LØSMASSEMEKTIGHET

This report presents geophysical interpretation results of gravity data as part of a project entitled KARMA-3D. The main goal of the project is to perform three dimensional mapping characterization of Quaternary sediments in order to make the results more comprehensible to non geoscientists such as state officials and engineers. In this sense, gravity prospecting is one of the best techniques to construct density modeling and calculate sediment depths to bedrock due to its low cost compared to other methods and the fact that it can be easily implemented in urban areas. This is exactly the case with our study area which is situated in Orkdal municipality along the river Orkla and represents one of the most populated areas in Sør-Trøndelag county.

This report presents geophysical interpretation results of gravity data as part of a project entitled ORMEL. The main objective of the project is to discern the amount of groundwater, and hence energy, that can be withdrawn from the major sand and gravel sediments in Melhus. The object for this study was depth to bedrock and bedrock morphology. The gravity method is one of the best techniques when sediment thickness estimation is required due to its low cost compared to other methods and the fact that it can be easily implemented in urban areas. This is exactly the case with our study area which is surrounding Melhus city center along the river Gaula.
The gravity survey contains 175 gravity stations with 133 of them positioned along 5 profiles with normally 100 m spacing between each station. The other 42 gravity stations are regional measurements mainly located on bedrock exposures found outside the sediment region. After the acquisition phase, the data has been transformed into Bouguer anomalies and the regional trend which is characterized by an increase in the field towards the southeast has been removed. The sediments in the valley are causing local anomaly lows along the measured profiles with a maximum of 8 mGal.

This report presents geophysical interpretation of gravity data as part of a project whose main objective is to supplement the mapping of Quaternary geology at Stryn. This is achieved through the extraction of depth to bedrock information with the use of gravity data which in turn yields soil thickness and bedrock morphology maps. The gravity method is one of the best techniques when large sediment thickness estimation is required due to its low cost compared to other methods and it can be easily implemented in both rural and urban areas. Our study area is just east of the town of Stryn and farther up the Stryneelva valley.