Hasil untuk "Stratigraphy"

T. M. Herriott, J. L. Crowley, M. A. Wartes et al.

<p>Sound geologic reasoning underpins detrital zircon (DZ) maximum depositional ages (MDAs) via the principle of inclusions, although interpreting in situ U–Pb date distributions requires many geologically, analytically, and statistically driven decisions. Existing research highlights strengths and challenges of various algorithm approaches to deriving MDAs from DZ dates, yet community consensus on best practices remains elusive. Here, we first address new laser ablation–inductively coupled plasma mass spectrometry (LA-ICPMS) and chemical abrasion–isotope dilution–thermal ionization mass spectrometry (CA-ID-TIMS) U–Pb geochronology for five DZ samples from a <span class="inline-formula">∼1</span> km thick section of mid-Cretaceous strata in Alaska's Colville foreland basin. Youthful DZ yields are extremely sparse, and the MDAs are <span class="inline-formula"><i>n</i>=1</span>. LA-ICPMS and CA-ID-TIMS dates from the same grains (i.e., tandem dating) adhere to a uniform pattern: laser ablation dates are younger than paired isotope dilution dates, with in situ offsets ranging from <span class="inline-formula">−0.3</span> % to <span class="inline-formula">−6.4</span> %. Existing biostratigraphic constraints suggest a <span class="inline-formula">∼110</span>–94 Ma sedimentation window for the sampled section, but the CA-ID-TIMS MDAs reduce by <span class="inline-formula">∼8.5</span> Myr the maximum geologic time recorded by the stratigraphy. A simple age–depth analysis incorporating the CA-ID-TIMS MDAs and correlation of a new CA-ID-TIMS tephra zircon age yields geologically reasonable minimum stratigraphic accumulation rates, but an LA-ICPMS-based interpretation would render an improbable and inaccurate chronostratigraphy. We then explore the new tandem data and two previously published Mesozoic tandem DZ datasets for their broader MDA research implications, focusing on tandem-date pair relations and youthful-population sampling densities rather than conducting the typical MDA algorithm output assessment. Percent-offset plots document impactful (<span class="inline-formula">∼2 <i>%</i></span>–3 % on average) and pervasive (<span class="inline-formula">∼87 <i>%</i></span>–100 % of pairs per study) young bias for the laser ablation dates, likely reflecting a complex combination of analytical dispersion, low-temperature Pb loss, and matrix effects, which are topics we review in detail. Deconvolving offset sources without elaborate geochronologic experiments is difficult, but our tandem-date analysis provides critical context, and follow-up CA-ID-TIMS can diminish or eliminate analytical, systematic, and geologic offset sources. We also (1) redefine the reference value for MDA accuracy as the crystallization age of the youngest analyzed DZ population in a sample and (2) reframe LA-ICPMS-based DZ MDA algorithm evaluations around validity – how capable are the metrics of accurately measuring what they are intended to measure? – rather than MDA benchmarking by existing age constraints. These new perspectives follow straightforward geochronologic and stratigraphic principles, and our synthesis intends to identify and clarify opportunities to further refine DZ MDA research.</p>

L. Weerachai, L. Weerachai, A. Chitnarin et al.

<p>This study investigates the lithostratigraphy and palaeoenvironmental conditions of Holocene sediments from five boreholes in the Lower Central Plain of Thailand, with a focus on ostracod assemblages and sedimentary facies. Lithostratigraphic analyses identified five lithologic units belonging to two distinct facies representing tidal–intertidal and prodelta environments. Ostracod analysis identified 15 species, representing genera found in the Indo-Pacific and South China regions, including <i>Neocyprideis</i>, <i>Sinocytheridea</i>, <i>Propontocypris</i>, <i>Hemicytheridea</i>, <i>Keijella</i>, <i>Neomonoceratina</i>, <i>Aglaiocypris</i>, <i>Lankacythere</i>, <i>Cytherella</i>, and <i>Stigmatocythere</i>. Ostracods recovered from tidal–intertidal facies suggest transportation from shallow marine environments to tidal channels, while the greater diversity in prodelta facies indicates a more stable and favourable environment. <i>Neocyprideis agilis</i> was found abundantly in the samples, marking the oldest known record of this species in the South China Sea during the Late Holocene. The facies succession is characterised by a fining-upward trend, reflecting a shift from Lower–Middle Holocene tidal channels and intertidal flats to a Late Holocene prodelta system. These findings clarify the depositional history of the Lower Central Plain, demonstrating how tidal and marine processes shaped a dynamic, tide-dominated palaeoenvironment throughout the Holocene.</p>

Gemma Aiello

We built a regional geological section founded upon the assessment of a seismic line in the Volturno basin, which is situated on the northern Campania continental shelf of the Tyrrhenian margin of Southern Italy. This section has been integrated with multichannel seismic data of Zone E (ViDEPI project) to highlight its relationships with the Massico structure. In the Volturno basin, there are four Pleistocene to Holocene units, recognized based on seismic analysis lie above deep seismo-stratigraphic units, related to Campania Latium carbonate platform and The Frosinone Flysch. Onshore and offshore seismic data, calibrated with lithostratigraphic correlation, have displayed the seismo-stratigraphic framework, including both sedimentary and volcanic seismo-stratigraphic units. Of these, the lavas associated with the Northern Campania Volcanic Zone’s Villa Literno volcano are associated with seismic unit 2a. Seismo-stratigraphic data has shown the offshore prolongation of the Massico structure, as involved by normal faults and flower structures. The whole-data interpretation suggests that the tectonic activity acted in correspondence to normal faults, which have controlled half-graben and interposed structural highs, fitting to the regional geological setting of the continental margin.

José Matildo Paredes, Nicolás Foix, José O. Allard et al.

The Chubut Group (Cretaceous, Golfo San Jorge Basin) is a continental succession up to 6,000 meters thick, preserved in an endorheic basin. Its basal depositional system includes the fluvial Matasiete Formation and the lacustrine Pozo D-129 Formation, the main source rock for the hydrocarbons of the basin. The Matasiete Formation (Aptian) represents a high-accommodation, exotic fluvial system with headwaters in the present-day Cañadón Asfalto Basin (CAB), referred to as the Los Adobes Formation. Sediment was transported southward to a saline-alkaline lake (Pozo D-129 Formation) through N–S sedimentary corridors in an extensional setting. The overlying depositional system is integrated by the Castillo and Mina del Carmen formations (Albian), and it consists of reworked volcaniclastic particles in drainage catchments within a W–E elongated extensional basin, disconnected from the CAB. The subsequent depositional system includes the Bajo Barreal Formation (Cenomanian–Turonian?), containing the main hydrocarbon reservoirs. It shows varied stacking density in hundreds of meters thick cycles, linked to climatic cycles. Low net-to-gross fluvial stratigraphy featuring small-scale channel belts and paleosols indicates a temperate, subhumid/humid climate with seasonal rainfall. High net-to-gross fluvial stratigraphy records larger-scale channel belts interbedded with paleosols developed in a warmer, humid climate with perennial rainfall. The uppermost depositional system includes the paleosol-rich Laguna Palacios Formation at basin margins, with maximum thicknesses along syncline axes, and the red-colored, anastomosing fluvial systems of the Maastrichtian Colhué Huapi Formation that fill incised valleys. Both units are equivalent to the upper strata of Meseta Espinosa and El Trébol formations in the subsurface, showing degradational features marking the onset of surface uplift in the San Bernardo Fold Belt.

Korolev, Yury P., Korolev, Pavel Yu.

The aim of the study was to confirm the possibility of forecasting tsunamis of non-seismic (volcanic) origin using the express method of operational forecasting. The surface wave formed as a result of the explosive volcanic eruption on January 15, 2022 was a superposition of forced (baric) waves caused by an atmospheric pressure wave and free (gravity) waves generated by the disintergration of the disturbance in the source. The express method of operational tsunami forecasting was used to compute the gravitational component of the surface wave. The method allows one to compute the tsunami waveform at any point in the ocean and near the coast in real time based on the data from the sea level measurement stations. The computation of the tsunami on 15.01.2022, its gravitational component, at the DART stations remote from the source was performed based on the data from the DART stations 51425 and 52406 closest to the volcano. For an adequate forecast, the information on the tsunami of the DART stations closest to the source with the duration of a quarter of the first period is sufficient, which is especially important in the operational mode. The result satisfies the definition of the concept of "tsunami forecast" formulated by the Intergovernmental Oceanographic Commission of UNESCO. It has been confirmed that the express method can provide a tsunami forecast regardless of the mechanism of its excitation. It remains unclear how adequate the assessment of the amplitude of surface waves is based on the bottom pressure data is.

Janos Moga, Katalin Fehér, Daniela Strat

In this paper, we present the results of the geomorphological study of the micro pseudokarst landfoms developed on Pâclele Mari mud volcanic site that belongs to the famous mud volcanic area Berca-Arbănași, Buzău Subcarpathians, Romania. Different types of pseudokarstic cavity formation can be observed in the area, especially in the sloping periphery of the mud volcanic area, where badlands developed (badland pseudokarst), and rheogene pseudokarst in the mud flows. The liquid mud material gets denser and wimple on the surface of the mud that flows in the trough, it compiles and then covers the liquid mud channel. These micro-size covered tunnels are similarly formed as lava tubes at the lava flows of real volcanic areas. In order to complement the field measurements, we carried out surveys with a DJI Phantom 3 and 4, and Mavic Pro quadcopter to determine the landforms for the photogrammetry. Granular composition tests were carried out on sediment samples collected in the mud volcanic area by a laser diffraction particle analyser.

Leonid Yakushyn

Formulation of the problem. The relevance of the research is related to the formation of a holistic view of the Late Cretaceous Sea basin of the study area: its boundaries, area, the existence of probable land areas, conditions of sediment accumulation and historical development. The purpose of the article. Based on the results of exploratory, structural-exploratory and parametric drilling conducted during the State Geological Survey on scales of 1:50,000, 1:100,000 and 1:200,000 and own field research, we supplemented the information on the geohistorical chronicle of the Late Cretaceous of the southwestern part of the SEE. Methods. The material for writing the article was the results of drilling more than 10,000 exploration, structural and parametric drilling wells conducted during the State Geological Survey at scales of 1:50,000, 1:100,000 and 1:200,000, which are stored in the State Information Geological Fund of Ukraine. Also, the results of own field research of 47 most complete open sections of the Upper Cretaceous of Platform Ukraine were taken into account and a significant literature on the geological structure of the studied area was processed. Research methods: facies and formation analysis, lithological, petrographic, paleontological, litho-biostratigraphic, geophysical, etc. At the final stage of the mapping of the Upper Cretaceous sediments of Platform Ukraine, the methodology of sedimentary basin monitoring and modeling of formation units was used with the help of the domestic software package "Geomapping" with further conversion to the ArcView grid format. Results. To find out the spatio-temporal distribution of the Upper Cretaceous deposits of the study area, their composition, stratigraphic position and parameters of the Late Cretaceous sea basin, we analyzed the materials of mapping, structural search, exploratory and parametric drilling over the past 50 years were analyzed, our own studies of open sections of the Upper Cretaceous were taken into account, and significant stock material on the geological structure of the studied area was also processed. The most informative wells were selected as reference wells. Their number varied from 1179 for Early-Middle Cenomanian deposits to 1103 for Turonian deposits. The maximum density of the studied sections of support wells was recorded for the territory of Volyn-Podillia and individual blocks of the Ukrainian Shield (USH) and is 23.1 wells per 1000 km2, the minimum - in the water areas of the Ukrainian part of the Black and Azov Seas - about eight per 1000 km2. The absence of Upper Cretaceous deposits on a significant territory of platform Ukraine was established. Early-Middle Cenomanian and Turonian deposits have the largest distribution area, and Maastrichtian deposits have the smallest. In our opinion, areas with continental conditions of existence in certain ages or during the entire Late Cretaceous period have been identified. This made it possible to calculate the areas of land areas and areas covered by the sea with the help of software, with a certain percentage of error (up to 10%). The area of the sea basin was up to 80% of the territory of platform Ukraine. In the historical development of the Late Cretaceous Sea basin of the study area, two stages are distinguished: early-Middle Cenomanian and late Cenomanian-Maastrichtian, which differed significantly from each other in terms of hydrological, hydrochemical, temperature regimes and the nature of sedimentation. The lithological characteristics of the deposits according to the modern stratigraphic division of the Upper Cretaceous rock complex are given.

A. Jourdon, A. Jourdon, D. A. May

<p>Modelling the pressure in the Earth's interior is a common problem in Earth sciences. In this study we propose a method based on the conservation of the momentum of a fluid by using a hydrostatic scenario or a uniformly moving fluid to approximate the pressure. This results in a partial differential equation (PDE) that can be solved using classical numerical methods. In hydrostatic cases, the computed pressure is the lithostatic pressure. In non-hydrostatic cases, we show that this PDE-based approach better approximates the total pressure than the classical 1D depth-integrated approach. To illustrate the performance of this PDE-based formulation we present several hydrostatic and non-hydrostatic 2D models in which we compute the lithostatic pressure or an approximation of the total pressure, respectively. Moreover, we also present a 3D rift model that uses that approximated pressure as a time-dependent boundary condition to simulate far-field normal stresses. This model shows a high degree of non-cylindrical deformation, resulting from the stress boundary condition, that is accommodated by strike-slip shear zones. We compare the result of this numerical model with a traditional rift model employing free-slip boundary conditions to demonstrate the first-order implications of considering “open” boundary conditions in 3D thermo-mechanical rift models.</p>

A. C. Cunningham, J.-P. Buylaert, A. S. Murray

<p>Mineral grains within sediment or rock absorb a radiation dose from the decay of radionuclides in the host matrix. For the beta dose component, the estimated dose rate must be adjusted for the attenuation of beta particles within the mineral grains. Standard calculations, originally designed for thermoluminescence dating of pottery, assume that the grain is embedded in a homogenous medium. However, most current applications of trapped-charge dating concern sand- or silt-sized dosimeters embedded in granular sediment. In such cases, the radionuclide sources are not homogeneous but are localised in discrete grains or held on grain surfaces. We show here that the mean dose rate to dosimeter grains in a granular matrix is dependent on the grain-size distributions of the source grains and of the bulk sediment, in addition to the grain size of the dosimeters. We further argue that U and Th sources are likely to be held primarily on grain surfaces, which causes the dose rate to dosimeter grains to be significantly higher than for sources distributed uniformly throughout grains. For a typical well-sorted medium sand, the beta dose rates derived from surface U and Th sources are higher by <span class="inline-formula">∼</span> 20 % and <span class="inline-formula">∼</span> 30 %, respectively, compared to a homogenous distribution of sources. We account for these effects using an expanded model of beta attenuation – including the effect of moisture – and validate the model against Monte Carlo radiation transport simulations within a geometry of packed spheres.</p>

C. A. Bergemann, C. A. Bergemann, C. A. Bergemann et al.

<p>Zoned hydrothermal monazite-(Ce) from Alpine-type fissures and clefts is used to gain new insights into the tectonic history of the Lepontine Dome in the Central Alps and the timing of deformation along the Rhone-Simplon Fault zone on the dome's western end. Hydrothermal monazites-(Ce) (re)crystallization ages directly date deformation that induces changes in physicochemical conditions of the fissure or cleft fluid. A total of 480 secondary ion mass spectrometry (SIMS) spot analyses from 20 individual crystals, including co-type material of the monazite-(Nd) type locality, record ages for the time of <span class="inline-formula">∼19</span> to 2.7&thinsp;<span class="inline-formula">Ma</span>, with individual grains recording age ranges of 2 to 7.5&thinsp;<span class="inline-formula">Myr</span>. The combination of these age data with geometric considerations and spatial distribution across the Lepontine region gives a more precise young exhumation history for the area. At the northeastern and southwestern edges of the Lepontine Dome, units underwent hydrothermal monazite-(Ce) growth at 19–12.5 and 16.5–10.5&thinsp;<span class="inline-formula">Ma</span>, respectively, while crystallization of monazite-(Ce) in the eastern Lepontine Dome started later, at 15–10&thinsp;<span class="inline-formula">Ma</span>. Fissure monazite-(Ce) along the western limit of the dome reports younger ages of 13–7&thinsp;<span class="inline-formula">Ma</span>. A younger age group around 8–5&thinsp;<span class="inline-formula">Ma</span> is limited to fissures and clefts associated with the Simplon normal fault and related strike-slip faults such as the Rhone Fault. The data set shows that the monazite-(Ce) age record directly links the fluid-induced interaction between fissure mineral and host rock to the Lepontine Dome's evolution in space and time. A comparison between hydrothermal monazite-(Ce) and thermochronometric data suggest that hydrothermal monazite-(Ce) dating may allow us to identify areas of slow exhumation or cooling rates during ongoing tectonic activity.</p>

K. K. Śliwińska, M. J. Head

<p>Species of the fusiform peridiniacean dinoflagellate cyst genera <i>Svalbardella</i> Manum, 1960, emend. (Eocene–Oligocene) and <i>Palaeocystodinium</i> Alberti, 1961 (Late Cretaceous–Miocene), have been examined from the high to middle latitudes of the Northern Hemisphere: Spitsbergen, Norwegian-Greenland Sea, Labrador Sea, western North Atlantic, and the North Sea basin. The genus <i>Svalbardella</i> is emended to comprise species with smooth or finely ornamented surfaces and for which one or both horns are bluntly rounded. <i>Svalbardella clausii</i> sp. nov. has a narrow range restricted to the lowermost Chattian (close to the NP24–NP25 boundary and within Chron C9n), and it therefore appears a useful stratigraphical marker. This species has a wide distribution across the North Atlantic, having been reported from the North Sea basin, western North Atlantic, and the Labrador Sea. <i>Svalbardella clausii</i> sp. nov. overlaps stratigraphically with the reoccurrence interval of <i>Svalbardella cooksoniae</i> Manum, 1960, and spans the Oi-2b cooling maximum. Its presence may therefore be related to the establishment of cooler surface waters at this time.<i> Svalbardella kareniae</i> sp. nov. has a discordant occurrence: Lower Oligocene and Lower Miocene of the Norwegian Sea at Deep Sea Drilling Project Site 338 and Ocean Drilling Program Site 643, respectively, and mid-Oligocene of the North Sea. Its distribution suggests that <i>Svalbardella kareniae</i> sp. nov. favours more open marine conditions. <i>Palaeocystodinium obesum</i> Fensome et al., 2009, described from offshore eastern Canada where it has a highest occurrence in the Lower Oligocene, is emended to include specimens with a finely ornamented periphragm and traces of tabulation in addition to the archeopyle.</p>

F. SÀBAT, B. Gelabert, A. Rodriguez-Perea

Despite forming part of the Balearic group of islands, Minorca differs stratigraphically and structurally from Majorca and Ibiza: i) Paleozoic rocks are abundant in Minorca but are very scarce in Majorca and are absent in Ibiza. Eocene-Oligocene sediments are virtually absent in Minorca but crop out extensively in Majorca, ii) Contractional structures in Minorca differ in direction (aligned SW-NE in Majorca and Ibiza and N-S in Minorca) and in age from those in Majorca and Ibiza. In addition, Paleozoic deposits of Minorca do not correlate with those of Sardinia, where in addition the Triassic sediments are not very abundant. Contractional deformation in Sardinia is in part older (late Eocene-early Miocene) than in Minorca (early Miocene?). Given its Neogene clockwise rotation, Minorca cannot be considered a small block dragged by the early Miocene counter clockwise rotation of the Corsica-Sardinia block. Furthermore, the Paleozoic and Mesozoic stratigraphy of Minorca (siliciclasticlate Paleozoic rocks, Triassic Germanic facies and Jurassic carbonates) has affinities with that of the southern part of the Catalan Coastal Ranges. Thus, of all the Balearic islands, Minorca seems to have traveled the farthest during the Valencia Trough rifting with the result that it resembles an exotic island forming part of the Balearic foreland.

Gregor Kovačič

Kraški izviri predstavljajo pomemben vir pitne vode tako v Sloveniji kot v svetu. Zaradi specifične zgradbe so kraški vodonosniki v večini zelo občutljivi na onesnaženje. Avtor na primeru kraškega izvira Bistrica izpostavi problematiko varovanja kraške podtalnice ter predstavi glavne pomanjkljivosti ter slabosti sedanje zakonodaje in uveljavljene prakse na področju varovanja kraških vodonosnikov v Sloveniji. Kljub relativno ugodnim razmeram za varovanje (redka poseljenost, manj intenzivno kmetijstvo,…) v primerjavi s kraškimi območji drugod po svetu je veliko pomembnih kraških izvirov slabo zavarovanih. Vodovarstveni režimi so največkrat slabo definirani, nadzor nad izvajanjem zaščitnih ukrepov pa neučinkovit. Karst springs are important drinking water sources both in Slovenia and elsewhere in the world. Due to their specific structure, karst aquifers are in most cases highly vulnerable to pollution. Through the example of the Bistrica karst spring, the author highlights the problems of karst groundwater protection and presents the main shortcomings and weaknesses of the relevant legislation in force and of established practices in the field of the protection of karst aquifers in Slovenia. Despite relatively favourable conditions for water protection (scarce population, less intensive agricultural activities etc.) as compared with karst areas elsewhere in the world, many important karst springs in Slovenia are improperly protected. Water protection regimes are often established inappropriately and control over the implementation of protective measures is inefficient.

Mohammadreza Ghotbi, Mehdireza Poursoltani

The siliciclastic Dahu Strata (Early Cambrian), in the Central Iran, 280 metres thick, in the Gazouieyeh area, rests with an erosional surface on Protrozoic-Early Cambrian sedimentary rocks (Dezu Series). This strata disconformably overlain by Middle Cambrian-Late Cambrian marine carbonate rockse (Kouh-Banan Formation). Based on field and Laboratory studies, 3 association facies, shale-sandstone and conglomerate have been identified. Mainly, sandstones are rich in quartz, feldspars, and rarely contain rock fragments (metamorphic and sedimentary). The sandstones have a wide compositional range from quartzarenite to arkose, feldspathic litharenite and rarely litharenite (chertarenite). According to plots of feldspar garins, total quartzose grains, and total unstable lithic fragments, they were derived from craton interior, transitional continental, and recycled orogen sources. The Dahu sandstones experienced diagenetic events that included compaction and pressure solution, cementation (mostly by silica, carbonate, Fe-oxide, clay and rarely by barite), grain fracturing, alteration of unstable grains, dissolution and replacement. Based on petrological and geochemical studies, we interpreted the diagenetic history for the Dahu sandstones, which consists of early, deep burial and late stages. The above results are based on surface studies, but it might be changed during increasing the depth.

Gaudenji Tivadar, Jovanović Mlađen

Corrections to the Quaternary stratigraphic division of Serbia was updated/renewed by lowering limit of the Pleistocene / Quaternary to the beginning of the Gelasian that is at approximately 2.588 million years. Rather than the officially rejected Penck & Brückner Alpine stratigraphic model, the use of oxygen isotope stages (OIS / MIS) is recommended. Climatostratigraphic terms glacial and interglacial have a regional applicability and their use is recommended only in areas where there are traces of glaciation, while the terms cold and warm stage (or moderate) stages should be used within the global context. Eopleistocene is a regional term for the former Soviet Union and due to its uniqueness it can hardly be applied in the stratigraphical scheme of the Quaternary depostis in Serbia. With the latest extension of the Lower Pleistocene, further use of Eopleistocene would lead to further confusion in stratigraphic correlation as such the use of the Lower / Early Pleistocene or other appropriate stratigraphic units is recommended. [Projekat Ministarstva nauke Republike Srbije, br. 47007]

Dubravko Matičec, Igor Vlahović, Ladislav Fuček et al.

<div>Twelve lithostratigraphic units, representing a 5 km thick succession,</div><div>have been determined from the Senj -Ogulin profile through the</div><div>Velika Kapela Mt. This 45 km long sequence lies approximately normal</div><div>to the Dinaric strike. Carbonate deposits ranging from the Middle</div><div>Liassic to the Albian include laterally variable environments during</div><div>the Kimmeridgian and Lower Tithonian. The deposits were deformed</div><div>by compressive tectonics during the Tertiary tectonic cycle, and were</div><div>consequently reshaped by weaker Neotectonic transpression. Therefore</div><div>structures with the N-S strike, which are different to the common</div><div>Dinaric strike (NW-SE), are interpreted as a consequence of syngenetic bending during the Tertiary cycle, rather than rotation during the</div><div>Neotectonic cycle.</div>

Stephan Kempe, Doris Döppes

The Linnean binomial system rests on the description of a holotype. The first fossil vertebrate species named accordingly was Ursus spelaeus, the cave bear. It was described by Rosenmüller in 1794 in his dissertation using a skull from the Zoolithen Cave (Gailenreuth Cave) in Frankonia, Germany. The whereabouts of this skull is unknown. In the Humboldt Museum, Berlin, historic skulls of the three “spelaeus species” (cave bear, cave lion, cave hyena) are displayed. We were allowed to investigate them and further material in the Museum’s archive in an attempt to locate the holotype skull. Here we report about our findings giving pertinent measurements of this historic material and depicting it for the first time. Studying the old labels we were able to establish the provenience of much of the material that includes in fact specimens from the original Rosenmüller collection. One of the cave lion skulls may actually be the one used in establishing the cave lion by Goldfuß (Diedrich 2008) while another may be the original that was used to define a “cave wolf ”.

Ivo Velić

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:595.3pt 841.9pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --><p class="MsoNormal">The Adriatic Carbonate Platform (AdCP), was a separate shallowmarine depositional system characterized by a lack of terrigenous input and was connected to Gondwana towards the South via Gavrovo–Tripolitza or Apulia. It existed for approximately 120 MY, from the Early Jurassic Pliensbachian/Toarcian) to the end of the Cretaceous, resulting in a 4000–6500 m thick succession of almost pure carbonates. However, this is part of a thicker (>8000 m) sequence of predominantly carbonate rocks which forms the Karst Dinarides, and was deposited during more than 270 MY – at least from the Carboniferous (Moscovian) to the Late Eocene. </p><p style="text-indent: 35.4pt" class="MsoNormal">Among many different groups of fossil organisms, benthic foraminifera are especially abundant and well preserved, so they, along with calcareous algae (Dasycladales), are the most important fossils used for age determination and stratigraphic subdivision of<br />shallow-marine carbonate deposits. </p><p style="text-indent: 35.4pt" class="MsoNormal">Within the 257 determined taxa belonging to different foraminiferal families which lived through the Mesozoic, numerous different index fossils occur in assemblages indicating various ages: Early Triassic, Anisian, Carnian, Norian–Rhaetian, Late Sinemurian, Early and Late Pliensbachian (Carixian and Domerian), Early and Late Aalenian, Early and Late Bajocian, Early and Late Bathonian, Callovian, Early and Late Oxfordian, Kimmeridgian, Tithonian, Berriasian, Valanginian, Late Hauterivian, Late Barremian, Early and Late Aptian (Bedulian and Gargasian), Early and Late Albian, Early, Middle and Late Cenomanian, Turonian, Coniacian, Santonian, Early and Late Campanian and Early and Late Maastrichtian.</p><p style="text-indent: 35.4pt" class="MsoNormal">A total of 64 biostratigraphic units – biozones of different categories, from subzone to superzone, were defined within the stratigraphic interval from the Carnian to the Late Maastrichtian. This enabled very detailed biostratigraphic subdivision of the carbonate deposits within the Karst Dinarides. This is one of the most precise sequences, not only in this area, but also among former shallow marine deposits of the entire Neotethyan realm in the present Mediterranean region. </p><p style="text-indent: 35.4pt" class="MsoNormal">The palaeobiogeographic characteristics of biotopes and the composition of foraminiferal assemblages during the Mesozoic were controlled by the position of the study area within the Neotethyan bioprovinces. Until the Albian, this area represented part of the Southern Neotethyan bioprovince, while from the Cenomanian to its final disintegration at the end of the Cretaceous it belonged to a separate, Central<br />Mediterranean Neotethyan bioprovince.</p>

Luiz Eduardo Panisset Tavassos, Edson Gomez Travassos, Lucília Panisset Tavassos et al.

The aim of this work is to recover some methodological aspects of the study about the mind representations of caves in Brazil. The basis of this research consisted of one essay, approaching the social representations of a particular group of high school students on the exokarst and the endokarst. The results showed that the meanings vary only slightly, however, the most interesting result was due to the fact that students, who had already visited caves in some period of their lives, still held “negative” concepts regarding this environment even before visual stimulations. About 640 words associated with the exokarst and the endokarst were mentioned, emphasizing: fear, dark, shadowy, skull, hidden places, fantastic and beauty, which helped identifying relations between the cultural and psychological aspects of the group, mainly general views about the obscure and mysterious aspects of this landscape and its prominence over natural beauties. Analyzed data showed that the development of new research on mind representations of caves is very important, mainly for environmental education programs promoting adequate concepts about caves and extending activities of educational ecotourism in Brazilian caves.

Andsbjerg, Jan

The Middle Jurassic Bryne and Lulu Formations of the Søgne Basin (northern part of the Danish Central Graben) consist of fluvially-dominated coastal plain deposits, overlain by interfingering shoreface and back-barrier deposits. Laterally continuous, mainly fining-upwards fluvial channel sandstones that locally show evidence for tidal influence dominate the alluvial/coastal plain deposits of the lower Bryne Formation. The sandstones are separated by units of fine-grained floodplain sediments that show a fining-upwards - coarsening-upwards pattern and locally grade into lacustrine mudstones. A regional unconformity that separates the lower Bryne Formation from the mainly estuarine upper Bryne Formation is defined by the strongly erosional base of a succession of stacked channel sandstones, interpreted as the fill of a system of incised valleys. Most of the stacked channel sandstones show abundant mud laminae and flasers, and rare herringbone structures, suggesting that they were deposited in a tidal environment, probably an estuary. Several tens of metres of the lower Bryne Formation may have been removed by erosion at this unconformity. The estuarine channel sandstone succession is capped by coal beds that attain a thickness of several metres in the western part of the Søgne Basin, but are thin and poorly developed in the central part of the basin. Above the coal beds, the Lulu Formation is dominated by various types of tidally influenced paralic deposits in the western part of the basin and by coarsening-upwards shoreface and beach deposits in central parts. Westwards-thickening wedges of paralic deposits interfinger with eastwards-thickening wedges of shallow marine deposits. The Middle Jurassic succession is subdivided into nine sequences. In the lower Bryne Formation, sequence boundaries are situated at the base of laterally continuous fluvial channel sandstones whereas maximum flooding surfaces are placed in laterally extensive floodplain or lacustrine mudstones. The unconformity that separates the alluvial plain deposits of the lower Bryne Formation from the estuary deposits of the upper Bryne Formation is interpreted as a sequence boundary that bounds a system of incised valleys in the western and southern parts of the basin. Sequence boundaries in the Lulu Formation are situated at the top of progradational shoreface units or at the base of estuarine channels. Maximum flooding surfaces are located within marine or lagoonal mudstone units. Marine highstand deposits are partitioned seawards, in the eastern part of the basin, whereas paralic transgressive deposits are partitioned landwards, in the west. This marked sediment artitioning in the uppermost part of the succession resulted from the alternation of episodes of fault-induced half-graben subsidence with periods of slow uniform subsidence.