Calcite is a common mineral precipitated within upper crustal fault zones and associated fractures, forming veins, cements coatings. It has the potential to be dated using several radioisotopic systems if parent/daughter isotope abundances are suitable for currently available analytical techniques. U-Pb dating can most readily achieved in-situ laser ablation technique, which led rapid growth ar...

We summarize geochemical, astronomical, and theoretical constraints on the lifetime of the protoplanetary disk. Absolute Pb-Pb-isotopic dating of CAIs in CV chondrites (4567.2 ± 0.7 m.y.) and chondrules in CV (4566.7 ± 1 m.y.), CR (4564.7 ± 0.6 m.y.), and CB (4562.7 ± 0.5 m.y.) chondrites, and relative Al-Mg chronology of CAIs and chondrules in primitive chondrites, suggest that high-temperatur...

[1] We analyze the count rates of two terrestrial gamma‐ray flashes (TGFs) detected by the Fermi Gamma‐ray Burst Monitor (GBM) with the broadband magnetic fields (1 to 300 kHz) produced by the simultaneous lightning processes. The microsecond‐scale absolute time accuracy for these data, combined with independent geolocations of the source lightning, enable this analysis with higher accuracy tha...

The North Pacific thermocline (250 to 400 m) is studied using XBT observations acquired during the 1970s and 1980s. Interannual variations (3–5 yr timescales) in thermocline temperature, with O(0.18C) amplitude at 400 m, are found to exhibit westward propagation throughout the extratropical North Pacific up to 458N. Southward of 308N, the features propagate intact across the basin from the east...

The timescale for galaxies within merging dark matter halos to merge with each other is an important ingredient in galaxy formation models. Accurate estimates of merging timescales are required for predictions of astrophysical quantities such as black hole binary merger rates, the build-up of stellar mass in central galaxies, and the statistical properties of satellite galaxies within dark matt...