Geography

Early Jurassic belemnites from the Gondwana margin of the Southern Hemisphere –Sinemurian record from South Tibet
Belemnites (Order Belemnitida), a very successful group of Mesozoic coleoid cephalopods, dominated fossil coleoid assemblages throughout the Jurassic and Cretaceous. According to the current view, the phylogenetically earliest known belemnites have been reported from the lowermost Jurassic (Hettangian) of northern Europe. The earliest belemnites are characterized by low diversity and small-size...


Devonian to Permian evolution of the Paleo-Tethys Ocean: New evidence from U-Pb zircon dating and Sr-Nd-Pb isotopes of the Darrehanjir-Mashhad “ophiolites”, NE Iran
Middle to Late Paleozoic ophiolites, which are remnants of the Paleo-Tethys Ocean, are aligned in two main zones in northern Iran: Darrehanjir-Fariman-Mashhad, and Rasht in the north and Jandagh-Anarak ophiolites to the south. Our new U-Pb zircon dating results shows that the ~200km long Darrehanjir – Mashhad mafic-ultramafic body is not a single ophiolite but a composite igneous complex comp...
India-Madagascar paleo-fit based on flexural isostasy of their rifted margins
The present study contributes new constraints on, and definitions of, the reconstructed plate margins of India and Madagascar based on flexural isostasy along the western continental margin of India (WCMI) and the eastern continental margin of Madagascar (ECMM). We have estimated the nature of isostasy and crustal geometry along the two margins, and have examined their possible conjugate struct...


Ionospheric Tomography Using Automatic Dependent Surveillance Broadcast (ADS-B) Signals
Numerical modelling has demonstrated that ADS-B signals can be used to reconstruct two dimensional (2D) electron density maps of the ionosphere using techniques for computerized tomography (CT). Ray-tracing techniques were used to determine the characteristics of individual waves, including the wave path and the state of polarization at the satellite receiver. The modelled Faraday rotation was ...
Characterizing the Pre-Space-Age Ionosphere over Washington, D.C
The study of long-term changes requires researchers to identify relevant historical measurements; quantifying and quality-controlling these measurements becomes central to their utilization by broader communities. This pilot study reports on the evaluation of ionograms and their inversion from the decade prior to the Space Age. The ionograms were recorded on 35 mm film reels and archived at t...


Greenland Telescope Project --- Direct Confirmation of Black Hole with Sub-millimeter VLBI ---
A 12-m diameter radio telescope will be deployed to the Summit Station in Greenland to provide direct confirmation of a Super Massive Black Hole (SMBH) by observing its shadow image in the active galaxy M87. The telescope (Greenland Telescope: GLT) is to become one of the Very Long Baseline Interferometry (VLBI) stations at sub-millimeter (submm) regime, providing the longest baseline > 9,0...
Remote sensing of freshwater cyanobacteria: An extended IOP Inversion Model of Inland Waters (IIMIW) for partitioning absorption coefficient and estimating phycocyanin
Phycocyanin primarily exists in freshwater cyanobacteria. Accurate estimation of low phycocyanin concentration (PC) is critical for issuing an early warning of potential risks of cyanobacterial population growth to the public. To monitor cyanobacterial biomass in eutrophic inland waters, an approach is proposed to partition non-water absorption coefficient (at-w (λ)) into the contribution of c...

Quantification of L-band InSAR coherence over volcanic areas using LiDAR and in situ measurements
Interferometric Synthetic Aperture Radar (InSAR) is a powerful tool to monitor large-scale ground deformation at active volcanoes. However, vegetation and pyroclastic deposits degrade the radar coherence and therefore the measurement of 3-D surface displacements. In this article, we explore the complementarity between ALOS–PALSAR coherence images, airborne LiDAR data and in situ measurements ...
3D coseismic deformations and source parameters of the 2010 Yushu earthquake (China) inferred from DInSAR and multiple-aperture InSAR measurements
The coseismic deformation field related to the 2010 Mw6.9 Yushu earthquake (Qinghai, China) has been investigated by previous studies using the satellite differential interferometric synthetic aperture radar (DInSAR) method. However, one of the limiting factors in the conventional DInSAR is that it can measure only one-dimensional (1D) ground motion along the radar line of sight (LOS) direction...

Radiation damage to Kokchetav UHPM diamonds in zircon: Variations in Raman, photoluminescence, and cathodoluminescence spectra
We conducted detailed in-situ Raman, photoluminescence (PL) and cathodoluminescence (CL) studies on microdiamonds in a tourmaline-rich quartzofeldspathic rock from the Kokchetav Massif, Kazakhstan. The microdiamonds occur as inclusions in the cores of K-tourmaline and in zoned zircons with varying U contents. The results of 2D Raman mapping of zircon showed that the U-rich parts were more metam...
New petrological constraints on the last eruptive phase of the Sabatini Volcanic District (central Italy): Clues from mineralogy, geochemistry, and Sr–Nd isotopes
We report results from mineralogical, geochemical and isotopic analyses of the three youngest pyroclastic products (ca. 86ky) belonging to the Sabatini Volcanic District (Roman Province, central Italy). By means of thermometers, hygrometers and oxygen barometers, we have estimated that the crystallization temperature of magma progressively decreases over time (910–740°C), whereas the amount ...

Experimental evaluation of reservoir quality in Mesozoic formations of the Perth Basin (Western Australia) by using a laboratory low field Nuclear Magnetic Resonance
Accurate porosity and permeability evaluation of rock formations is critical to estimate the quality and resource potential of a reservoir. In addition to directly measure the porosity and pore size distribution, low field Nuclear Magnetic Resonance (NMR) is able to measure the effective porosity and estimate the in-situ formation permeability, though its robustness is arguable and requires cal...
Facies, provenance and paleoclimate interpretation using spectral gamma logs: Application to the Lower Cretaceous of the Scotian Basin
Spectral gamma logging has been useful in some settings for correlation of wells, for identification of sediment facies, and for interpretation of hinterland paleoclimate. We have taken advantage of the hundreds of geochemical analyses of sandstones and shales from conventional core that are available from the Scotian Basin to test the relationship of the elements K, U and Th measured by spectr...
Numerical modeling of slope flows entraining bottom material
Entrainment of bottom material has a substantial influence on the dynamics of slope flows such as snow avalanches and debris flows, and should therefore be taken into account by mathematical models. An approach based on the assumption that the entrainment takes place when the bed shear stress is equal to the shear strength of the bottom material was proposed by . In this paper, this approach is...
Carbonate platform-margins and reefs distribution using 2-D seismic analysis, Central Tunisia
The seismic characterization of sedimentary facies in a carbonate platform, comprising different types of reefs constructions, is based using two-dimensional (2-D) seismic and borehole data. Reefs of the Aptian Serdj carbonates are shown as mounds of strong chaotic amplitudes that have a high-amplitude continuous reflection at the top. They are sealed by Albian marl and claystone deposits chara...