2.2. Case Study Using Geoscience BC Search II Data¶
We’ve now got an idea of how some common ‘geological’ features look in magnetic data, and have been introduced to a variety of tools to help us analyze these features. Now, let’s take a look at some real magnetic data, and apply the same geophysical analysis tools that we applied to the synthetic data from our simple 3D geology scenario.
For this case study, we use magnetic data from Geoscience BC’s Search Phase II project. The Search Phase II magnetic gradient and radiometric survey was flown in 2016, covering an area of 24,000 km2 in west-central British Columbia where several producing and past-producing copper and molybdenum mines are located. East-west oriented flight lines were spaced 250 m apart. This was a draped survey with a flight height of 80 m. Below is an image of the residual magnetic field.
In dealing with ‘real’ data, there are some additional data preparation considerations that may need to be addressed before proceeding to data analysis and interpretation. Data cropping (to a specific area of interest), downsampling (to reduce the number of data), and gridding may need to be done. For this example we use existing gridded data making it easy to jump to visualization and interpretation. We do provide some tools in our Toolkit gallery in Section 3 to help users do additional data preparation if required.
The links below will redirect you to Jupyter notebooks for exploring the Geophysical Toolkit applications as applied to the Geoscience BC Search II magnetic data.
Search II data case study notebooks¶
2.2.1. Magnetic data visualization
This notebook applies sunshading and image enhancements previously introduced in the synthetic modelling section to a subset of the Search Phase II magnetic data set.
2.2.2. 2D magnetic data filters
In this notebook, a subset of magnetic data from the Search Phase II dataset is processed using the suite of 2D magnetic filters presented in the synthetic model case study.
2.2.3. Edge detection
The edge-detection technique previously applied to the magnetic data generated from the our synthetic 3D geologic model, is applied here to a subset of the Search Phase II magnetic data.
2.2.4. Depth to source
We choose a magnetic anomaly within the Search Phase II magnetic dataset and apply two different depth to source methods to assess the depth to the top of the magnetic body.