailed record of the formation and evolution of the lagoon. New very highresolution (VHR) seismic profiles...more

The southern portion of the Venice lagoon contains a relatively thick (up to 20 m) Holocene sedimentary body that represents a detailed record of the formation and evolution of the lagoon. New very highresolution (VHR) seismic profiles provided a detailed investigation on depositional geometries, internal bounding surfaces and stratal relationships. These informations, combined with core analysis, allowed the identification of large-to medium-scale sedimentary structures (e.g. dunes, point bars), the corresponding sedimentary environment, and of retrogradational and progradational trends. In addition, the availability of dense seismic network produced a 3D reconstruction of the southern lagoon and the recognition of the along-strike and dip variability of the stratal architecture. Three main seismic units (H1-H3), separated by key stratal surfaces (S1-S3), form the Holocene succession in the southern Venice lagoon. This succession is bounded at the base by the Pleistocene/ Holocene boundary (the surface S1), which consists of a surface of subaerial exposure locally subjected to river incision. The lower part of the Holocene succession (up to 13 m thick) consists of incised valley fills passing upward into lagoon and then shallow-marine sediments (Unit H1), and therefore shows a deepening-upward trend and a retrogradational stacking pattern. A prograding delta and adjacent shorelines, showing internal clinoforms downlapping onto the top of Unit H1 (the surface S2), form the middle part of the Holocene succession (Unit H2, up to 7.5 m thick). Unit H2 is interpreted as a result of a regressive phase started about 6 kyr BP and continued until recent time. The upper part of the Holocene succession (Unit H3) consists of lagoonal deposits, including tidal channel and tidal and subtidal flat sediments, that abruptly overlie Unit H2. Unit H3 is thought to represent a drowning of the area primarily due to human interventions that created rivers diversion and consequent delta abandonment during historical time.

The Late Maastrichtian–Danian phosphatic succession prevails as a deposit to the west of Rutbah region, Western Iraq. This is manifested through the lithostratigraphic sections of boreholes (K.H5\6 and K.H 5\8) drilled previously in the...more

The Late Maastrichtian–Danian phosphatic succession prevails as a deposit to the west of Rutbah region, Western Iraq. This is manifested through the lithostratigraphic sections of boreholes (K.H5\6 and K.H 5\8) drilled previously in the area. The succession is mainly composed of phosphate, shale, porcelanite, oyster and foraminiferal carbonate lithofacies belonging to Digma and Akashat formations. Three facies associations are distinguished during the study: the phosclast planktonic (FA1) that dominates the outer ramp, the phosclast foraminiferal (FA2) that dominates the mid ramp, and the quartz dolomitic phosclast (FA3) present in the inner ramp. These facies’ associations are differentiated into seventeen microfacies types. Microfacies analysis and fauna contents have shown gradual facies variation grading from a high energy inner ramp environment in the east to a low energy deep water ramp environment in the west.

The geologic time scale for the Cenozoic Era has been notably improved over the last decades by virtue of integrated stratigraphy, combining high-resolution astrochronologies, biostratigraphy and magnetostratigraphy with high-precision...more

The geologic time scale for the Cenozoic Era has been notably improved over the last decades by virtue of integrated stratigraphy, combining high-resolution astrochronologies, biostratigraphy and magnetostratigraphy with high-precision radioisotopic dates. However, the middle Eocene remains a weak link. The so-called "Eocene time scale gap" reflects the scarcity of suitable study sections with clear astronomically-forced variations in carbonate content, primarily because large parts of the oceans were starved of carbonate during the Eocene greenhouse. International Ocean Discovery Program (IODP) Expedition 369 cored a carbonate-rich sedimentary sequence of Eocene age in the Mentelle Basin (Site U1514, offshore southwest Australia). The sequence consists of nannofossil chalk and exhibits rhythmic clay content variability. Here, we show that IODP Site U1514 allows for the extraction of an astronomical signal and the construction of an Eocene astrochronology, using 3-cm resolution X-Ray fluorescence (XRF) core scans. The XRF-derived ratio between calcium and iron content (Ca/Fe) tracks the lithologic variability and serves as the basis for our U1514 astrochronology. We present a 16 million-year-long (40-56 Ma) nearly continuous history of Eocene sedimentation with variations paced by eccentricity and obliquity. We supplement the high-resolution XRF data with low-resolution bulk carbon and oxygen isotopes, recording the long-term cooling trend from the Paleocene-Eocene Thermal Maximum (PETM -ca. 56 Ma) into the middle Eocene (ca. 40 Ma). Our early Eocene astrochronology corroborates existing chronologies based on deep-sea sites and Italian land sections. For the middle Eocene, the sedimentological record at U1514 provides a single-site geochemical backbone and thus offers a further step towards a fully integrated Cenozoic geologic time scale at orbital resolution.

His tasks at CES involve integrated field studies in mature petroleum regions of the Gulf Coast as well as identifying and transferring upstream technologies to independent operators through the programs of the Petroleum Technology...more

His tasks at CES involve integrated field studies in mature petroleum regions of the Gulf Coast as well as identifying and transferring upstream technologies to independent operators through the programs of the Petroleum Technology Transfer Council.

There is a limited understanding of the spatial linkage between cementation processes in shoreface/coastal plain successions and those operating in distal offshore successions. To address this, an integrated sedimentological, sequence...more

There is a limited understanding of the spatial linkage between cementation processes in shoreface/coastal plain successions and those operating in distal offshore successions. To address this, an integrated sedimentological, sequence stratigraphic and diagenetic study was undertaken on a distal shallow-marine succession, the Upper Cretaceous Kenilworth Member Book, Cliffs, Utah, USA. Laterally extensive carbonate cement is the most volumetrically significant diagenetic feature. It constitutes up to 55 vol.% of the distal lower-shoreface sandstone and sandy siltstone units beneath major flooding surfaces. During rising relative sea-level major flooding events resulted in low sedimentation, which extended residence time of sediments in early diagenetic zones and promoted enhanced cementation beneath these boundaries. Carbonate for early calcite cements was probably derived from sulphate reduction, marine water and oxidation of organic matter. Stable-isotopic composition of later ankerite (δ 18 O ∼-11.9 to -6.0‰ VDPB, δ 13 C ∼-4.5 to -0.3‰ VDPB) suggests precipitation during progressive burial (c. 1.7 to 3.4 km, 72 to 122 °C) from evolved marine fluids. The carbonate and other mineralizing solutes were derived, increasingly with burial, from decarboxylation of organic matter and clay mineral transformations in adjacent siltstones and shales. These interbedded, overlying and underlying facies provided an important source of mineralizing solutes that influenced the extent of pervasive cementation during burial. The combination of stratigraphic and lithofacies control resulted in laterally extensive cements that differ to shoreface successions, although are similar in form to those described for many offshore mudstone-dominated successions. Limited early concretionary ferroan dolomite beneath the expression of the sequence boundary and some flooding surfaces, however, suggests cementation by meteoric fluids at times of relative sea-level lowstand. Similar processes have been demonstrated in more proximal successions in the Book Cliffs.

The sequence stratigraphic model, though no longer focused on eustasy and accommodation, has been up until recently based largely on observation and interpretation of outcrop and subsurface data. This approach may be restrictive if the...more

The sequence stratigraphic model, though no longer focused on eustasy and accommodation, has been up until recently based largely on observation and interpretation of outcrop and subsurface data. This approach may be restrictive if the current model places limits on what is observed and how observations are interpreted.To make progress in our understanding of strata, the sequence stratigraphic model and method should be tested against and fully incorporate theoretical and experimental results that provide new knowledge of (1) autogenesis, (2) intrinsic stratigraphic responses, (3) alluvial grade, and (4) scales appropriate to individual depositional systems evolving with relative sea level changes. More extensive Inclusion of analogue and numerical experimental results could lead to significant modification and refinement of existing sequence stratigraphic models. The emergence of the seismic and sequence stratigraphy method and model in the 1970s, is often described as a revolution in the science of stratigraphy, and has been compared to the origination and establishment of plate tectonics theory (e.g. . Certainly, sequence stratigraphy, especially through the use of seismic data, has had a huge impact on the study and interpretation of strata in the late 20th century. It showed that sedimentary strata imaged on seismic data were commonly organized into discrete, repetitive unconformity bounded onlapping-to-downlapping depositional sequences The early model utilised long-standing ideas that made eustasythe best-known repetitive driving mechanismto create sequences. However, a simple eustasy-based interpretation of the repetitive stratal packages attracted criticism (e.g.

3D reservoir characterizations o f analogues based on outcrop studies provide geological informa tion that can be used for reducing uncertainty in subsurface reservoir modelling to predict interwell areas. 3D reservoir-scale models o f a...more

3D reservoir characterizations o f analogues based on outcrop studies provide geological informa tion that can be used for reducing uncertainty in subsurface reservoir modelling to predict interwell areas. 3D reservoir-scale models o f a 133 m thick transgressive-regressive sequence (Vilomara com posite sequence), in the Sant Llorenç del Munt fan-delta complex (Eocene, Ebro foreland basin), reproduce heterogeneity scales which potentially influence flow simulation predictions. Three scales were recognized and modelled: (a) transgressive and regressive tracts in which the sedimentary record is structured; (b) stacking and interfingering of facies belts and (c) sedimentary bodies which provide sedimentological variability along facies belts. In order to solve the different stacking trend o f transgressive and regressive tracts by using different modelling strategies, models were compart mentalized into several sections by means o f modelling bounding surfaces (maximum regression and flooding surfaces). The depositional trend o f facies belts for each tract was reproduced consid ering the stacking angle and interfingering measures obtained from outcrop studies, while the last modelling step in this work describes the geometry, arrangement and spatial relations o f sedimen tary bodies observed in field. All these models are stochastic simulations built applying different statistics algorithms provided by Roxar Reservoir Modelling System.

This study was carried out to better understand the geology and depositional environments of rock units in the Ede-Oballa - Orba axis of southeastern Nigeria. The integration of outcrop data, facies and sedimentological analyses aided...more

This study was carried out to better understand the geology and depositional environments of rock units in the Ede-Oballa - Orba  axis of southeastern Nigeria. The integration of outcrop data, facies and sedimentological analyses aided the interpretation of the depositional setting of the sediment packages. Geologic mapping showed that the area is underlain by the Ajali Formation and Nsukka Formation of the Anambra Basin. Three outcropping lithologies were identified namely: sandstone, siltstone and mudstone. Facies analysis revealed eight (8) lithofacies namely: Conglomeritic Sandstone (CS) facies, Structureless sandstone (Ss) facies, Heterolith (H) facies, Siltstone (Si) facies, Mudstone (Fm) facies, Interbedded Sandstone and Mudstone (SM) facies, Cross-bedded sandstone (Cbs) facies and Ferruginized Sandstone (IS) facies. These lithofacies were further grouped into four facies associations; FA1 - prodelta deposits, FA2 - delta front deposits, FA3 - distributary channel-fill deposits and FA4 - fluvial channel deposits. Result from sieve analysis data indicates that the sands are generally medium to coarse-grained, but dominantly medium-grained, poorly to moderately sorted, due to fluctuations in energy of depositional agent, albeit with dominance of high energy. Bivariate discriminant plots of Mean vs Sorting and Sorting vs Skewness indicate fluvial – shallow marine environments. In addition, paleocurrent analysis showed unimodal, low variance pattern and vector strength of (0.94) suggesting fluvial environment of deposition. Overall, the rock units of the study area were deposited generally within the environments that span from continental through marginal marine setting.

This study firstly presented that the Carboniferous-Permian sequences along the western margin of the Sibumasu Block in Myanmar are characterised by Mississippian Cimmerian-type fauna, Kungurian admixtures of both Cathaysian and Gondwanan...more

This study firstly presented that the Carboniferous-Permian sequences along the western margin of the Sibumasu Block in Myanmar are characterised by Mississippian Cimmerian-type fauna, Kungurian admixtures of both Cathaysian and Gondwanan taxa, Cathaysian-affinity flora, and Guadalupian warm-water organisms. These biotas represent different paleolatitude settings within the Cimmerian continents and distinct drifting histories. The Asselian to Sakmarian glaciomarine deposits in the lower part of the Mergui Group contain typical Gondwana-type cold-water faunas found in other parts of the Sibumasu, but these have not yet been observed in the Shan Scarp zone of Myanmar. Due to the absence of Pennsylvanian strata, the plant fossil-bearing Mwedaw Beds overlie the Tournaisian-Visean Loikaw Beds and are underlain by the Thitispin Formation in the Shan Plateau zone. The Permian sequences are most clearly observed in the Shan Scarp zone, which lacks Carboniferous strata.

In the book, Restless Tides of Time, Sea-Level Change: Past, Present and Prescient, Bilal Haq invites readers on a sweeping odyssey across Earth's watery epochs, a narrative distilled from decades of research, weaving scientific...more

In the book, Restless Tides of Time, Sea-Level Change: Past, Present and Prescient, Bilal Haq invites readers on a sweeping odyssey across Earth's watery epochs, a narrative distilled from decades of research, weaving scientific exactitude with story-teller's flair. From the primeval watery stirrings of the Precambrian to the Anthropocene's rapidly shifting shorelines, he breathes life into our planet's continuously transformational relationship with its oceans. Haq unravels the forces – tectonic, climatic, and cosmic – that sculpted coastlines and drowned continents through time, showing us not only how we measure the oceans' pulse, but what it tells us about our past and also our future. Engaging both specialists and general readers, this book reveals the deep interdependence between humanity and the oceans. In eleven chapters, Haq explores how our understanding of the oceans has grown – from early observations in the Age of Reason to today and beyond. Restless Tides of Time is both a story of Earth's ever-evolving, malleable oceans and a reminder that our own fate is inextricably bound to the movement of the tides.

Bilal U. Haq – geoscientist, naturalist, and poet – has dedicated his research to uncovering the deep rhythms of the oceans, tracing the dramatic rise and fall of sea levels across the Phanerozoic Eon, and understanding the powerful forces that have shaped our planet's highly mutable land-and sea-scapes. A member of the European Academy of Sciences, Haq is a laureate of the Prestwich Prize conferred by Société Géologique de France, and a recipient of Geological Society of America's International Distinguished Career Award. These accolades recognized not only the extensive scope of his scientific contributions –encompassing vast temporal and geographic scales – but also his sustained commitment to communicating the dynamic history of Earth's oceans, a critical component of the planet's geological narrative, to both scientific and broader audiences.

The Shiranish Formation represents one of the most important fractured reservoirs in northern Iraq. In this work, the petrophysical properties of the formation have been fully characterised using microscopy, core analysis, and well log...more

The Shiranish Formation represents one of the most important fractured reservoirs in northern Iraq. In this work, the petrophysical properties of the formation have been fully characterised using microscopy, core analysis, and well log analysis using conventional methods as well as new quantitative diagenetic approaches. During this work we have developed methods to quantify a petrophysical heterogeneity index (χ), reservoir quality indicator (RQI), and fracture effect index (FEI) for each of the stratigraphic units of the formation. The FEI was calculated by dividing the difference between the mean permeability of the wireline log data and the mean permeability of the unfractured core plug samples by the difference between the mean porosity of the wireline log data and the mean porosity of the unfractured core plug samples. This study shows that the Shiranish Formation has a fracturing pore system in all the characterised units, but it is particularly well developed in U.4, which shows the best reservoir quality (A and B). The new methods developed in this study can be applied to any carbonate formation to provide a trustworthy way to obtain a reservoir quality indicator linked to the petrophysical heterogeneity of the studied formation.

Aqra Formation is a shallow marine deposit of the late-Cretaceous sedimentary cycle. According to the field lithological description, the two studied sections of the Aqra Formation are subdivided into three units. Based on...more

Aqra Formation is a shallow marine deposit of the late-Cretaceous sedimentary cycle. According to the field lithological description, the two studied sections of the Aqra Formation are subdivided into three units. Based on sedimentological characteristics and fossils assemblage eleven facies have been recognized in both studied sections, their alternated association points to a wide range of depositional environments extended from tidal flat, back reef, reef, to fore-reef. Based on the fossil's appearance, the studied sections comprised two fossils biozone {Orbitoides media zone (part) and Liftusia morgani zone}, it is age determined to be late Campanian-Early Maastrictian in both studied sections. Sequence stratigraphic analysis, as calibrated by sedimentary facies and biostratigraphy delineated one sequence (Aqra sequence 1) of 2nd order, and their MFI correlation result with MFS studies in the Arabian platform indicated to maximum flooding stage dominated on the Arabian plate at the Latest Campanian.

As the global landscape transitions into a new epoch marked by a perceived “acceleration of history”, emerging paradigms are increasingly embraced by both policymakers and analysts in a concerted effort to articulate and guide...more

As the global landscape transitions into a new epoch marked by a perceived “acceleration of history”, emerging paradigms are increasingly embraced by both policymakers and analysts in a concerted effort to articulate and guide contemporary international relations. Following the dissolution of the USSR and a period of overconfidence among the former Western bloc, the era often referred to as the “American century” has now concluded. This term, introduced by American media mogul Henry Luce in 1940, evokes a complex legacy. It is not our current objective to evaluate whether the twentieth century warranted this designation or if the early years of the twenty-first century have provided sufficient justification for such a label. What is critical to acknowledge is the significant impact these concepts have on both the analysis and formulation of policy. Despite the hesitance exhibited by China and Russia, the concept of the Indo-Pacific gained prominence when Shinzo Abe returned to power and successfully persuaded U.S. leadership of its importance. This development elucidates why the U.S. Indo-Pacific strategy does not encompass the entirety of the Indian Ocean but rather integrates India into an already established Asia–Pacific framework of interest.

Alberta Geological Survey completed field programs in June 2007 and October 2008 near Cardston, Taber and Fort McLeod. We described outcrops of Upper Cretaceous and Tertiary formations in the field, took radioactivity measurements onsite,...more

Alberta Geological Survey completed field programs in June 2007 and October 2008 near Cardston, Taber and Fort McLeod. We described outcrops of Upper Cretaceous and Tertiary formations in the field, took radioactivity measurements onsite, and collected 122 samples for determination of multiple elements. Representative thin sections were prepared and detailed petrographic descriptions, including point counts, were made. We conducted a radiometric survey along the St. Mary, Waterton and Oldman rivers. The most notable result of the 2007 and 2008 field programs was the discovery of a new radioactive occurrence, consisting of anomalous uranium content (158 ppm) in the siltstones of the Willow Creek Formation along the Oldman River. An automated evaluation of tens of thousands of digital logs from oil and gas wells, and subsequent detailed analysis of 1800 well logs, outlined areas for future assessment. We selected anomalous gammaray intervals in the upper 550 m for determination of rock type and formation. Eighty-two per cent of the high-gamma intervals occur within shaly units with a high organic content (e.g., Base of Fish Scales and Second White Specks formations). Clusters of wells with high gamma readings in sandstone occur in NTS areas 82O, 83G, 84D and 83O. In the Claresholm area, multiple wells with high gamma readings in sandstones of the Willow Creek and St. Mary River formations occur within the upper 500 m. Testing drill cuttings from oil and gas wells that cover radioactive intervals was unable to confirm the source rocks for the radioactive anomalies but provided insight into the rock types of these intervals. We collected 109 and 18 rock samples during 2007 and 2008, respectively. All samples were analyzed using inductively coupled plasma (ICP-OES) following HNO 3 /HCl partial digestion and HF/HNO 3 /HClO 4 total digestion. Uranium was also analyzed by the more sensitive fluorimetry method.

This project was initiated by Dr. Reg Olson (AGS), whose enthusiasm and experience in uranium exploration were invaluable in both field and office work. Dr. Olson also played a key role in establishing contacts with industry, organizing...more

This project was initiated by Dr. Reg Olson (AGS), whose enthusiasm and experience in uranium exploration were invaluable in both field and office work. Dr. Olson also played a key role in establishing contacts with industry, organizing and carrying out field projects, and giving technical advice throughout the year. Many of our AGS colleagues contributed their knowledge and expert advice to the project. We thank Christina Pana for advice on stratigraphy and for help with deciphering geophysical logs for oil and gas wells. Dr. Dean Rokosh provided advice on applicability and use of available digital datasets. Andrew Beaton advised on regional geology of the study area. Tony Lemay and Dustin Shauer helped with advice on hydrogeology of the area. Roger Paulen contributed advice on quaternary geology of the region. Dan Magee created many of the figures of the report. Dr. Shahin Dashtgard helped with thin section descriptions. Mary Ann Barnes provided logistical and business support. Joan Waters and Dennis Chao advised on GIS compilation. Gisela Hippolt-Squair helped with editing and compilation of the final report. Hanne Csanyi and Linda White provided excellent library support. We are grateful to the local landowners, including private individuals and Hutterite colonies, who kindly agreed to allow access to study outcrops, shared local knowledge with us, and agreed to and facilitated sampling of the water wells. We are grateful to exploration companies actively working in the area and their consultants: Firestone Ventures Inc., North American Gem Inc., Strathmore Minerals Corp. and consultants Glen Hartley, Bob Ryziuk and Lester Vanhill for sharing knowledge and ideas about uranium potential of southern Alberta. We gratefully acknowledge Bob Ryziuk for supplying us with a sample of high-grade organic material from Willow Creek Formation. We thank our Geological Survey of Canada (GSC) colleagues for active participation in the project and scientific editing of this report. Dr. Charlie Jefferson (GSC Ottawa) participated in fieldwork, technical discussions and organized financial support for the project. Dr. Tony Hamblin (GSC Calgary) participated in both the fieldwork and technical discussions and gave invaluable advice on stratigraphy and lithology of the study area.

This paper aims to present an analytic reading of the book Amar, verbo intransitivo -idílio (1927), by Mário de Andrade, emphasizing the mechanisms of construction of the main character -Fräulein/Elza, inside a context of production and...more

This paper aims to present an analytic reading of the book Amar, verbo intransitivo -idílio (1927), by Mário de Andrade, emphasizing the mechanisms of construction of the main character -Fräulein/Elza, inside a context of production and reception of the work. It also composes this paper a study about the poetic of Mário de Andrade, more specifically in this work, and also the historical course of the Brazilian Modernism where it presents the ninety years of the Modern Art Week and its results. To that end, we adopted as a methodological procedure, a research of bibliographical approach, that is based upon reflections of Antonio Candido about the construction of the character in the novel, and also the discussions of this narrative category presented by Reis & Lopes and Brait. To talk about the Modern Art Week it were used texts of Bosi, Candido and Castello. To what refers to the author and this book other research sources were used, such as Lopez, Moisés, Andrade, Moraes, Carvalho among others.

Twenty-two ammonite species are identified in the upper Albian Mortoniceras (Subschloenbachia) rostratum, Mortoniceras (Subschloenbachia) perinflatum and Stoliczkaia (Shumarinaia) africana Zones, and in the lower Cenomanian Mantelliceras...more

Twenty-two ammonite species are identified in the upper Albian Mortoniceras (Subschloenbachia) rostratum, Mortoniceras (Subschloenbachia) perinflatum and Stoliczkaia (Shumarinaia) africana Zones, and in the lower Cenomanian Mantelliceras mantelli Zone. The species Placenticeras Saadensis Thomas and Peron, 1890 is revised, including Engonoceras Thomasi Pervinquière, 1907, and is placed within the genus Hypengonoceras Spath, 1922. This accurate biostratigraphic framework allowed to evidence, at the Albian-Cenomanian transition (S. (S.) africana Zone), a significant sea level drop, responsible for emergence and erosion to the SE, and for deposition of a Lowstand wedge to the NW, fed by erosional channels on the shelf slope. Plesiosaur remains found in the upper Albian series (base of M. (S.) rostratum Zone) represent one of the few elasmosaurids known worldwide in the Albian, and the first plesiosaurian reported from Tunisia.

Wireline logs and biostratigraphic data were integrated to attempt the sequence stratigraphy of "XY field" onshore Niger Delta Basin which revealed three depositional sequences. Four sequence boundaries and three maximum flooding surfaces...more

Wireline logs and biostratigraphic data were integrated to attempt the sequence stratigraphy of "XY field" onshore Niger Delta Basin which revealed three depositional sequences. Four sequence boundaries and three maximum flooding surfaces dated (17.7, 16.7, 15.5, and 13.1Ma) and (17.4, 15.9, 15.0 Ma) respectively were identified in both Wells. The delineated sequences comprised Lowstand Systems Tracts (LST), Transgressive Systems Tracts (TST) and Highstand Systems Tracts (HST), which reflect depositional systems deposited during different phases of base level changes. The sands of LST and HST show good reservoir qualities while the shales of the TSTs could form potential reservoir seals. Integration of lithofacies and biofacies data suggests that the depositional environments ranges from transitional to Outer Neritic environment.

Palynological and paleoenvironmental study of outcrops exposed around Bende and Umuahia areas were carried out to re-evaluate its age and reconstruct the environment of deposition. Palynological analysis of the sediments was done by using...more

Palynological and paleoenvironmental study of outcrops exposed around Bende and Umuahia areas were carried out to re-evaluate its age and reconstruct the environment of deposition. Palynological analysis of the sediments was done by using conventional method of 40% concentrated Hydrofluoric acid maceration to determine the age and paleoenvironment of the area. Lithological units encountered were carbonaceous shale, sandstones, mudstones and limestone. Age determination/correlation was based on occurrence of stratigraphically significant age diagnostic palynomorph assemblages. Imo Formation was dated Middle – Late Paleocene with the following index fossils assemblage, Proxapertites operculatus, Echitriporites trianguliformis, Retibrevitricolpites triagulatus, Spinizonocolpites baculatus, Scabratriporites simpliformis, Mauritidiites crassibaculatus, Bombacidites sp., and Grimsdalea polygonalis . Ameki Formation was assigned Early-Middle Eocene based on Monoporites annulatus, Proxapert...

Early and Middle Miocene microfossil-rich sediments have allowed better biostratigraphy of the Oued Rhiou geological series (southern margin of Lower Chelif Basin). Calibration between Calcareous nannoplankton (Helicosphaera ampliaperta,...more

Early and Middle Miocene microfossil-rich sediments have allowed better biostratigraphy of the Oued Rhiou geological series (southern margin of Lower Chelif Basin). Calibration between Calcareous nannoplankton (Helicosphaera ampliaperta, Sphenolithus heteromorphus) and Planktonic foraminifera (Globigerinoides trilobus, Gs. sicanus without Praeorbulina) biozone markers of the Oued Taberket and Sidi El Rhorb sections corresponds to the latest Burdigalian. The Oued Boutelis Langhian age is based upon Globorotalia siakensis, Praeorbulina glomerosa curva and P. glomerosa glomerosa, associated with S. heteromorphus, H. ampliaperta and ostracods. Through successive biozones (upper N9/NN4 to lower N10), this last section reaches late Langhian, which includes the Burdigalian-Langhian boundary (biozones N8/NN4). This boundary correlates well with the generally accepted one (15.974 Ma). A large subsidence furrow in the SW piedmont of the Ouarsenis is responsible for this sedimentation. The process of its filling during the latest Burdigalian to late Langhian is characterized by transgressive-regressive sequences correlated with the fluctuations of the eustatic cycles TB2.3 and TB2.4. These illustrate three marine sedimentation phases separated by two discontinuities: intra-latest Burdigalian and Burdigalian-Langhian boundary. The first (deep) phase tends towards a coastal detritic environment, the second being coastal sub-to mid-littoral high-energy detritic, illustrating a clear eustatic and tectonic evolution, evidence of significant subsidence. A hyperpycnal delta initiated the third phase, evolving gradually into a deep environment. The characteristics of the paleontological environment indicate warm climatic conditions during the latest Burdigalian to Langhian in the northern Algerian basins, admitting mangroves on the coasts. These thermal conditions suggest the same characteristics of the mid-Miocene climatic optimum.

The foraminiferal contents of the Miocene deposits exposed in two sections in Wadi Bali and Wadi Kharaza, Gebel Abu Shaar El Qibli plateau, Western side of the Gulf of Suez, Egypt were carefully studied for their benthic and planktonic...more

The foraminiferal contents of the Miocene deposits exposed in two sections in Wadi Bali and Wadi Kharaza, Gebel Abu Shaar El Qibli plateau, Western side of the Gulf of Suez, Egypt were carefully studied for their benthic and planktonic foraminiferal content. Based on their lithofacies variations and microfaunal content, three rock units were studied, from base to top as follows: Abu Gerfan Formation, polymictic conglomerates (Early Miocene, Aquitanian), the overlying Gharamul Formation (carbonate and mixed siliciclastic-carbonate) (Middle Miocene, Burdigalian to Lnghian), and evaporates of Gemsa Formation (Middle Miocene, Serravallian age) are reported. Detailed smaller, larger and planktonic foraminiferal investigations led to the recognition of three foraminiferal zones from base to top: 1) Miogypsina complnata / Nonion granosus Zone (Zone SBZ 24), comprising the Abu Gerfan Formation that ascribed to Early Miocene Aquitanian age, 2) Miogypsina globulina zone (SBZ 25) representing the lower unit of Gharamul Formation, and correlated with the Early Miocene, Burdigalian age and lastly 3) Borelis melo melo Zone (SBZ 26) of Middle Miocene, Langhian age covering the upper part of Gharamul Formation. The Middle Miocene interval of Gharamul Formation is ascribed to the Langhian for first time where Operculina complanata (Defrance) and Borelis melo melo (Fichtel and Moll) are the main time-specific diagnostic taxa recognized in this interval. For the first time, planktonic foraminifera are documented from the Gharamul Formation in Gebel Abu Shaar El Qibli plateau being characterized by the occurrence of planktonic foraminifera such as Globigerina praebulloides, Globigerina ciperoensis, Globigerinoides altiaperturus, Globigerinoides trilobus and Globigerinoides subquadratus. This association characterises the Borelis melo melo interval Zone. The variation in lithology and foraminiferal assemblages will be discussed here and reflects the variety of environmental settings characterizing the studied Miocene sequence, indicating an overall shallowing-upward trend, from continental to subeqous fan delta facies of Abu Gerfan Formation to platform reefal facies and restricted lagoon-salina conditions represented by evaporites of Gemsa Formation.

The aim of this study is to analyze the assemblage of trilobites in the Silurian sequences of Iran by exploring stratigraphic section of the Silurian Niur Formation (Asadli section). Based on comprehensive field studies and laboratory...more

The aim of this study is to analyze the assemblage of trilobites in the Silurian sequences of Iran by exploring stratigraphic section of the Silurian Niur Formation (Asadli section).  Based on comprehensive field studies and laboratory investigations three Trilobite genera were identified in the study area including Calymene blumenbachii, Gravicalymene convolva, Dalmanites brevigladiolus and Calymene sp. according to this trilobite assemblage a Rhuddanian to Telychian stages (Llandovery) is suggested for deposition of the study strata. The recognized trilobite fauna will be used as a base for future geological studies on the Silurian strata in Kopeh-Dagh Basin. This is the first report of trilobites from the Silurian (Llandovery) Niur Formation in Asadli section, north- east, Iran.

Esse artigo apresenta os resultados obtidos durante as atividades de salvamento arqueológico para o Programa de Gestão do Patrimônio Arqueológico do empreendimento Loteamento Residencial Brisas do Lago, sendo este ume estudo preventivo,...more

Esse artigo apresenta os resultados obtidos durante as atividades de salvamento arqueológico para o Programa de Gestão do Patrimônio Arqueológico do empreendimento Loteamento Residencial Brisas do Lago, sendo este ume estudo preventivo, realizado no município de Iranduba, estado do Amazonas, autorizado por meio da Portaria n.º 25 de 25 de abril de 2024. A pesquisa objetivou o desenvolvimento de atividades que visaram minimizar o impacto das ações de implantação das obras do empreendimento, bem como compreender o contexto arqueológico existente nessa área. Como resultado das ações executadas em campo, foram coletados um acervo de 2580 vestígios arqueológicos.

The north Bohemian Cretaceous (Bohemian Cretaceous Basin; Czech Republic) is located between the northern temperate areas and the Tethys. As a gateway to the Tethys, lithology, fauna and integrated stratigraphy (litho-, bio-, event,...more

The north Bohemian Cretaceous (Bohemian Cretaceous Basin; Czech Republic) is located between the northern temperate areas and the Tethys. As a gateway to the Tethys, lithology, fauna and integrated stratigraphy (litho-, bio-, event, sequence, stable isotope stratigraphy) of the Upper Turonian succession in the U ´pohlavy working quarry are described. Due to a large hiatus, the d 13 C curve cannot be used for stratigraphic purposes at the base of the section. Up-section, the curve exhibits the well-known middle Upper Turonian positive excursion. Biostratigraphic and sequence stratigraphic subdivisions permit good correlation with other European Cretaceous basins. The inoceramid bivalve assemblage enables correlation with the US Western Interior. Palaeoceanographically, a positive peak in the d 18 O curve above the hiatus indicates the upper part of the Late Turonian cooling event observed in other areas. The cooling was accompanied by a southward shift of a cool/temperate oceanic biosedimentary system, expressed by the sudden turnover from siliciclastic towards pelagic carbonate deposition. It is associated with the establishment of presumed oligotrophic conditions in the immediate vicinity of the West Sudetic Island, as indicated by the sudden decrease of macrofaunal abundance and diversity.

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to...more

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to establish nannofossil biozonation and determine the age of the study intervals. Lithologically, the examined sequences consist of grey shales, siltstones, and mudstones, with intercalations of thin-bedded sandstones. The analysis revealed a moderately diverse assemblage of calcareous nannofossils. Nannofossil zones were identified based on the first and last occurrences of easily recognizable marker species and their relative abundances. These zones facilitated the age determination of the sequences, which range from the Early Miocene to the Middle Miocene. Key marker species and diagnostic assemblages, including Sphenolithus abies, Sphenolithus heteromorphus and Discoaster drugii, were used to assign ages from NN5 to NN3, according to the classic zonation scheme of Martini (1971).

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to...more

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to establish nannofossil biozonation and determine the age of the study intervals. Lithologically, the examined sequences consist of grey shales, siltstones, and mudstones, with intercalations of thin-bedded sandstones. The analysis revealed a moderately diverse assemblage of calcareous nannofossils. Nannofossil zones were identified based on the first and last occurrences of easily recognizable marker species and their relative abundances. These zones facilitated the age determination of the sequences, which range from the Early Miocene to the Middle Miocene. Key marker species and diagnostic assemblages, including Sphenolithus abies, Sphenolithus heteromorphus and Discoaster drugii, were used to assign ages from NN5 to NN3, according to the classic zonation scheme of .

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to...more

Calcareous nannofossil biostratigraphic analysis was conducted on 20 ditch cutting samples from the IZA-1 well, located in the offshore deep-water area of the Niger Delta. The study employed the pipette strew preparation method to establish nannofossil biozonation and determine the age of the study intervals. Lithologically, the examined sequences consist of grey shales, siltstones, and mudstones, with intercalations of thin-bedded sandstones. The analysis revealed a moderately diverse assemblage of calcareous nannofossils. Nannofossil zones were identified based on the first and last occurrences of easily recognizable marker species and their relative abundances. These zones facilitated the age determination of the sequences, which range from the Early Miocene to the Middle Miocene. Key marker species and diagnostic assemblages, including Sphenolithus abies, Sphenolithus heteromorphus and Discoaster drugii, were used to assign ages from NN5 to NN3, according to the classic zonation scheme of .