The use of potential field data in revealing the basement structure in sub-basaltic settings: an example from the Møre margin, offshore Norway     

R.F. Reynisson  J. Ebbing  J.R. Skilbrei 《Geophysical Prospecting》2009,57(4):753-771

This study investigates the utility of the potential fields (gravity and magnetics) in volcanic settings as observed on the Møre margin. Synthetic models are used to investigate the effect of volcanics on the gravity and magnetic fields. The focus is on detecting sub-basaltic basement structures. The methods applied to the models are Euler deconvolution on magnetic data, gravity gradients and integrated 3D gravity and magnetic forward modelling. The same methods are used on the Møre margin and the results compared to the synthetic models. The Euler deconvolution on the magnetic signal does provide limited depth solutions in the volcanic environment and the use of different observation levels does not enhance the results. Forward gravity and magnetic models provide a valuable tool to estimate both the basalt and sub-basaltic sedimentary thickness but are limited by the ambiguity inherent in potential field methods. The use of gravity gradients significantly decreases the available model solutions and provides boundary detection even in sub-basaltic settings.  相似文献   

On the use of the autocorrelation method for estimating the depth to the magnetic basement     

Jan Reidar Skilbrei  Ola Kihle 《Pure and Applied Geophysics》1992,138(3):501-506

The depth to the top of magnetic dykes can be estimated from total field aeromagnetic data using the relation between the depth to magnetic sources and the autocorrelation function of magnetic data. By using synthetic anomalies we show that in the ideal case, depth can be determined to an accuracy of 10% or better, when the anomaly sources are two-dimensional dykes. However, the estimated depths depend on the width of the dykes. The estimated depth is about 0.6 times the actual depth to the top of thin dykes, and around the true depth for thick dykes having width-to-depth ratio around 3. The depth is considerably overestimated for very thick dykes (e.g., contacts, which is a special case of the thick dyke). Thus, the autocorrelation method requires that the width-to-depth ratio of the dyke is estimated independently to correctly estimate the depths. Alternatively, it must be assumed that the width-to-depth ratio for the two-dimensional source body is between 1.5 and 4.  相似文献   

The use of catch statistics to monitor the abundance of escaped farmed Atlantic salmon and rainbow trout in the sea     

Skilbrei  Ove T.; Wennevik  Vidar 《ICES Journal of Marine Science》2006,63(7):1190-1200

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Vertical movements of "escaped" farmed Atlantic salmon (Salmo salar L.)--a simulation study in a western Norwegian fjord     

Skilbrei  Ove T.; Holst  Jens Christian; Asplin  Lars; Holm  Marianne 《ICES Journal of Marine Science》2009,66(2):278-288

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Survival and growth of sea-ranched Atlantic salmon, Salmo salar L., treated against sea lice before release     

Skilbrei  Ove T.; Wennevik  Vidar 《ICES Journal of Marine Science》2006,63(7):1317-1325

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