Late Triassic dinosaur tracks from Penarth, south Wales

Evidence of Late Triassic large tetrapods from the UK is rare. Here, we describe a track-bearing surface located on the shoreline near Penarth, south Wales, United Kingdom. The total exposed surface is c. 50 m long and c. 2 m wide, and is split into northern and southern sections by a small fault. We interpret these impressions as tracks, rather than abiogenic sedimentary structures, because of the possession of marked displacement rims and their relationship to each other with regularly spaced impressions forming putative trackways. The impressions are large (up to c. 50 cm in length), but poorly preserved, and retain little information about track-maker anatomy. We discuss alternative, plausible, abiotic mechanisms that might have been responsible for the formation of these features, but reject them in favour of these impressions being tetrapod tracks. We propose that the site is an additional occurrence of the ichnotaxon Eosauropus, representing a sauropodomorph trackmaker, thereby adding a useful new datum to their sparse Late Triassic record in the UK. We also used historical photogrammetry to digitally map the extent of site erosion during 2009–2020. More than 1 m of the surface exposure has been lost over this 11-year period, and the few tracks present in both models show significant smoothing, breakage and loss of detail. These tracks are an important datapoint for Late Triassic palaeontology in the UK, even if they cannot be confidently assigned to a specific trackmaker. The documented loss of the bedding surface highlights the transient and vulnerable nature of our fossil resources, particularly in coastal settings, and the need to gather data as quickly and effectively as possible.

Borehole wall tensile caving instability in the horizontal well of deep brittle shale

Introduction: With the increasing drilling depth of shale formation, downhole collapse is a frequent occurrence, which often manifests as borehole wall caving. Methods: We used the deep shale of the Longmaxi Formation to conduct the mechanical loading and unloading experiments under different downhole working conditions and a theoretical evaluation method of borehole wall caving and instability was proposed. Results and discussion: As the confining pressure and axial load increased, the acoustic velocity increased. When a certain value was reached, the acoustic velocity of the rock mass had minimal changes. As the confining pressure continued to unload and decrease, the acoustic velocity decreased. At the moment of core failure, the acoustic velocity suddenly dropped. When the axial force of loading was constant, the unloading speed of confining pressure increased, and shale could easily be destroyed. The pressure at the well bottom changed rapidly, the likelihood of borehole wall failure increased. Conclusion: The deep shale has high brittleness. Under the bottom-hole pressure, the borehole wall rock was prone to brittle fracture failure along the parallel bedding surface. Under different working conditions, obvious changes could be observed in the pressure of the effective fluid column at the well bottom. The pressure changed rapidly, which, in turn, caused the rock at the well bottom to break down, thereby resulting in borehole wall caving. After tripping out and turning the pump off, the shale tensile stress in the upper and lower sidewalls of the horizontal well section was responsible for tensile caving.

An improved high-precision Jacob's staff with laser sighting and topographic capabilities for the high-resolution stratigrapher

ABSTRACT Accurate and quick high-resolution measurements of stratigraphic thicknesses and geologic profiles exposed in surface outcrops are critically important for interpreting depositional environments, basin development, and tectonic evolution. Therefore, a high-precision instrument is required for high-resolution stratigraphic measurements. Herein, a new version of the Jacob's staff incorporating an Abney level or a geological compass, a laser pointer, and a handheld GPS is presented. Both the Abney level and the laser pointer are oppositely positioned side by side at the 1.5 m position on the 1.6-m-long fiberglass rod, and they can synchronously slide vertically and rotate horizontally. Because accurate sighting of bedding surfaces is facilitated with both the sighting tube of the Abney level and straight-line beam of the laser pointer, this novel design greatly improves the precision and speed of stratigraphic thickness measurements. More importantly, when the section requires a lateral shift, the straight-line beam can easily and precisely identify the new start point without rotating the rod, which greatly reduces potential changes in the angle of the rod. The GPS unit installed at the top of the rod synchronously records the track of the measured section and coordinates of each measurement, which enables acquisition of a topographic profile along the stratigraphic section. Uncertainties in stratigraphic thickness measurements are minimized when observations are made through the sight tube of the Abney level when the rod is oriented perpendicular to the bedding surface.

Features of lead-zinc mineralization in the Phia Dam - Khuoi Man region

The paper introduces a number of new research results on the characteristics of lead - zinc ores in Phia Dam - Khuoi Man areas based on the application of traditional geological methods, combining the method of researching material composition and method statistical maths. In the study area, there are two forms of ore bodies with characteristics described as below: the first form consists of ore bodies developed along the stratabound bedding surface, are mainly distributed in either anticlinal structures (i.e. Phia Dam region) or cuesta (i.e. Khuoi Man region) and the second form consists of ore bodies in lodes, filled in cracks or zones of fracture along the northwest – southeast faults. Primary ore minerals are mainly galena, sphalerite, pyrite, chalcopyrite, etc. and gangue minerals are calcite, dolomite, and quartz. Ore structures are nests, veins, disseminated veins, banded, speckled, or sometimes breccia - like ones. The relevant and controlling factors of lead-zinc mineralization in Phia Dam - Khuoi Man region are the northwest - southeast fault system and the lithostratigraphy. Ores are of either mesothermal or epithermal deposits (temperatures varies from 162 to 308 degrees Celcius), with a specific symbiotic combination of quartz - sphalerite - galena - chancopyrite.

Verification of Thermo-Technical Characteristics of Selected Floor Constructions for Dairy Cows (Pilot Study)

The purpose of this study was to theoretically and practically investigate the thermo-technical properties of two bedding surface materials under real farm conditions during the hot summer period. The study was focused on the research of cubicles with water mattresses and straw bedding for dairy cows. The results of thermal-technical calculations showed that straw belongs to the category of warm floors, the thermal effusivity value of cubicle with straw is b = 173.55 W·s1/2·m−2·K−1; the heat transfer coefficient is U = 0.36 W·m−2·K−1. Water mattress belongs to the category of cold floors with the thermal effusivity value b = 572.46 W·s1/2·m−2·K−1 and the heat transfer coefficient U = 4.504 W·m−2·K−1. On the basis of calculations, the results showed that U was 12.5 higher for water mattresses than for straw, and b was 3.3 times higher for water mattresses than for straw. Based on thermographic measurements under field conditions of dairy farm, it was observed that the surface temperature of the water mattresses after one hour of lying was lower by 4.95 ±1.88 °C in comparison to chopped straw. In practice, suitability of the material structure of water mattresses was verified on the basis of physical properties for summer period.

The putative Ordovician annelid worm Haileyia adhaerens Ruedemann, 1934 is not a recognizable fossil

A number of putative annelid worms have been described from Ordovician strata, and these records are included in large-scale compilations of paleontological data. If these fossils are worms, they may yield important phylogenetic information; conversely, if they are not worms, they should not be included in large-scale databases. In either case, restudy of the type material of these supposed annelids is useful. The type material (holotype and one paratype) of one of these putative annelids, Haileyia adhaerens Ruedemann, 1934, from the Middle Ordovician Normanskill Shale of Idaho, USA, is re-described and re-illustrated. The original description stated that the species is segmented, with parapodia, papillae, and setae, and lived attached to graptolites. Upon re-examination, the setae could not be detected, and the segmentation, parapodia, and papillae are herein re-interpreted as taphonomic, rather than biological, features. The supposed attachment of Haileyia to graptolites is likely to represent fortuitous bedding-surface associations. There is no evidence that Haileyia adhaerens is an annelid, or even a recognizable fossil.

Experimental Analysis of Condensation Rate in Conductive Cooling Systems for Dairy Cattle

Conductive cooling for dairy cattle is an emerging technology that holds promise as a way of relieving heat stress. A conductive cooling system using modified Dual Chamber Comfort (DCC) waterbeds from Advanced Comfort Technologies as heat exchangers placed in the stalls of dairy cows was tested. Rate of moisture accumulation in two types of bedding (sand and sawdust) was studied for two levels of relative humidity (RH) of air (~60% and ~75%). Four bedding thicknesses were considered in this study and were 0.5, 2.5, 7.5, and 20 cm. The experiment consisted of the following: (1) two waterbeds cooled by circulating water at 4.5°C, and (2) two more waterbeds (control) where the water in the waterbeds was not cooled. Moisture content of the bedding was measured in duplicate at three locations on the surface of each waterbed for each of 20 treatments (sand and sawdust bedding measured at both ~60% RH and ~75% RH and at five bedding thicknesses/sampling depths). The moisture measurements were conducted before and after 2 h of cooling. In cases where the bedding thickness was 2.5 cm or more, the temperature of the bedding was measured at three points using thermocouples: (1) at the surface of the waterbed, (2) at mid depth, and (3) at 0.5 cm below the bedding surface. Mixed linear models were used to calculate the condensation rates and the equilibrium temperatures. In all treatment combinations, the surface temperature of the cooled waterbeds was at least 7.5°C lower than the dewpoint temperature of the air. For the 0.5-cm thick sawdust, condensation rates, calculated in percent increase in dry basis of moisture content per hour (% d.b. h-1), were 3.5% d.b. h-1 higher for the cooled waterbeds than that for the control waterbeds at the ~75% RH. For 0.5-cm thick sawdust at ~60% RH, the condensation rate for the cooled waterbeds was 3.1% d.b. h-1 higher than that for the control waterbeds. Similarly, the condensation rates for the 0.5-cm thick sand were 2.0% d.b. h-1 higher for the cooled waterbeds than for the control waterbeds at the ~75% RH conditions and 1.3% d.b. h-1 higher at the ~60% RH conditions. The condensation rate for the 2.5-cm thick sand bedding measured at the top surface of the waterbed (the bottom 0.5 cm of the bedding) was statistically significant but negligible (0.1% d.b. h-1). No other treatments yielded any difference in condensation rate between the cooled waterbeds and the control waterbeds. Keywords: Animal housing, Bedding thickness, Condensation rate, Conductive cooling, Dairy cows, Stall bedding.

Morphology, systematics, and paleoecology of Tridactylastacus (Crustacea, Decapoda, Glypheidea, Litogastridae)

A large assemblage of small specimens of Tridactylastacus sinensis Feldmann, Schweitzer, and Zhang in Feldmann et al., 2012, from the Middle Triassic (Anisian) Luoping Biota, Yunnan Province, China, permitted cladistic analysis confirming their placement within Litogastridae in the superfamily Glypheoidea. Orientation of 86 specimens closely spaced on a single slab from one bedding surface revealed a preferred orientation suggestive of mild current activity. The specimens were interpreted to have been victims of a mass kill, possibly an algal bloom, within the water column.

Sedimentology and ichnology of the Mafube dinosaur track site (Lower Jurassic, eastern Free State, South Africa): a report on footprint preservation and palaeoenvironment

Footprint morphology (e.g., outline shape, depth of impression) is one of the key diagnostic features used in the interpretation of ancient vertebrate tracks. Over 80 tridactyl tracks, confined to the same bedding surface in the Lower Jurassic Elliot Formation at Mafube (eastern Free State, South Africa), show large shape variability over the length of the study site. These morphological differences are considered here to be mainly due to variations in the substrate rheology as opposed to differences in the trackmaker’s foot anatomy, foot kinematics or recent weathering of the bedding surface. The sedimentary structures (e.g., desiccation cracks, ripple marks) preserved in association with and within some of the Mafube tracks suggest that the imprints were produced essentially contemporaneous and are true dinosaur tracks rather than undertracks or erosional remnants. They are therefore valuable not only for the interpretation of the ancient environment (i.e., seasonally dry river channels) but also for taxonomic assessments as some of them closely resemble the original anatomy of the trackmaker’s foot. The tracks are grouped, based on size, into two morphotypes that can be identified asEubrontes-like andGrallator-like ichnogenera. The Mafube morphotypes are tentatively attributable to large and small tridactyl theropod trackmakers, possibly toDracovenatorandCoelophysisbased on the following criteria: (a) lack of manus impressions indicative of obligate bipeds; (b) long, slender-digits that are asymmetrical and taper; (c) often end in a claw impression or point; and (d) the tracks that are longer than broad. To enable high-resolution preservation, curation and subsequent remote studying of the morphological variations of and the secondary features in the tracks, low viscosity silicone rubber was used to generate casts of the Mafube tracks.

Use of soft hydrothermal processing to improve and recycle bedding for laboratory animals

Cage bedding for laboratory rodents can influence animal wellbeing and thus the experimental data. In addition, a large amount of used bedding containing excrement is discharged as medical waste from life science institutes and breeding companies. We developed a ground-breaking system to improve fresh bedding and recycle used bedding by applying a soft hydrothermal process with high-temperature and high-pressure dry steam. The system removes both harmful organic components and aromatic hydrocarbons that can affect animals’ metabolism. The purpose of the present study was to evaluate the chemical and physical properties of the improved fresh bedding and the recycled used bedding treated by the system. The results showed that 68-99% of the predominant aromatic hydrocarbons were removed from fresh bedding treated at 0.35 MPa and 140°C for 120 min (‘improved bedding’). In addition, 59.4-99.0% of predominant harmful organic compounds derived from excrement were removed from used bedding treated at 0.45 MPa and 150°C for 60 min (‘recycled bedding’). The soft hydrothermal treatment increased the number of acidic functional groups on the bedding surface and gave it the high adsorptive efficiency of ammonia gas. Harmful substances such as microorganisms, heavy metals and pesticides decreased below the detection limit. The results clearly showed that the improved and recycled bedding is safer for laboratory rodents and has the potential to ameliorate conditions in primary and secondary enclosures (e.g. cages and animal rooms) used for maintaining laboratory animals. This process may be one of the most advanced techniques in providing an alternative to softwood and other bedding, economizing through the recycling of used bedding and reducing bedding waste from animal facilities.