Bashir Ahmad

Comment on: “Earthquake geology of Kashmir Basin and its implications for future large earthquakes” by Shah (2013); “Kashmir Basin Fault and its tectonic significance in NW Himalaya, Jammu and Kashmir, India” by Shah (2015)

(KBF) without any additional structural, kinematic, geologic or geomorphic data in support. Therefore, this comment aims to clarify the confusions created by Shah (2013, 2015a), and it is in this context; we provide a review of the BF. No active faults/out-of-sequence thrusts/tectonic discontinuities were known north of MBT or MCT in the Kashmir basin, except a few NW–SE suspected fault segments with the collective length of ~45 km along NW Quaternary deposits, mapped from aerial photographs and CORONA satellite images (Nakata et al. 1991), and a south-facing scarp delineated as a possible active fault using Landsat satellite images (Yeats et al. 1992). Subsequent investigations revealed that the southwest-facing scarp (Yeats et al. 1992) is a high-angle thrust fault (reverse) with an average northeast 60° dip and NW–SE strike length of ~40 km (Ahmad 2010; Madden et al. 2010, 2011; Ahmad and Bhat 2012) (Figs. 1, 2, 3). The structure was named as BF because of its exposure on the left bank of Rambiara river (tributary of Jhelum river) at Balapur village (N 33° 75′ E 74° 83′) in Shupiyan district of Jammu and Kashmir state, India (Ahmad 2010; Ahmad and Bhat 2012). With an unknown depth, the BF cuts across (NW–SE) unconsolidated Karewa deposits (Plio-Pleistocene soft sediments), devoid of gouge and breccia; however, rotated gravels at the fault contact have been marked (Ahmad and Bhat 2012). Stratigraphic relations show that the fault has uplifted the Lower Pleistocene Methawoin Member (sand, sandy clay, clay silt and lignite bands) of the Lower Karewa and juxtaposed it to the Middle Pleistocene Shupiyan Member (gravels mostly composed of Panjal Trap fragments of the Upper Karewa (Bhatt 1989). Subsequently, the BF was firmly established by paleoseismic investigation and field data (Madden et al. 2010, 2011; Ahmad et al. 2013; Ahmad 2014). An optically stimulated luminescence (OSL) sample collected from fluvial deposits a few meters above the lower strath gives Comment

Looking for Missing Links in Kashmir: An Update on Nineteenth-Century Seismicity

Nineteenth century Kashmir witnessed military interventions as well as foreign invasions of different ethnic and religious entities. Coups d’etat, coupled with sporadic appearances of epidemics and other natural disasters, were also prevalent. Despite all these upheavals, the influx of various European travelers and their attention to natural phenomena such as earthquakes immensely contributed to knowledge of the earthquake history of this remote pastoral valley. According to the latest issue of the Kashmir seismic catalog, the area has a centuries‐old history of moderate magnitude events (Ahmad etxa0al. , 2009). However, this picture might be incomplete, as suggested by the recent discovery of previously unknown earthquakes that occurred in the nineteenth century. The objective of the present research is to fill the information gaps regarding the occurrences of known earthquakes in the Kashmir Valley and neighboring regions and to identify previously unknown seismic events. As part of this work, six previously unreported earthquakes have been identified, and information on five previously reported earthquakes has been updated. This was achieved by studying historical documents coeval to the events.nnNineteenth‐century Kashmir was seriously affected by several earthquakes, which occurred in 1803, 1819, 1828, 1863, and 1885 (Ahmad etxa0al. , 2009). Several studies on particular events (e.g., 1828 and 1885) have been recently published by Bilham etxa0al. (2010) and Ahmad etxa0al. (2014), respectively. These seismic events are known as having been among the largest in this region in the nineteenth century, as they caused major damage to the natural and built environments. Moreover, in the published historical seismic catalogs of Kashmir (e.g., Iyengar etxa0al. , 1999; Ahmad etxa0al. , 2009), specific seismic information gaps (blank time windows with regard to the occurrences of seismic events) have been evident and only recently filled by Ahmad and Shafi (2014) through the rediscovery of a fair …

Low energy heavy ion detection with the plastic scintillator NE102E

Detection capabilities of low cost plastic scintillation detector NE102E have been explored for slow heavy ions and carbon clusters. The carbon clusters are produced in a graphite hollow cathode based duoplasmatron and the mass analysis performed by a compact E×B velocity filter. The energy of the heavy ion beams of C70+, C60+, C24+, Xe2+, Xe+ and Ar+ is varied between 1 and 10 keV. The experimental data suggests that the scientillation response of NE102E is related to the electronic stopping and after a critical longitudinal range of about 80 A the scintillator’s response becomes linear.

Evolution of clusters in energetic heavy ion bombarded amorphous graphite

A study has been conducted into the mechanisms of evolution of clusters and their subsequent fragmentation under energetic heavy ion bombardment of amorphous graphite. The evolving clusters and their subsequent fragmentation under continuing ion bombardment are revealed by detecting various clusters in the energy spectra of the Direct Recoils emitted as a result of collisions between ions and surface constituents. The successive Direct Recoil spectra reveal that the energetics of Carbon Carbon bond formation as well as any subsequent fragmentation can be related to the processes of energy dissipation in a cylindrical volume of a few Angstrom surrounding the ion path. The dependence of cluster with m carbon atoms formation or its subsequent fragmentation into cluster with m-2 carbon atoms and diatomic carbon C2 is seen to be a function of the ionic stopping powers in this cylindrical volume.

MULTIPLY CHARGED DIRECT RECOIL SPECTRA FROM AR+ AND KR+ BOMBARDED GRAPHITE

Abstract Measurements of the energy spectra of multiply charged positive and negative carbon ions (Cn ±) recoiling from graphite surface under 100 and 150 keV argon and krypton ion bombardment are presented. With the energy spectrometer set at recoil angle of 79.5°, direct recoil (DR) peaks have been observed with singly as well as multiply charged carbon ions Cn ±, where n = 1 to 6. These Cn ± ions have been seen recoiling with the characteristic recoil energy EDR = kE0cos2 θDR, where θDR is the direct recoil angle, k = 4m 1 m 2 (m 1 + m 2 ) 2 , m1 and E0 are projectile mass and energy and m2 is carbon mass. We have observed sharp DR peaks. A collimated projectile beam with divergence ∼ ±0.2° is supplemented with a similar collimation before the energy analyzer to reduce the background of sputtered ions due to scattered projectiles.Measurements of the energy spectra of multiply charged positive and negative carbon ions recoiling from graphite surface under 100 and 150 keV argon and krypton ion bombardment are presented. With the energy spectrometer set at recoil angle of 79.5 degrees, direct recoil (DR) peaks have been observed with singly as well as multiply charged carbon ions , where n = 1 to 6. These monatomic and cluster ions have been observed recoiling with the characteristic recoil energy E(DR) . We have observed sharp DR peaks. A collimated projectile beam with small divergence is supplemented with a similar collimation before the energy analyzer to reduce the background of sputtered ions due to scattered projectiles.

Technetium-99m extraction and transport across tri-n-octylamine-xylene based supported liquid membranes

The nuclear properties of99mTc radionuclide are ideal for organ imaging. Study of the technetium transport across supported liquid membranes has been performed to get data for its separation from other elements. Tri-n-octylamine diluted in xylene was used to constitute the liquid membranes, supported in polypropylene microporous films. Stripping on the product solution side was performed with dilute NaOH solutions. The effect of sulphuric acid, nitric acid and hydrochloric acid in the feed on transport of99mTc as TcO4− ions has been studied. The permeability of the given ions determined from kinetic activity data has been found to be in the order of PH2SO4>PHCl>PHNO3. The flux values have been calculated based on this permeability data. The increase in carrier concentration has shown an increase in flux and permeability values to a given optimum concentration. The increase in temperature has been found to reduce the transport of Tc ions. The optimum conditions for transport of99mTc for the given acid concentration have been determined. Mechanism of Tc ion transport has also been provided based on chemical reactions involved at the membrane interfaces and uptake of Tc ions by the membrane. MoO42− ions do not permeate through membrane under optimum conditions of transport for TcO42− ions from H2SO4 solution.

Transport of99mTc across TBP-kerosene oil supported liquid membranes

Transport of99mTc across tri-n-butylphosphate (TBP) kerosene oil supported liquid membranes (SLM) has been studied under various conditions. Presence of dichromate ions helps avoid activity scavenging effects. Concentration increase of TBP, the complexing carrier used in the present study has a positive effect on flux (J) and permeability (P) of these ions, as up to 2.87M there is an increase in J and P values. HCl concentration in the feed solution increases J and P with their maximum values at 2.5–3.0M HCl in the feed. Above this concentration there is a decrease in flux and permeability of99mTc(VII) ions. The given ions are stripped with LiCl or NaCl solutions but more with NaOH. The optimum conditions of transport of the given ions are 2.5M HCl concentration in the feed, 2.87M TBP concentration in the membrane and 1M NaOH concentration in the strip solution. Equations have been developed to indicate the relation between flux, J, viscosity, ν of TBP in organic membrane phase, temperature, T, [H+], in the aqueous feed solutions and Tc ion concentration in the feed solution. Based on P, the values determined from liquid membrane experiments, the quantitative flux values of Tc(VII) ions were also determined as a function of TBP concentration in the membranes, and HCl and Tc concentration in the feed solution using the given equations. This experimental technique provides quantitative results from trace level activity transfer experiments.

Transition from the C3-dominated discharge to the sooting plasma.

Mass spectrometry and photoemission spectroscopy of a graphite hollow cathode source identify the parameters of the transition from the C3-dominated discharge to the sooting plasma. The transition is a function of the shape and profile of a special cusp magnetic field B(z)(r, theta), the geometry of the source, the discharge current, and pressure. Characteristic atomic and molecular emission lines and bands in the C3 discharge transform into broad bands emitted by the excited soot. We identify four prominent emission bands between 300-400 nm to be the hallmark of the sooting plasma.

A compact, permanent-magnet-based E×B velocity filter for carbon cluster diagnostics

Abstract An E × B velocity filter is described that has been used for the detection and diagnostics of large carbon clusters C m (m≤10 4 ) . The velocity and momentum analyses are compared for our special experimental arrangement. We describe the variability of the resolving power of our compact velocity filter as the main advantage over other comparable mass analysis techniques.An ExB velocity filter is described that has been used for the detection and diagnostics of large carbon clusters Cm (where m is up to ten thousand). The velocity and momentum analyses are compared for our special experimental arrangement. We describe the variability of the resolving power of our compact velocity filter as the main advantage over other comparable mass analysis techniques.

Flood risk assessment of Srinagar city in Jammu and Kashmir, India

Purpose Risk assessment is imperative for disaster risk reduction (DRR). The risk is rooted to various physical, social, economic, demographic, and environmental factors that determine the probable magnitude of loss during an extreme event. By way of bringing a conceptual model into practice, this paper aims to examine the flood risk of the Srinagar city. Design/methodology/approach The ‘risk triangle’ model has been adopted in the present investigation evaluating parameters, reflective of hazard (intensity), exposure (spatial), and vulnerability (sensitivity) using Landsat-8 Operational Land Imager (OLI) scene (2014/09/10), Global Positioning System (GPS), Cartosat-1 Digital Elevation Model (DEM), and socioeconomic and demographic data (Census of India, 2011). We characterize flood hazard intensity on the basis of variability in water depth during a recent event (September-2014 Kashmir Flood); spatial exposure as a function of terrain elevation, and socioeconomic structure and demographic composition of ...