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During the analog era of seismology, seismograms were typically written to paper media. The legacy records from this era make up an irreplaceable resource that covers over a century, and many of them remain extant in both their original paper form and as microformat copies. While microformat copies of seismograms drove decades of seismological research, new capabilities have been developed that allow us to revisit the analog data sets and extend application of contemporary analyses to a considerably longer seismological record. Though microformat seismogram copies have been extensively used, we seek to understand possible differences that could arise from using data recovered from such copies compared to using the original seismograms. Identification of these differences provides understanding of the fidelity of information that is recoverable from these different media. We present a case study here, applying a number of quantitative measures to a pair of records (original paper and its 35 mm microfilm copy), and revealing that microfilm-derived time series differ from the original paper in timing and amplitude. Based on a simple analysis of this pair of short-period vertical records, we estimate uncertainties of ±0.1–0.3 for earthquake magnitude (hence, a factor of about 1.3–2.0 in energy) and ±10 km for hypocentral location.

This experimental work was done before the stopping the Baikalsk Paper and Pulp Mill. As the informative criteria for the present state of anthropogenic soils used in this study the degree of their biochemical activity and the acid-alkaline conditions which belong to integral indicators was taken. The basic technique for carrying out mass analyses of biochemical activity of soils characterizing the territory of the city of Baikalsk was the rapid analysis method suggested by T. V. Aristovskaya and M. V. Chugunova. The study revealed a high level of soil activity in all functional zones of the city. The acid-alkaline contents were determined for the soils under investigation, which showed a wide range of values (from 6,7 to 8,5 рН). On the basis of the data obtained and point measurements in the geoinformation environment the IDW Nearest Neighbors method was used to construct isopleth maps. A trend for a weak but positive correlation was revealed between the acid-alkaline conditions and soil biochemical activity. All the findings provide a basis for further monitoring the post-technogenic recovery of the city’s soil ecological status in the setting of Southern Baikalia.

We would like to make some comments on the paper by Hamidatou et al. (2019). Initially, these comments are motivated to reveal that, previous results on probabilistic seismic hazard analyses, some of them computed and published by our research group, are wrongly quoted in the paper by these authors. In our opinion, some other points are worthy of debate, mainly, but not only, the used seismic source zone model, the used logic-tree, and also the comparison of estimated values of peak ground horizontal acceleration (PGA) with previous results.

Insolation calculations for solving the two-body problem have been analyzed. The errors associated with the simplification of the calculation algorithm of insolation and disregard (simultaneously) of the attraction of planets of the solar system and their satellites in calculations of the Earth’s irradiation have been indicated. The use of the method of equivalent latitudes in paleoclimatology has been shown to be inconsistent. The need to take into account changes in the meridional insolation gradient, which regulates the meridional heat transfer from the equator to polar regions, in paleoclimatology and paleogeography has been substantiated.

Studies on the influence of paper mill wastewater, which affects photosynthesis, on reed chlorophyll and biomass can provide a theoretical basis for the ecological restoration of wetland plants. The influence of different concentrations of wastewater (chemical oxygen demands (COD) of 300, 175 and 50 mg•L−1) and different irrigation times (germination, blade-expansion, rapid-growth, heading and maturity stages) on the contents of chlorophyll a, chlorophyll b, total chlorophyll and chlorophyll a/b in reeds were tested in experimental pools that simulated the wetland ecosystem of the Liaoning Shuangtai estuary. The contents of chlorophyll a, chlorophyll b, total chlorophyll and chlorophyll a/b all increased significantly with increasing concentrations of wastewater, and their contents all differed significantly from each other. The contents of chlorophyll a, chlorophyll b and total chlorophyll were maximal when irrigated at the beginning of all growth stages with COD of 300 mg•L−1(C1O) at 2.253, 0.458 and 2.711 mg•g−1 fresh weight (FW), respectively, with irrigation at the rapid-growth stage and were minimal in the control plants at 0.142, 0.068 and 0.210 mg•g−1 FW, respectively, with irrigation at maturity. Chlorophyll a/b was maximal at C1O at 5.753 with irrigation at germination stage and was minimal in the control plants at 2.113 with irrigation at maturity. Reed biomass was maximal at C1O at 3.26 kg, which was 2.76 times higher than the control. Reed biomass was positively correlated with the content of chlorophyll and with COD in the wastewater. Paper mill wastewater generally increased the content of chlorophyll and the net photosynthesis rate and enhanced the growth of reeds.

The geological model of large hydrothermal salt accumulations linked to "Wilson cycles" as reviewed by Hovland and Coworkers, un-adequately addressed: (1) the lack of well exposed submarine volcanogenic hydrothermal feeder zone, (2) the sequential precipitation of different hydrothermal evaporite minerals and (3) the absence of hydrothermal alteration mineralogy around the major evaporites. These aforementioned points are the main classical features to be linked to the hydrothermal model of evaporites. Experimentally, heating seawater during submarine volcanism firstly results in precipitation of anhydrite followed by halite, other evaporite minerals, serpentine, brucite, talc, metallic sulfides-oxides and related hydrothermal alterations. In this regard, Mg/Ca – Cl, Mg/Ca – SO4, Mg/Ca – Na/Cl and Mg/Ca - TDS biplots show that hydrothermal brines of riftogenic and subduction zone settings plot in a separate field than the subduction-related Andean Salars as well as seawater. This indicates that the hydrothermal serpentinization of basaltic oceanic crust and mantle peridotites removes magnesium from seawater and incorporates the Mg into serpentine, brucite and other hydrous Mg-silicates rather than the hydrothermal brines. Finally, our comment arose from a recent global classification of the most distinguished marine, non-marine and exhalative hydrothermal evaporites.

Based on shallow geophysical data, Klanica et al. (2020, ) argued that the deepest undewater cave in the world, the Hranice Abyss (HA) had formed by epigenic karstification related to mid-Miocene opening of similar to 1 km deep Carpathian Foredeep (CF) and, hence, could be similar to 1 km deep. However, the CF subsided and the abyss was uplifted due to post mid-Miocene faulting with at least 460 m vertical offset, which makes the depth estimate of Klanica et al. (2020, ) invalid. It remains unclear under which geological circumstances the HA, if formed by epigenic karstification, could be backfilled with water column reaching similar to 400 m of height.

In this communication we provide our answers to the comments by Usoskin (2017) on our recent paper (Popova et al, 2017a). We show that Principal Component Analysis (PCA) allows us to derive eigen vectors with eigen values assigned to variance of solar magnetic field waves from full disk solar magnetograms obtained in cycles 21–23 which came in pairs. The current paper (Popova et al, 2017a) adds the second pair of magnetic waves generated by quadruple magnetic sources. This allows us to recover a centennial cycle, in addition to the grand cycle, and to produce a closer fit to the solar and terrestrial activity features in the past millennium.

Paper board with bending stiffness is usually used as the substrates on cigarette package printing industry. The vibration of these paper boards in high speed affects the printing precision. The dynamic characteristics and stability of moving paper board with finite interior elastic point supports and elastic edges restrained are investigated. First, the energy function of the system is established by using the extended Hamilton’s principle; second, the dimensionless equations of motion for the moving paper board are obtained using the element-free Galerkin method. The equations of motion and the eigenvalue equations of the system are established. The relationship between the first three complex frequencies of the system and the moving speed is then obtained by the numerical calculation. The effects of the elastic point supports, the elastically restrained edges, and the dimensionless speed of the motion on the dynamic stability of the paper board are analyzed. The critical speed when the paper board is in a stable state under different conditions is obtained. The results improve the dynamic stability of the paper board in printing process and provide the theoretical basis for the optimization of printing equipment.

The paper by Schito et al. (2017) contains many misquotations of the regional literature on the Holy Cross Mountains, that may confuse the reader. Present comment suggests more appropriate references related to the stratigraphic, tectonic and palaeothermal aspects of the commented paper. The burial-thermal history as interpreted by Schito et al. is based on doubtful, poorly documented or even unsubstantiated thermal maturity and stratigraphical data, ignoring important regional evidence, such as Caledonian (sub-Devonian) unconformity and Permian thermal anomaly. The 1-D modeling study performed by Schito et al. (2017) did not consider published alternative concepts of the temporal and spatial heat flow patterns. The resulting models, assuming uniformly low heat flow between the Ordovician and the earliest Cretaceous, are inconsistent with independent regional data pointing to a hotter Variscan (Carboniferous-Permian) thermal regime.

All authors want their submitted papers to have maximum impact. Perhaps the greatest compliment you can earn as an author is to have your paper cited by other authors whom you respect. The impact of your paper can be on your professional reputation, your company’s ability to solicit customers and/or enlist partners, and if you are a university or government employee, on your yearly performance evaluation. For these reasons, authors sometimes consider journals’ impact factors when deciding to which journal they will submit. Institutions often use impact factors when evaluating professors for tenure. Librarians often consider them when making subscription decisions. Where did impact factors originate, and what do these numbers really mean?

This special issue presents a selection of extended and thoroughly revised papers resulting from the 10th (IMC) International Masonry Conference, which took place at the Technical University of Milan (Politecnico di Milano) in Milan, Italy from 9 to 11 July 2019.

International audience; Earthquakes nucleate when large amounts of elastic energy, stored in the earth's crust, are suddenly released due to abrupt sliding over a fault. Fluid injections can reactivate existing seismogenic faults and induce/trigger earthquakes by increasing fluid pressure. Here we develop an analogous experimental system of simultaneously loaded and wetted absorbent porous paper to quantify theoretically the process of wetting-induced earthquakes. This strategy allows us to gradually release the stored energy by provoking low intensity tremors. We identify the key parameters that control the outcome of the applied injection strategy, which include the initial stress state, fault segmentation, and segment-activation rate. Subsequent injections, initiated at high stress levels, can drive the system faster toward its instability point, nucleating a large earthquake. Starting at low stress levels, however, they can reduce the magnitude of the natural event by at least one unit.

A recent publication on the Jurassic-Cretaceous transition in carbonate platforms of NE Turkey reported some major discontinuities. Based on biostratigraphy and Sr-derived ages, one associated hiatus was estimated spanning the Tithonian whereas the remaining three minor hiatuses are supposed to have occurred during the Hauterivian - Barremian interval. The revision of the material (foraminifers and calcareous algae) from the 2 localities studied led to identify Kimmeridgian strata below the discontinuity and Valanginian to ? lower Hauterivian strata above the discontinuity, but no upper Hauterivian or Barremian strata at the top of the section. The major stratigraphic gap possibly corresponds to the Berriasian and most, if not all, of the Tithonian at this location.

In the Russian school, the total normalized gradient method belongs to the most wide‐spread of direct interpretation methods for potential field data. This method was also used and partly developed by many experts from abroad. The main advantage of the total normalized gradient method is its relative independence of parameters such as the expected differential density of interpreted structures. The method is built from a construction of a specially transformed field (total normalized gradient) on a section crossing the potential field sources. The special properties of this transformed field allow it to be used to detect the source positions. From the 1960s, the mathematical basis of the method underwent enormous development and several modifications of the method have been elaborated. The total normalized gradient operator itself represents a relatively complicated, non‐linear band‐pass filter in the spectral domain. The properties of this operator can be handled by means of several parameters that act to separate the information about field sources at different depth levels. In this contribution, we describe the development of the method from its very beginning (based mostly on qualitative interpretation of simple total normalized gradient sections) through to more recent numerical improvements to the method. These improvements include the quasi‐singular points method, which refines the filter properties of the total normalized gradient operator and defines an objective criteria (so called criterion ‘α’ and ‘Г') for the definition of source depths in the section. We end by describing possibilities for further development of the method in the future.

We reformulate the original model of Hatchell and Bourne and Roste, Stovas and Landro that couples fractional velocity change to subsurface strain via a fundamental constant R. The new model combines elastic compressibility of a dual-porosity system for a sand–shale mixture with horizontal planes of inter-granular weakness. The majority of observed R-factor magnitudes from post-stack 4D seismic data in both the reservoir and overburden can thus be explained. R is predicted to depend strongly on lithology and also initial strain state. The model is also extended to predict the observed angle-dependence of time-lapse time-shifts from pre-stack data. An expression for the gradient of time-shift with incidence angle is obtained in terms of the background VP/VS, and also the ratio of tangential to normal compliances BT/BN representing loss or creation of inter-granular coupling. If accurately estimated from data, this compliance ratio can be used as an additional parameter to assess the post-production state of the overburden. It is concluded that whilst R remains the over-arching parameter controlling the magnitude of time-shifts measured from 4D seismic data, BT/BN is a subtler parameter that may also prove of future value.

High-impact review papers describe and synthesize the current state of the art, the open questions and controversies, and provide ideas for future investigations. They are written not only for a specific scientific discipline but also for the broader Earth and space science community. They not only summarize the literature, but they also create a framework from which to understand the progress, problems, and connections between different communities, observations, models, and approaches. Here we describe how to write a high-impact review paper, and why you should consider writing one for Reviews of Geophysics.

In Part I of this paper, we defined a focusing wave field as the time reversal of an observed point‐source response. We showed that emitting a time‐reversed field from a closed boundary yields a focal spot that acts as an isotropic virtual source. However, when emitting the field from an open boundary, the virtual source is highly directional and significant artefacts occur related to multiple scattering. The aim of this paper is to discuss a focusing wave field, which, when emitted into the medium from an open boundary, yields an isotropic virtual source and does not give rise to artefacts. We start the discussion from a horizontally layered medium and introduce the single‐sided focusing wave field in an intuitive way as an inverse filter. Next, we discuss single‐sided focusing in two‐dimensional and three‐dimensional inhomogeneous media and support the discussion with mathematical derivations. The focusing functions needed for single‐sided focusing can be retrieved from the single‐sided reflection response and an estimate of the direct arrivals between the focal point and the accessible boundary. The focal spot, obtained with this single‐sided data‐driven focusing method, acts as an isotropic virtual source, similar to that obtained by emitting a time‐reversed point‐source response from a closed boundary.

The northern Bay of Bengal velocity-depth profiles do not follow the velocity-depth curve of the North Atlantic volcanic margins, and only partially the Kerguelen velocity-depth curves. Deep seismic refraction and reflection profiles acquired across the Hatton bank and Feroes ridge show that the melt is intruded into the lower thinned continental crust as sills, which cross-cut the continental fabric rather than underplating as it was often assumed in the past. Compared with the SCS northern margin proxy, we still suggest that the BoB crust is thinned continental crust intruded by post-rifting volcanics, as also shown by the interpretation of the numerous high-quality deep MCS profiles we collected there. What was supposed to be underplating might be sills intruded through the lower thinned continental crust.

Osseointegration of biomedical implants as well as healing of broken bones are supported by novel bioceramic materials that, owing to their engineered ionic conductivity, in the presence of an electric field provide accumulation of negative electrical charges close to the interface between an implant and living bone tissue, thus stimulating the rate of bone growth. In this position paper, the structure as well as the chemical, electrical, and biomedical properties of Ca (Ti,Zr) hexaorthophosphates are reviewed. In addition, based on evaluation of the material’s properties, a conceptual configuration of a capacity-coupled bone growth stimulator will be presented. The advantage of the proposed novel device over already existing bone-growth stimulators is its provision of the intimate contact of a capacity-coupled electric field with the growing bone tissue as opposed to an externally applied inductively coupled electromagnetic field, which suffers substantial attenuation when transmitted through soft tissue covering the locus of bone growth. To achieve higher ionic conductivity in Ca (Ti,Zr) hexaorthophosphates, aliovalent doping with highly mobile Na or Li ions intercalated into the only partially occupied M1 sites appears to be a suitable route.

This is a comment on the paper ‘Historical seismicity in the Middle East: new insights from Ottoman primary sources (sixteenth to mid-eighteenth centuries)’ by Guclu Tuluveli (JOSE, 2015, vol. 19, 1003–1008). The authors comment on the sources for each of the events cited by Guclu Tuluveli, providing for the non-specialist a better sense of how the events he lists might more accurately fit into existing knowledge of the historical seismicity of the Ottoman lands.

Phosphorus is the central ingredient in fertilizer that allows modern agriculture to feed the world’s population. This element, also critical in a host of industrial applications, is a nonrenewable resource that is sourced primarily from the phosphatic mineral apatite, hosted in sedimentary and igneous ores. World phosphate resources are estimated by the U.S. Geological Survey at ca. 300,000 Mt, of which 95% are sedimentary and 5% are igneous. Current known USGS reserve estimates are sufficient for a maximum of 200 to 300 years; the exploration and discovery of new resources, enhanced mining technologies, and new technologies aimed at the recovery and recycling of P from sewage and agricultural runoff will all contribute to extending P production. Igneous ores are generally associated with Phanerozoic carbonatites and silica-deficient alkalic intrusions that typically average 5 to 15 wt % P 2 O 5 , which can be beneficiated to high-grade concentrates of at least 30 wt % P 2 O 5 with few contaminants. Carbonatites are typically the smallest and youngest parts of a carbonatite-alkaline rock complex that formed during fractional crystallization of a calcic parental alkaline silicate melt, or from liquid immiscibility of a carbonate-rich nephelinite that underwent magmatic fractionation and differentiation during ascent from the mantle source. Fluorapatite generally crystallizes early, near the liquidus, and over a small temperature interval below the apatite saturation temperature that varies strongly with temperature, SiO 2 and CaO concentrations, and the aluminosity of the melt. Carbonatite-alkaline rock complexes commonly possess a concentric, zonal structure thought to reflect caldera volcanism. Pathfinder elements in soils, sediments, tills, and vegetation include Nb, rare earth elements (REEs), P, Ba, Sr, F, U, and Th, and in water, F, Th, and U are indicators. Remote sensing techniques with the ability to identify minerals rich in CO 3 , REEs, and Fe 2+ that are characteristic of carbonatites are also important exploration tools that may provide vectors to ore. Sedimentary phosphorite is a marine bioelemental sedimentary rock that contains >18 wt % P 2 O 5 . While small peritidal phosphorites formed in Precambrian coastal environments, economically significant upwelling-related phosphorite did not accumulate until the late Neoproterozoic and continued through the Phanerozoic. Coastal upwelling delivered deep, P-rich waters to continental shelves and in epeiric seas to drive phosphogenesis and form the largest phosphorites on Earth. High-grade deposits formed as a result of hydraulic concentration of phosphate grains to form granular beds with minimal gangue. The amalgamation of these beds into decameter-thick, stratiform ore zones is generally focused along the maximum flooding surface, which is a primary exploration target in upwelling-related phosphorite. In addition to P, other elements concentrated in igneous and sedimentary phosphorites are Se, Mo, Zn, Cu, and Cr, which are important agricultural micronutrients. Other saleable by-products include U and REEs. The U concentration in sedimentary phosphorite is generally between 50 and 200 ppm, but can be as high as 3,000 ppm, making it an increasingly important source of U for the nuclear industry. The concentration of REEs in some sedimentary phosphorites is comparable to the world’s richest igneous and Chinese clay-type REE deposits. The source of the dissolved P in upwelling ocean water is ultimately derived from the chemical weathering of continental rocks, the process that links igneous and sedimentary phosphorites through time and space. The covarying temporal relationship of igneous and sedimentary deposits suggests that plate tectonics and the concentration of apatite in a progressively more felsic crust underpins the feedback processes regulating the biogeochemical cycling of P. Critical to the generation of greenfield exploration targets is the recognition that large P deposits emerged in the late Neoproterozoic. The geological environments conducive for exploration can be constrained from an understanding of ore-forming processes by the use of complementary petrological techniques, including fieldwork, petrography, sedimentology, sequence stratigraphy, and geochemistry.