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Vibrations of drill strings in oil and gas well bores can reduce drilling performance or lead to damage of drill string components. These vibrations are neither optically observable nor measurable because of the geological formation. Hence usually simulations are used to understand the dynamic behavior. The test stand 'OSTrator' adds more insight to this problem. The demonstrator represents a scaled drill rig granting direct access to the complex dynamic behavior of the real drill string. Two phenomena are of special interest: the stick-slip effect, a torsional oscillation, and the whirl effect, a periodic torsional-lateral movement with permanent wall contact. Since the OSTrator was built for showcase purposes, it has to be piloted in and out Stick-Slip and Whirl domains by a control algorithm. Therefore efficient multi-body-systems able to represent these two effects in faster than real time are demanded. In this presentation, the modeling of the stick-slip and the whirl effect are discussed. The models should be able to predict these effects and supply data to avoid or confront them. Key questions are the modeling of the wall contact and the resistance at the drill bit. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The article presents a case study of the geological control factors and corresponding Estimated Ultimate Recovery (EUR) of tight reservoir of Daanzhai Formation, Jurassic of Central of the Sichuan Basin in China. Particular focus is given to the link between geological elements and their corresponding EUR. It explains EUR as a criteria for oil production capacity as well as explores the porosity and permeability of the reservoir.

An abstract of the article "The Identification Mark and Present Situations of Marine Hydrate" by Li Zhandong and colleagues is presented.

The article offers news briefs related to geographical research and studies. A series of monazite grains collected from the black sands of northern Sinai were examined. David Loope and his colleagues went to the Utah-Arizona border to examine the role of wind in the development of the Jurassic Navajo Sandstone. A view on the Zumaya coastal exposures in the Basque Region of Spain is also presented.

Or, how the‘Dudley Bug’ escapes from a town Museum in the English Midlands and tries to find its way back on to Dudley's Coat of Arms... [ABSTRACT FROM AUTHOR]

Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic. [ABSTRACT FROM AUTHOR]

A single specimen, part and counterpart of a carapace, of a horseshoe crab from the Lower Cretaceous (Albian) Glen Rose Formation in north-central Texas, forms the basis for the definition of a new genus and species, Crenatolimulus paluxyensis. The discovery represents only the fifth limuline known from the Cretaceous. Its preservational style is remarkable in that the carapace exterior is faithfully replicated by a massive overgrowth of serpulid worms. [ABSTRACT FROM AUTHOR]

Proceedings of the 7th Austrian Tunnel Day Particular challenges on current large-scale construction projects / Besondere Herausforderungen aktueller Großbaustellen Thomas Längle & Lukas Käppeli: Visp bypass, Eyholz Tunnel - a road tunnel in difficult geology with crosssections up to 300 m2 / Umfahrung Visp, Tunnel Eyholz - Straßentunnel in schwieriger Geologie mit Querschnitten bis zu 300 m2 Peter Schwab: Tunnel refurbishment - a job with surprises / Tunnelsanierung - Eine Arbeit mit Überraschungen H. G. Jodl & Jörg Ehgartner: Tolerances in tunnelling - small cause and great effect / Toleranzen im Tunnelbau - kleine Ursache mit großer Wirkung Bernd Raderbauer: The autobahn ring Biel Ostast - driving four tunnels in variable geology / Autobahnumfahrung Biel Ostast - Vortrieb von vier Tunneln in wechselnder Geologie Christian Gamper: Tunnelling in Hungary - Construction site tunnel chain M6 / Tunnelbau in Ungarn - Baustelle Tunnelkette M6 Franz Pacher: Bosruck Tunnel second bore - a challenge for sequential tunnelling in various geological formations / Bosrucktunnel zweite Röhre - Herausforderung zyklischer Vortrieb in unterschiedlichen geologischen Formationen NATM - quo vadis? The current status of the NATM in construction contracts / NATM - quo vadis? Gegenwart der NATM im Bauvertrag Harald Lauffer: NATM - basic reference / NÖT - Grundsatzreferat Nejad Ayaydin: NATM - design / NÖT - Planung Johannes Herdina: NATM - tendering / NÖT - Ausschreibung M. Sachs: NATM - construction / NÖT - Ausführung Manfred Bauer: The future of the NATM / Zukunft der NATM [ABSTRACT FROM AUTHOR]

Presents a photograph as a geological puzzle that requires an interpretation of its features and location.

Recounts the existence of a Welsh slate quarry in the ridges of Brendon Hills on the northern slopes of Exmoor, England and describes the local geology then and thereafter. Sandstones, siltstones and slates of the Ilfracombe Beds; Rock cleavage; History of the Welsh enterprise.

Editorial. Presents a discussion on hydrogeological research that focuses on the importance and effect of hydrogeology on the environment. Discussions on how ground water resources and the field of hydrogeology might be impacted by global warming; Disposable methods used in geologic transformations; Major types of formations considered in hydrogeology.

Comments on photograph of Culver Cliff taken by the author in August 1999. Strata revealed by the offshore photograph.

Upper Ordovician (Caradocian) carbonates of eastern North America were deposited along the Iapetus continental margin and record a transition from warm- to cool-water settings despite this margin having been within the southern hemisphere tropical belt. This event has been documented from Virginia (USA) to southern Québec (Canada) although, not previously from areas close to the palaeoequator. Field, petrographic and major element geochemistry data have been gathered from the poorly-known Upper Ordovician carbonate succession outcropping in the Lac Saint-Jean outlier in central Québec. The succession consists of a lower siliciclastic formation (Tremblay) overlain by three limestone formations (Simard, Shipshaw and Galets) and capped by shales (Pointe-Bleue Shale). From macro- and microfaunal evidence, carbonate sedimentation occurred during the late Caradoc and is younger than the early- to mid-Caradoc carbonate succession present farther south. Relative sea level fluctuations recorded in the sediments suggest an overall sea level rise briefly halted by a minor end-Caradocian sea level fall. The lower limestone formation (Simard) consists of muddy sediments with algal-coral-stromatoporoid boundstones; green algae are abundant. This unit reflects low energy sedimentation on a shallow warm-water carbonate ramp colonized by a diverse chlorozoan fauna. The upper limestone formation (Galets) is typified by coarse-grained bioclastic sediments punctuated by numerous phosphate-rich hardgrounds with evidence for high energy shallow marine conditions. Faunas were dominated by crinoids and bryozoans. This unit represents high energy sedimentation on a cool shallow water carbonate ramp colonized by a brynoderm faunal association. Between both units, a deeper marine (outer shelf) limestone formation (Shipshaw) was developed. In the Lac Saint-Jean area, a transition from warm- to cool-water carbonate ramps occurred in latest Caradoc times and is litho- and bio... [ABSTRACT FROM AUTHOR]

Two calcite cements, filling karst cavities and replacing Lower Carboniferous limestones at the Variscan Front Thrust, were precipitated after mid-Jurassic Cimmerian uplift and subsequent erosion but before late Cretaceous strike-slip movement. The first calcite (stage A) is nonferroan and crystals are coated by hematite and/or goethite. These minerals also occur as inclusions along growth zones. The calcite lattice contains < 0·07 mol.% Fe, but Mn concentrations can be as high as 0·72 mol.% in bright yellow luminescent zones. Primary, originally one-phase, all-liquid, aqueous inclusions have a final melting temperature between -0·2° and +0·2 °C, indicating a meteoric origin of the ambient water. The δ[sup 13]C and δ[sup 18]O values of the calcites are between -7·3‰ and -6·3‰, -7·8‰ and -5·5‰ on the Vienna PeeDee Belemnite (VPDB) scale, respectively. The second calcite (stage B) consists of ferroan (0·13–0·84 mol.% Fe) blocky crystals with Mn concentrations between 0·34 and 0·87 mol.%. Primary, single-phase aqueous fluid inclusions indicate precipitation from a meteoric fluid below 50 °C . The δ[sup 13]C values of stage B calcites vary between -7·3‰ and -2·1‰ VPDB and the δ[sup 18]O values between -7·9‰ and -7·2‰ VPDB. A precipitation temperature below 50 °C for the stage A calcites and the presence of iron oxide/hydroxide inclusions in the crystals indicate near-surface precipitation conditions. Within this setting, the geochemistry of the nonferroan stage A calcites reflects precipitation under oxic to suboxic conditions. The ferroan stage B calcites precipitated in a reducing environment. The evolution from the stage A to stage B calcites and the associated geochemical changes are interpreted to be related to the change from semiarid to humid conditions in western Europe du... [ABSTRACT FROM AUTHOR]

Analyzes the structure of the Bude Formation in south-west England. Composition and features of the Bude Formation; Occurrence of deposition in a Westphalian lake with occasional connections; Growth of a series of subsea fan turbidite-systems across the basin floor on the northern, passive margin of a foreland basin.