Abstract Grain size distribution (GSD) data are widely used in Earth sciences and although large sets regularly generated, detailed numerical analyses not routine. Unmixing GSDs into components can help understand sediment provenance depositional regimes/processes. End‐member analysis (EMA), which fits one set of end‐members to a given set, is powerful way unmix geologically meaningful parts. EMA estimates based on covariability within be considered as nonparametric approach. Available...

The selection of paleointensity data is a challenging, but essential step for establishing reliability. There is, however, no consensus as to how best quantify and which processes are most effective. To address these issues, we begin lay the foundations more unified theoretically justified approach data. We present new compilation standard definitions statistics help remove ambiguities in their calculation. also compile largest-to-date set raw from historical locations laboratory control...

Significance A wide range of organisms sense Earth’s magnetic field for navigation. For some organisms, like magnetotactic bacteria, particles form inside cells and act a compass. However, the origin behavior remains mystery. We report that magnetotaxis evolved in bacteria during Archean, before or near divergence between Nitrospirae Proteobacteria phyla, suggesting are one earliest magnetic-sensing biomineralizing on Earth. The early would have provided evolutionary advantages coping with...

The method behind the UK Display Energy Certificate (DEC) improves comparability of benchmarking by accounting for variations in weather and occupancy. To improve further, incorporation other features that are intrinsic to buildings (e.g. built form building services) deserve exploration. This study investigates impact these explores ways further energy performance schools. Statistical analyses approximately 7700 schools were performed, followed causal factors 465 greater detail using...

Abstract The origin and evolution of magnetoreception, which in diverse prokaryotes protozoa is known as magnetotaxis enables these microorganisms to detect Earth’s magnetic field for orientation navigation, not well understood evolutionary biology. only capable sensing the geomagnetic are magnetotactic bacteria (MTB), motile that biomineralize intracellular, membrane-bounded single-domain crystals either magnetite (Fe3O4) or greigite (Fe3S4) called magnetosomes. Magnetosomes responsible...

Abstract Magnetic hysteresis loops are important in theoretical and applied rock magnetism with applications to paleointensities, paleoenvironmental analysis, tectonic studies, among many others. Information derived from these data is the most ubiquitous magnetic used by Earth science community. Despite their prevalence, there no general guidelines aid scientists obtaining best possible widely available software allow efficient analysis of loop using advanced appropriate methods. Here we...

[1] Detecting and excluding non-ideal behavior during paleointensity experiments is critical to asserting the reliability of data. Our knowledge detecting behavior, in particular influence multidomain (MD) grains, has expanded considerably over past decade experimental procedures now commonly incorporate checks detect effects MD behavior. However, many older studies were carried out before these devised provide no quantifiable means testing for presence grains. An estimated one third all...

Records of reversal frequency support forcing the geodynamo over geological timescales but obtaining these for earlier times (e.g. Precambrian) is a major challenge. Changes in measured virtual (axial) dipole moment Earth, averaged several millions years or longer, also have potential to constrain core and mantle evolution through deep time. There been wealth recent innovations palaeointensity methods, there is, as yet, no comprehensive means assessing reliability new existing data. Here we...

Abstract We present results for a series of hysteresis measurements that provide information about remanent, induced, transient‐free, and transient magnetization components. These measurements, differences between measurement types, enable production six types first‐order reversal curve (FORC)‐like diagrams which only double the number involved in conventional FORC measurement. can be used to distinguish magnetic signatures associated with each domain state. When analyzing samples complex...

Abstract A broad range of organisms, from prokaryotes to higher animals, have the ability sense and utilize Earth's geomagnetic field—a behavior known as magnetoreception. Although our knowledge physiological mechanisms magnetoreception has increased substantially over recent decades, origin this remains a fundamental question in evolutionary biology. Despite this, there is growing evidence that magnetic iron mineral biosynthesis by may represent earliest form biogenic sensors on Earth....

Abstract Background The discovery of membrane-enclosed, metabolically functional organelles in Bacteria has transformed our understanding the subcellular complexity prokaryotic cells. Biomineralization magnetic nanoparticles within magnetosomes by magnetotactic bacteria (MTB) is a fascinating example organelles. Magnetosomes, as nano-sized sensors MTB, facilitate cell navigation along local geomagnetic field, behaviour referred to magnetotaxis or microbial magnetoreception. Recent novel MTB...

Abstract The global paleointensity database for 65–200 Ma was analyzed using a modified suite of quality criteria (Q PI ) such that the likely reliability measurements is assessed objectively and as consistently possible across diverse data set. This interval chosen because dramatic extremes geomagnetic polarity reversal frequency ranging from greater than 10 reversals per million years in Jurassic hyperactivity period (155–171 Ma) to effectively zero during Cretaceous Normal Superchron...

SUMMARY Palaeomagnetic field intensity measurements, derived from rocks with ages that span geological time, provide a crucial constraint on the evolution of Earth’s deep interior and its magnetic environment. The palaeointensity database PINT has been updated to version v.8.0.0 includes site-mean records spanning an interval 50 ka 4.2 Ga, compiling efforts palaeomagnetic community 1959 end 2019. Nearly all have assessed using qualitative reliability (quality palaeointensity, QPI) framework....

Whether there are links between geomagnetic field and Earth's orbital parameters remains unclear. Synchronous reconstructions of parallel long-term quantitative climate change records rare. Here, we present 10Be-derived changes both Asian monsoon (AM) rainfall over the last 870 kyr from Xifeng loess-paleosol sequence on central Chinese Loess Plateau. The 10BeGM flux (a proxy for field-induced 10Be production rate) reveals 13 consecutive excursions in Brunhes chron, which synchronized with...

Abstract Micromagnetic modeling allows the systematic study of effects particle size and shape on first‐order reversal curve (FORC) magnetic hysteresis response for magnetite particles in single‐domain (SD) pseudo‐single domain (PSD) range. The interpretation FORCs, though widely used, has been highly subjective. Here, we use micromagnetics to model randomly oriented distributions allow more physically meaningful interpretations. We show that one commonly found type PSD particle—namely...

Abstract First‐order reversal curve (FORC) diagrams are a standard rock magnetic tool for analyzing bulk hysteresis behaviors, which used to estimate the mineralogies and domain states of grains within natural materials. However, interpretation FORC distributions is challenging due complex domain‐state responses, introduce well‐documented uncertainties subjectivity. Here, we propose neural network algorithm (FORCINN) invert size aspect ratio distribution from measured data. We trained tested...

Néel's theory of single domain magnetizations has been widely applied in paleomagnetism since its conception the 1940s. When applying this theory, paleomagnetists typically assume that all magnetic particles are composed magnetite, and shaped like highly elongate needles. Even SD size range, natural samples exhibit a much wider range morphologies, causing gap between experiments. Although these assumptions were necessary 1940s, computing power today means they no longer...

Magnetic hysteresis measurements are widely used in Earth and planetary sciences with the aim of identifying geologically meaningful magnetic recorders, to study variations present past environments. The interpretation data terms domain state paleomagnetic stability major motivations behind undertaking these measurements, but fraught challenges ambiguities. We have undertaken a systematic micromagnetic quantify behavior room-temperature magnetite as function particle size (45–195...

Abstract The Holocene Warm Period (HWP) provides valuable insights into the climate system and biotic responses to environmental variability thus serves as an excellent analogue for future global changes. Here we document, first time, that warm wet HWP conditions were highly favourable magnetofossil proliferation in semi-arid Asian interior. pronounced increase of concentrations at ~9.8 ka decrease ~5.9 Dali Lake coincided respectively with onset termination are linked increased nutrient...

Non-heating palaeointensity methods are a vital tool to explore magnetic field strength variations recorded by thermally sensitive materials of both terrestrial and extraterrestrial origin. One such method is the calibrated pseudo-Thellier in which specimen's natural remanent magnetization alternating demagnetized replaced with laboratory induced anhysteretic (as an analogue thermoremanent magnetization, TRM). Using set 56 volcanic specimens given TRMs fields 10–130 μT, we refine calibration...

The bottom-up methods for energy benchmarking aim to derive a yardstick performance based on theoretical analysis of building. While the top-down drive improvement by ranking building against its peers, are focused building’s specific context. Consequently, can help identify how could be materialised. These two complementary approaches improve design practice and facilities’ management. Two that used have been reviewed using UK schools as case studies: Building physics aggregated end-use. is...