Chitinozoans recovered from cores BG-14 and WS-6 in southern and eastern Jordan are described. Sample ages are well-constrained by graptolite data to the ascensus-acuminatus and vesiculosus graptolite biozones. Eighteen chitinozoan taxa are recognized, with Spinachitina fragilis, Plectochitina nodifera, Ancyrochitina laevaensis and Belonechitina postrobusta allowing correlation with both local and global chitinozoan and graptolite biozonations for the Rhuddanian. One new species of chitinozoan is erected, Belonechitina pseudarabiensis sp. nov.

Hydraulic fracturing (HF) at Preston New Road (PNR), Lancashire, United Kingdom, in August 2019, induced a number of felt earthquakes. The largest event (ML 2.9) occurred on 26 August 2019, approximately three days after HF operations at the site had stopped. Following this, in November 2019, the United Kingdom Government announced a moratorium on HF for shale gas in England. Here we provide an analysis of the microseismic observations made during this case of HF-induced fault activation. More than 55,000 microseismic events were detected during operations using a downhole array, the vast majority measuring less than Mw 0. Event locations revealed the growth of hydraulic fractures and their interaction with several preexisting structures. The spatiotemporal distribution of events suggests that a hydraulic pathway was created between the injection points and a nearby northwest–southeast-striking fault, on which the largest events occurred. The aftershocks of the ML 2.9 event clearly delineate the rupture plane, with their spatial distribution forming a halo of activity around the mainshock rupture area. Across clusters of events, the magnitude distributions are distinctly bimodal, with a lower Gutenberg–Richter b-value for events above Mw 0, suggesting a break in scaling between events associated with hydraulic fracture propagation, and events associated with activation of the fault. This poses a challenge for mitigation strategies that rely on extrapolating microseismicity observed during injection to forecast future behavior. The activated fault was well oriented for failure in the regional stress field, significantly more so than the fault activated during previous operations at PNR in 2018. The differing orientations within the stress field likely explain why this PNR-2 fault produced larger events compared with the 2018 sequence, despite receiving a smaller volume of injected fluid. This indicates that fault orientation and in situ stress conditions play a key role in controlling the severity of seismicity induced by HF.

9Local seismic magnitudes provide a practical scale for quick implementation of regulation 10 designed to manage the risk of induced seismicity, such as Traffic Light Schemes. We 11 demonstrate that significant magnitude discrepancies occur when seismic events are recorded 12 on nearby stations (<5km), which can be a unit higher values than those observed on more 13 distant stations. This is due to the influence of sedimentary layers, as these shallow layers are 14 generally lower in velocity and more attenuating than the underlying crystalline basement rocks, 15and require a change in the attenuation term of the M L scale. This has a significant impact on the 16 UK's hydraulic fracturing Traffic Light Scheme whose 'red' light is set at M L = 0.5. As the nominal 17 detectability of the UK network is M L = 2, this scheme will entail the deployment of monitoring 18 stations in close proximity to well sites. Using data collected from mining events near New 19Ollerton, Nottinghamshire, we illustrate the effects proximity has on travel path velocities and 20 attenuation, then perform a damped least squares inversion to determine appropriate constants 21 within the M L scale. We show that the attenuation term needs to increase from 0.00183 to 0.0514, 22 and demonstrate that this higher value is representative of a raypath within a slower, more 23 attenuating sedimentary layer compared to the continental crust. We therefore recommend that 24 the magnitude scale 1.17 0.0514 3.0 should be used when local 25 monitoring networks are within 5km of the event epicentres. 26

 Distributed acoustic sensing can outperform geophones for source spectra and fullwaveform source mechanism inversion  2D distributed acoustic sensing array geometries can be used as a multi-component sensor capable of measuring shear-wave splitting  Larger surface distributed acoustic sensing deployments and/or hybrid networks are required for accurate microseismic detection/location Accepted ArticleThis article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

Free radicals may impair vital functions of several types of tissues including coronary artery smooth muscle. Because the Na+ pump plays a key role in maintaining coronary tone, the effects of superoxide and peroxide on this protein were examined. Ouabain-sensitive Rb+ uptake by denuded coronary artery rings was used in lieu of K+ transport by this pump. It was inhibited by exposing the rings for 90 min either to peroxide [50% inhibitory concentration (IC50) = 0.56 +/- 0.18 mM] or to superoxide generated by xanthine oxidase (XO; 0.3 mM xanthine and xanthine oxidase, IC50 = 0.08 +/- 02 mU/ml). The effect of peroxide was not overcome by superoxide dismutase and that of superoxide was not prevented by catalase. K(+)-activated ouabain-sensitive hydrolysis of p-nitrophenyl phosphate in the plasma membrane-enriched fraction isolated from the coronary artery smooth muscle was monitored as the hydrolytic activity of the Na+ pump. It was inhibited by exposing the membranes only to very high concentrations of peroxide (IC50 = 9.85 +/- 3.5 mM) or XO (IC50 = 5 +/- 2 mU/ml). The exposure to 2.5 mM H2O2 or 0.5 mU/ml XO reduced the Na(+)-dependent acylphosphate levels only by 41 +/- 3 and 30 +/- 4%, respectively even though either inhibited the Rb+ uptake by > 80%. Thus superoxide and peroxide uncoupled the hydrolytic activity of the Na+ pump from Rb+ uptake. We speculate that such an uncoupling in ischemia and reperfusion would result in dual damage: ion imbalance and continuous hydrolysis of ATP in the cells that are already starved.

Local magnitudes calculated at stations less than 10 km from earthquakes in the British Isles are up to one unit of magnitude higher than local magnitudes calculated at more distant stations. This causes a considerable overestimate of the event magnitude, particularly for small events, which are only recorded at short distances. Data from Central Italy and Norway shows that the same problem also occurs in other regions, suggesting that this is a more general issue for local magnitude scales. We investigate the addition of a new exponential term to the general form of the local magnitude scale. This corrects for the higher than expected amplitudes at short hypocentral distances. We find that the addition of this new term improves magnitude estimates in the three studied regions and magnitudes at short distances are no longer overestimated. This allows the use of a single scale that can be used at all distances, with a smooth transition between short and long distances. For the UK, the amended scale is log 1.11 log 0.00189 1.16. 2.09 and this is the scale now used by the British Geological Survey.

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