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Multifractal patterns across deep time: What measurement density reveals about Earth's history

Phys.org: Earth science - Thu, 03/05/2026 - 15:40

Much of our understanding of Earth's past is derived from stratigraphic records exposed in rock outcrops or recovered from drilled cores. These records span immense time intervals, from thousands to billions of years, and form the basis of geochronologies used to reconstruct geological, climatic, and environmental change. However, as a new study published in Communications Earth & Environment shows, these records are far from uniform.

Burned permafrost peatlands release carbon for years after wildfires, researchers find

Phys.org: Earth science - Thu, 03/05/2026 - 14:40

In the face of climate change, permafrost peatland wildfires could play more of a role in the destructive cycle of global warming, University of Alberta research suggests.

Improved estimates of storm water in sewers could help reduce flooding

Phys.org: Earth science - Thu, 03/05/2026 - 12:00

Recent University of Toronto Ph.D. graduate Gabrielle Migliato Marega (CivMin) has developed an improved tool for estimating how much water from heavy rains ends up in sanitary sewers. The tool is particularly useful in areas where accurate data about sewer flow rates is difficult to find, such as in low- and middle-income countries, where many new sewer systems are being built.

First principles understanding of single domain magnetizations - Part II: Non-ideal magnetic behavior in ideal single domain titanomagnetite

Geophysical Journal International - Thu, 03/05/2026 - 00:00

SummaryLouis Néel’s theory of magnetism, which describes a rock’s magnetization as being carried by “ideal” uniformly magnetized or single domain (SD) particles, has been a cornerstone of paleomagnetic studies for over seven decades and has enabled paleomagnetists to make plate tectonic reconstructions, date geological and archaeological materials, and recover the history of Earth’s magnetic field. Unfortunately, many geological samples produce experimental results that disagree with the predictions made by Néel theory. This “non-ideal” behavior is often associated with larger particles that are non-uniformly magnetized. In this paper, we use simulations based on Néel theory to demonstrate that non-ideal behavior is also expected in assemblages of SD particles with a range of sizes and shapes previously assumed to be ideal. This effect occurs over a relatively small range of shapes and sizes for magnetite, but a much wider range for titanomagnetites. Our results call into question the typical interpretation of SD particles as ideal magnetic carriers. Instead, we suggest that the geological stability of a rock’s magnetization is influenced not only by the domain state of the magnetic carriers, but also by their shape and composition. This has important implications for paleointensities (and cooling rate corrections thereof), paleodirections, and the dating of viscous magnetizations.

A wide-range thermodynamically consistent constitutive model for dynamic loading of partially saturated porous media

Geophysical Journal International - Thu, 03/05/2026 - 00:00

SummaryThis paper presents a novel thermodynamically consistent constitutive model for partially saturated porous rocks across a wide range of conditions. The material states generated behind the shock wave from an explosive source can vary significantly, ranging from crushed and melted rock near the source to a poroelastic medium in the far field. In the model, rock strength is determined by the effective pressure, which is calculated using two independent equations of state: one for the solid rock and another for the pore fluid. The model accounts for shock-induced liquefaction resulting from fluid pressure buildup in the pore spaces near the explosive source. Simultaneously, it describes the increase in wave propagation speed due to elastic pore contraction in both dry and partially saturated rocks. This model is applied to investigate how fluid saturation affects the amplitude and shape of the generated waves, as well as the residual stress surrounding the cavity formed by spherical explosions.

Irrigation gaps in weather models could skew air quality forecasts, study finds

Phys.org: Earth science - Wed, 03/04/2026 - 23:30

Outdoor air pollution is estimated to contribute to more than 100,000 premature deaths in the United States each year, according to the National Weather Service. Accurate air quality forecasts—designed to protect public health, alerting communities to dangerous levels of pollutants linked to asthma attacks, heart disease and premature death—are critical for helping people limit exposure and for guiding regulatory action.

Эффект сверхразрешения и критерий разрешимости для волн в анизотропных средах

Успехи физических наук - Wed, 03/04/2026 - 21:00

Э.Г. Локк, С.В. Герус, А.В. Садовников

Обсуждается возможность решения проблемы по преодолению дифракционного предела в анизотропных средах. Экспериментально и теоретически продемонстрировано возникновение эффекта сверхразрешения, при котором отчётливая тень от точечного объекта наблюдается на расстояниях, значительно превышающих значения, полученные из критерия разрешимости Рэлея. В частности, на примере дифракции спиновых волн с длиной волны λ доказана возможность возникновения отчётливой тени от сквозного отверстия в ферритовой плёнке диаметром d < λ на расстоянии L ⪢ λ. Установлено, что сверхнаправленное распространение волны и сверхразрешающая тень от объекта возникают в направлении нормали к изочастотной зависимости волны в точке перегиба. Сформулирован критерий разрешимости, позволяющий проводить оценочные расчёты для волн в анизотропных средах и подтверждающий возможность возникновения в них эффектов сверхнаправленности и сверхразрешения.

A framework to identify winter fallow arable lands through machine learning methods

Recent articles in Advances in Space Research - Wed, 03/04/2026 - 19:11

Publication date: Available online 2 March 2026

Source: Advances in Space Research

Author(s): Dan Li, Wenzuo Zhou, Yichen Hu, Xinyu Yao

Assessing the Impacts of Long-Term Weather Variability and Urban Development on Crop Production to Analyze Food Security in Iran

Recent articles in Advances in Space Research - Wed, 03/04/2026 - 19:11

Publication date: Available online 2 March 2026

Source: Advances in Space Research

Author(s): Mohammad Kazemi Garajeh, Khalil Valizadeh Kamran, Bakhtiar Feizizadeh, Behnam Khorrami