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Decades of studies at divergent plate margins have revealed networks of magmatic sills at the crust-mantle boundary. However, a lack of direct observations of deep magma motion limits our understanding of magma inflow from the mantle into the lower crust and the mechanism of sill formation. Here, satellite geodesy reveals rift-scale deformation caused by magma inflow in the deep crust in the Afar rift (East Africa). Simultaneous inflation of four sills, laterally separated by 10s of km and at depths ranging 9–28 km, caused uplift across a ~ 100-km-wide zone, suggesting the sills are linked to a common mantle source. Our results show the supply of magma into the lower crust is temporally episodic, occurring across a network of sills. This process reflects inherent instability of melt migration through porous mantle flow and may be the fundamental process that builds the thick igneous crust beneath magmatic rifts and rifted margins globally [ABSTRACT FROM AUTHOR]

On January 12, 2020, Taal volcano, Philippines, erupted after 43 years of repose, affecting more than 500,000 people. Using interferometric synthetic aperture radar (InSAR) data, we present the pre‐ to post‐eruption analyses of the deformation of Taal. We find that: (1) prior to eruption, the volcano experienced long‐term deflation followed by short‐term inflation, reflecting the depressurization‐pressurization of its ∼5 km depth magma reservoir; (2) during the eruption, the magma reservoir lost a volume of 0.531 ± 0.004 km3 while a 0.643 ± 0.001 km3 lateral dike was emplaced; and (3) post‐eruption analyses reveal that the magma reservoir started recovery approximately 3 weeks after the main eruptive phase. We propose a conceptual analysis explaining the eruption and address why, despite the large volume of magma emplaced, the dike remained at depth. We also report the unique and significant contribution of InSAR data during the peak of the crisis. Plain Language Summary: Taal volcano in the Philippines erupted on January 12, 2020. Here, we present the pre‐, co‐, and post‐eruption data, model, and analyses using interferometric synthetic aperture radar (InSAR) data acquired by various satellite systems. We find that: (1) prior to the eruption, the volcano experiences a sequence of long‐term (>1 year) deflation followed by short‐term (≤1 year) inflation as a result of the depressurization‐pressurization of its ∼5 km depth magma reservoir; (2) during the eruption, the magma reservoir lost a volume of 0.531 ± 0.004 km3 while a 0.643 ± 0.001 km3 lateral dike was emplaced; and (3) post‐eruption analyses reveal that the magma reservoir is in recovery starting ∼3 weeks after the main eruptive phase. We propose a conceptual analysis to explain the 2020 Taal eruption and the dike emplacement. We also report the unique and significant contribution of remote sensing data, particularly InSAR during the peak of the crisis. Key Points: We present a comprehensive interferometric synthetic aperture radar (InSAR)‐based data, analyses, and models of Taal's pre‐ to post‐eruptive stateDuring the eruptive crisis, Taal's magma reservoir lost 0.531 ± 0.004 km3 of volume while a 0.643 ± 0.001 km3 lateral dike was emplacedLow‐latency InSAR‐derived products provided crucial and significant information to PHIVOLCS during the January 2020 eruptive event [ABSTRACT FROM AUTHOR]

Last two decades have proven that remote sensing represents a key tool to improve our knowledge of volcanic systems but also to monitor active volcanoes. Based on the specific case of Piton de la Fournaise, Reunion Island, the most active French volcanoes, we here illustrate how Synthetic Aperture Radar (SAR) data, providing information even in cloudy conditions, make it possible to map eruptive deposits, to quantify their volumes but also to estimate the volcanoes topography (with metric precision) as well as surface deformation fields (with a precision reaching a few millimeters). [ABSTRACT FROM AUTHOR]

Background: Zoledronate prevents fractures in older women when administered every 12 to 18 months, but its effects on bone density and bone turnover persist beyond 5 years. Whether infrequent zoledronate administration would prevent vertebral fractures in early postmenopausal women is unknown., Methods: We conducted a 10-year, prospective, double-blind, randomized, placebo-controlled trial involving early postmenopausal women (50 to 60 years of age) with bone mineral density T scores lower than 0 and higher than -2.5 (scores of -1 or higher typically indicate normal bone mineral density) at the lumbar spine, femoral neck, or hip. Participants were randomly assigned to receive an infusion of zoledronate at a dose of 5 mg at baseline and at 5 years (zoledronate-zoledronate group), zoledronate at a dose of 5 mg at baseline and placebo at 5 years (zoledronate-placebo group), or placebo at both baseline and 5 years (placebo-placebo group). Spinal radiographs were obtained at baseline, 5 years, and 10 years. The primary end point was morphometric vertebral fracture, which was assessed semiquantitatively and defined as at least a 20% change in vertebral height from that seen on the baseline radiograph. Secondary end points were fragility fracture, any fracture, and major osteoporotic fracture., Results: Of 1054 women with a mean age of 56.0 years at baseline, 1003 (95.2%) completed 10 years of follow-up. A new morphometric fracture occurred in 22 women (6.3%) in the zoledronate-zoledronate group, in 23 women (6.6%) in the zoledronate-placebo group, and in 39 women (11.1%) in the placebo-placebo group (relative risk, zoledronate-zoledronate vs. placebo-placebo, 0.56 [95% confidence interval {CI}, 0.34 to 0.92; P = 0.04]; and zoledronate-placebo vs. placebo-placebo, 0.59 [95% CI, 0.36 to 0.97; P = 0.08]). The relative risk of fragility fracture, any fracture, and major osteoporotic fracture was 0.72 (95% CI, 0.55 to 0.93), 0.70 (95% CI, 0.56 to 0.88), and 0.60 (95% CI, 0.42 to 0.86), respectively, when zoledronate-zoledronate was compared with placebo-placebo and 0.79 (95% CI, 0.61 to 1.02), 0.77 (95% CI, 0.62 to 0.97), and 0.71 (95% CI, 0.51 to 0.99), respectively, when zoledronate-placebo was compared with placebo-placebo., Conclusions: Ten years after trial initiation, zoledronate administered at baseline and 5 years was effective in preventing morphometric vertebral fracture in early postmenopausal women. (Funded by the Health Research Council of New Zealand; Australian New Zealand Clinical Trials Registry number, ACTRN12612000270819.)., (Copyright © 2025 Massachusetts Medical Society.)

Organic nitrates have been reported to have significant effects on bone mineral density (BMD) and bone turnover in previous clinical trials. However, results are inconsistent and some trials with strikingly positive results have been retracted because of scientific misconduct. As preparation for a potential fracture prevention study, we set out to determine the lowest effective dose and the most effective and acceptable nitrate preparation. We undertook a 1-year, double-blind, randomized, placebo-controlled trial of three different nitrate preparations and two different doses in osteopenic postmenopausal women, with a planned 1-year observational extension. The primary endpoint was change in BMD at the lumbar spine, and secondary endpoints included BMD changes at other sites, changes in bone turnover markers, and adverse events. A total of 240 eligible women who tolerated low-dose oral nitrate treatment in a 2-week run-in period were randomized to five different treatment groups or placebo. Over 12 months, there were no statistically significant between-group differences in changes in BMD at any site and no consistent differences in bone turnover markers. When the active treatment groups were pooled, there were also no differences in changes in BMD or bone turnover markers between nitrate treatment and placebo. Eighty-eight (27%) women withdrew during the run-in phase, with the majority because of nitrate-induced headache, and 41 of 200 (21%) women randomized to nitrate treatment withdrew or stopped study medication during the 1-year study compared with 1 of 40 (2.5%) in the placebo group. In summary, organic nitrates do not have clinically relevant effects on BMD or bone turnover in postmenopausal women and were poorly tolerated. These results call into question the validity of previous clinical research reporting large positive effects of nitrates on BMD and bone turnover. © 2020 American Society for Bone and Mineral Research., (© 2020 American Society for Bone and Mineral Research.)

Large volume effusive eruptions with relatively minor observed precursory signals are at odds with widely used models to interpret volcano deformation. Here we propose a new modelling framework that resolves this discrepancy by accounting for magma buoyancy, viscoelastic crustal properties, and sustained magma channels. At low magma accumulation rates, the stability of deep magma bodies is governed by the magma-host rock density contrast and the magma body thickness. During eruptions, inelastic processes including magma mush erosion and thermal effects, can form a sustained channel that supports magma flow, driven by the pressure difference between the magma body and surface vents. At failure onset, it may be difficult to forecast the final eruption volume; pressure in a magma body may drop well below the lithostatic load, create under-pressure and initiate a caldera collapse, despite only modest precursors.

The existence of possible deep connections between nearby volcanoes has so far only been formulated on the basis of correlation in their eruptive activities or geochemical arguments. The use of geodetic data to monitor the deep dynamics of magmatic systems and the possible interference between them has remained limited due to the lack of techniques to follow transient processes. Here, for the first time, we use sequential data assimilation technique (Ensemble Kalman Filter) on ground displacement data to evaluate a possible interplay between the activities of Grímsvötn and Bárðarbunga volcanoes in Iceland. Using a two-reservoir dynamical model for the Grímsvötn plumbing system and assuming a fixed geometry and constant magma properties, we retrieve the temporal evolution of the basal magma inflow beneath Grímsvötn that drops by up to 85% during the 10 months preceding the initiation of the Bárðarbunga rifting event. We interpret the loss of at least 0.016 km 3 in the magma supply of Grímsvötn as a consequence of magma accumulation beneath Bárðarbunga and subsequent feeding of the Holuhraun eruption 41 km away. We demonstrate that, in addition to its interest for predicting volcanic eruptions, sequential assimilation of geodetic data has a unique potential to give insights into volcanic system roots.