An earthquake of Mw 5.1 occurred on March 14, 2005, in the seismically active Koyna–Warna region in western India, the site known for the largest reservoir triggered seismicity (RTS) in the world. For more than four decades, earthquakes with M 4.0 have occurred in this region at regular intervals. Impoundment of reservoirs and changes in lake levels can trigger earthquakes by two processes of stress modifications, namely direct loading effect of the reservoir and diffusion through various faults and fractures. In this paper we analysed the reservoir water level data at Koyna and Warna reservoirs prior to the occurrence of the March 14, 2005 earthquake, to explain the dominant mechanism behind its occurrence and its correlation with the observed coseismic changes. We conclude that the diffusion process, not the reservoir load effect, is the dominating mechanism triggering earthquakes in the region. The coseismic changes in deep well water levels sensitive to earth tides are found to be to the order of 1–12 cm. 相似文献
Natural Hazards - Since the initial collision at 55 Ma, rocks of the Indian crust below the Himalayas have undergone modification chemically and compositionally due to the ongoing... 相似文献
Geotechnical and Geological Engineering - Most of the published research on goaf-hole failures are performed using 2D numerical analyses. However, 2D analyses of the goaf-hole failure mechanism,... 相似文献
Global warming with the burgeoning anthropogenic greenhouse gas (GHG) emissions (400 parts per million from 280 ppm CO2 emissions of pre-industrial era) has altered climate, eroding the ecosystem productivity and sustenance of water, affecting the livelihood of people. The anthropogenic activities such as burning fossil fuel, power generation, agriculture, industry, polluting water bodies and urban activities are responsible for increasing GHG footprint of which 72% constitute CO2. GHG footprint needs to be in balance with sequestration of carbon to sustain ecosystem functions. Forests are the major carbon sinks (about 45%) that aid in mitigating global warming. The current research focusses on the carbon budgeting through quantification of emissions and sinks in the forest ecosystems and changes in climatic conditions of Western Ghats. This would help in evolving appropriate mitigation strategies toward sustainable management of forests and mitigate impacts of global warming. The land-use land-cover (LULC) dynamics are the prime driver of climate change due to the loss of carbon sequestration potential as well as emissions. The Western Ghats are one among 36 global biodiversity hotspots and forests in this region sequester atmospheric carbon, which aid in moderating the global climate and sustaining water to ensure water and food security in the peninsular India. Assessment of LULC dynamics using temporal remote sensing data shows the decline of evergreen forest by 5% with an increase in agriculture, plantations and built-up area. The interior or intact forests have declined by 10%, and they are now confined to protected areas. The simulation of likely changes indicates that the region will have only 10% evergreen cover and 17% agriculture, 40% plantations and 5% built-up. Quantification of carbon reveals that the WG forest ecosystem holds 1.23 MGg (million gigagrams or Gt) in vegetation and soils. The annual incremental carbon is about 37,507.3 Gg, (or 37.5 million tons, Mt) and the highest in the forests of Karnataka part of WG. Simulation of the likely changes in carbon content indicates the loss of 0.23 MGg (2018–2031) carbon sequestration potential under business as usual scenario. The conservation scenario depicts an increase in carbon sequestration potential of WG forests with the protection. Sequestered carbon in WG is about INR 100 billion ($1.4 billion) at carbon trading of INR 2142 ($30) per tonne. Large-scale land-cover changes leading to deforestation has contributed to an increase in mean temperature by 0.5°C and decline in rainy days, which necessitates evolving prudent landscape management strategies involving all stakeholders for conservation of ecologically fragile WG. This will enhance the ability of forests to sequester atmospheric carbon and climate moderation, with the sustenance of ecosystem goods and services.
This study presents the results of a field survey that focused on the views of Tasmanian abalone fishery stakeholders (commercial and non-commercial divers, processor, enforcement agency and management) with regards to non-compliance in the abalone fishery. The primary data was collected through 22 face-to-face interviews with stakeholders and the Wilcoxon's signed-rank test was used to determine if significant differences existed between the means of responses from primary and secondary stakeholders. It was found that there is no significant difference in mean responses of primary and secondary stakeholders in regard to the factors that have the potential in influencing the non-compliance in the fishery. The similarity of views between the regulators and resource users on the source and nature of non-compliance in the fishery would form the basis for improved compliance strategies. 相似文献
Earthquakes cause a variety of hydrological phenomena, including changes in the ground water levels in bore wells. The Koyna
region in the peninsular shield of India, hitherto considered stable in terms of seismic activity, has been active since 1967.
More recently, the earthquakes have been localized to the newly impounded Warna reservoir, which is located south of Koyna,
where a burst of seismicity occurred in 1993. The region continues to remain seismically active even after four decades. Twenty-one
bore wells were drilled around the seismic source volume in the region to observe water level changes resulting from earthquake
phenomena. Our studies have shown coseismic anomalous water level changes to be associated with the moderate earthquakes of
April 25, 1997 and February 11, 1998. Our results show that changes in the ground water level in bore wells are correlated
with micro-earthquake activity, both preceding and following moderately sized earthquakes. The results have implications in
enhancing our understanding of earthquake mechanisms. 相似文献
The Dharwar craton, Cuddapah basin and the Godavari graben characterise three diverse geological and tectonic settings in
the peninsular shield of India. Owing to their contiguous proximity, they offer a unique opportunity to document differences,
if any, in their seismic wave attenuation characteristics that might have a bearing on the seismogenic nature of the crust
in a craton, basin and a rift-like graben structure. An attempt is made here to bring out these differences using constraints
from coda-Q. We considered local earthquakes with epicentral distances ranging from␣14 to 150 km recorded at the digital broadband stations
at Dharwar (DHD), Cuddapah (CUD) and Kothagudem (KGD) regions to derive the frequency-dependent coda-Q relations. Using the single scattering method, we obtained the frequency-dependent QC relationship (QC = Q0fn)for each of the three geological units separately: DHD: QC = (730.62 ± 0.09)f(0.54 ± 0.01); CUD: QC = (535.06 ± 0.13)f(0.59 ± 0.01) and KGD: QC = (150.56 ± 0.08)f(0.91 ± 0.01). The QC values obtained for all the three sub-regions show moderate to strong frequency dependence and essentially reflect the level
of crustal heterogeneities to varying degrees. 相似文献
In April 2013, a 7.0 Mw earthquake struck along the Longmen Shan fault in the city of Ya’an, Sichuan Province, China, causing serious damage. The invaluable contributions of the non-governmental organizations (NGOs) in dealing with this disaster highlighted the significance of government–NGO relationships in post-disaster reconstruction and the effect this has on the efficiency and quality of post-disaster reconstruction. This paper examines government–NGO relationships (GNR) in the post-Lushan earthquake period as a multi-stakeholder collaborative problem based on organizational lifecycle perspectives through the birth, growth, stability, and saturation stages. Two-year field research was conducted in the affected areas which identified the GNR as a bridged government–NGO relationship (BGNR) during the reconstruction period, with the Ya’an service center acting as the bridging organization. The BGNR’s experience was compared to the previous Wenchuan earthquake, and the general BGNR post-disaster reconstruction situation is discussed on two dimensions: mutuality and organizational identity. 相似文献
The genetic diversity and variation of three pseudo‐species of the commercially important Indian conch Turbinella pyrum from the southeast coast of India were studied. A total of 88 individuals was genotyped at 12 loci and differences in the genetic diversity among genetic groups were correlated with known population histories. The study identified 535 alleles and all the studied loci were highly polymorphic. The number of alleles ranged between four and 29 with a global mean of 14.861. The global means of the observed and expected heterozygosities were 0.774 and 0.891, respectively. The estimated within‐population inbreeding value (FIS = 0.131) indicated a shortfall of heterozygosity in the populations. An analysis of molecular variance showed that 5% of the total variation was due to differences between genetic groups. The Bayesian approach revealed strong distinctiveness in the three genetic groups studied. Overall microsatellite analysis revealed less genetic diversity in all studied genetic groups and significant genetic variation among the three pseudo‐species. The study highlights the significant distinctiveness of the pseudo‐species of T. pyrum and the need for appropriate conservation efforts in order to prevent further losses of their genetic diversity. 相似文献
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