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F.H. Chamalaun S.N. Prasad F.E.M. Lilley B.J. Srivastava B.P. Singh B.R. Arora 《Tectonophysics》1987,140(2-4):247-255
The geomagnetic variation data from the 1979 Indian array experiment have been reanalyzed and reexamined using the hypothetical event analysis technique. The contour map of the |Z/H ratio replicates distinctive anomaly in northwest India previously delineated in maps of the Fourier coefficients. The anomaly reveals the presence of a significant conductor under the Ganga basin. The contour map has been used to derive a response profile perpendicular to the strike of the anomaly, for comparison with 2-D numerical models. An excellent fit was found for a conductor at a depth of 32 km, with a width of 110 km and a conductivity contrast of 1000. This result places the conductor deep within the lithosphere. In the absence of supporting data the origin of the conductor is difficult to resolve. However, it is thought to be related to pressure-released partial melting, caused by fracturing of the Indian crust during the collision of India with Asia. 相似文献
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The relative toxicities of seven non insecticidal chemicals to Mesocyclops leuckarti were tested. The relative toxicity of each chemical is given as under: Chlorine water > Potassium permanganate > Cetavlon > Quicklime > Common alum > Savlon > Sodium bicarbonate. 相似文献
44.
The Precambrian phosphorites of Bijawar Group of rocks show characteristics of a epicontinental sea with restricted and very shallow marine environment of formation along some shoals, which existed during the iron-rich Precambrian times. These phosphorite deposits located in the Hirapur-Bassia areas show extensive leaching of carbonate and phosphate minerals during episodes of weathering. X-ray diffraction studies indicated that carbonate-flourapatite is the major apatitic phase in these phosphorites while crandallite developed on the surface outcrops. There is a general tendency for the depletion of CO2 in these apatites leading to formation of flourapatite. This CO2 is an indicator of hidden weathering in the rocks. Major and trace element determinations of phosphorite have been used to indicate various correlation factors responsible for the concentration of elements in these Precambrian leached phosphorites.The paper is a contribution to the aims and objectives of IGCP Project 156The paper is dedicated to Prof. Dr. R. C. Misra, who as a teacher and guide had been a source of inspiration to the senior author for the last two decades 相似文献
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AnnGIS: Integration of GIS and a Continuous Simulation Model for Non-Point Source Pollution Assessment 总被引:1,自引:0,他引:1
Puneet Srivastava Rick L. Day Paul D. Robillard & James M. Hamlett 《Transactions in GIS》2001,5(3):221-234
Non-Point Source (NPS) models and monitoring data are often used to evaluate management practices and develop NPS pollution control plans. Application of a dynamic NPS model requires efficient input data acquisition, storage, organization, reduction, and analysis accompanied by manipulation, interpretation, reporting, and display of model outputs. A Geographic Information System (GIS) helps extract, store, and organize input data as well as manipulate and display model outputs. This paper illustrates the development of an integrated GIS system for a continuous simulation, pollutant-loading model, AnnAGNPS ( Ann ualized AG ricultural N on- P oint S ource Pollution). The integrated system, called AnnGIS, was developed using the ArcView GIS and related program extensions. Using AnnGIS, modeling studies and management plans can be efficiently and easily developed. AnnGIS helps store, organize, and manipulate spatial and tabular data, extract spatial input parameters, develop analysis scenarios, and visualize input and output data in spatial, tabular, and graphical forms. AnnGIS is generic in nature (not limited to a particular geographic location) and can be successfully used in regions for which AnnAGNPS is designed. AnnGIS's powerful graphical user interface and reference data sets facilitate efficient and informed decision-making concerning agricultural non-point pollution control and management. 相似文献
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Summary The spectra of Matsushiro micro-earthquakes were studied using a spectrum analyser and discussed in relation to their magnitude and the epicentral distance. It was found that the spectra of seismic waves by Matsushiro micro-earthquakes did not depend upon the epicentral distance since the sonagrams showed a peak around 5 cps at Matsushiro as well as Suzaka. The spectrum also failed to show any distinct peak for micro-earthquakes of magnitude lower than 1.0 due to the decrease of signal to noise ratio. 相似文献
48.
Innes D.E. Inhester B. Srivastava N. Brekke P. Harrison R.A. Matthews S.A. Noëns J.C. Schmieder B. Thompson B.J. 《Solar physics》1999,186(1-2):337-361
The structure and dynamics of the initial phases of a coronal mass ejection (CME) seen in soft X-ray, extreme ultraviolet and optical emission are described. The event occurred on the SW limb of the Sun in active region AR 8026 on 9 April 1997. Just prior to the CME there was a class C1.5 flare. Images taken with the Extreme Ultraviolet Imaging Telescope (EIT) reveal the emergence of a candle-flame shaped extreme ultraviolet (EUV) cavity at the time of the flare. Yohkoh images, taken about 15 min later, show that this cavity is filled with hot X-ray emitting gas. It is most likely that this is the site of the flare. Almost simultaneous to the flare, an H surge or small filament eruption occurs about 50 arc sec northwards along the limb from the EUV cavity. At both the site of the core of the hot, EUV cavity and the filament ejection are X-ray jets. These jets seem to be connected by hot loops near their bases. Both jets disappear within a few minutes of one another.Clear evidence of the CME first appeared in the Large Angle Spectrometric Coronagraph (LASCO) and EIT images 40 min after the flare and onset of the filament ejection. It seems to come from a region between the two X-ray jets. This leads to the speculation that magnetic field reconnection near one footpoint of a loop system triggers reconnection near its other footpoint. The loop system is destabilized and ultimately gives rise to the CME. This possibility is supported by magnetic field and H images taken when the active region was at disk center which show that the active region had a double bipole structure with dark H filaments between the bipoles. 相似文献
49.
U, B, andV observations of RZ Eri have been reported. Colours of comparison stars BD-10°994, BD-10°996 and of the variable RZ Eri have been presented. The observations of RZ Eri do not indicate the distortion wave in the light curve beyond observational scatter. 相似文献
50.