Mining MMI Orientation Surveys
Mobile Metal Ions (MMI) is a proven geochemical survey technique used to accurately locate deep ore deposits.
MMI orientation surveys are valuable in all exploration settings but are especially recommended in areas of where the unconsolidated material is known to be transported from its source area.
Before a full MMI™ exploration project is undertaken, it is important to test the application of the MMI technique to ensure optimal sampling and test results. A properly designed Orientation Survey is usually done at a small scale over a known area of mineralisation to ensure strong signals. Such surveys will prove the applicability of MMI in a given area and will help determine optimum survey parameters, especially sampling depth.
An MMI Orientation Survey consists of a single transect over a known target, with dense site spacing. Multiple samples are collected from each sample pit. The primary reasons for performing this survey are to:
- Determine a site spacing that is sufficiently dense to identify mineralisation
- Identify which elements characterise the mineralised zone
- Establish the appropriate depth below live organic material at which to collect samples
- Determine whether to do the complete MMI suite
- Establish the appropriate elements to use in a reduced MMI–M package, or if the complete MMI package is needed
The following guidelines should be followed to ensure the proper design of your Orientation Survey:
- The samples should be collected at 15 – 25m intervals and the spacing reduced to less than 15 m when directly over the mineralised target zone
- Samples should be taken over the target’s centre and beyond to include the hanging wall and the footwall of the mineralisation or edges of the mineralised zone
- Extend the sampling at least 150 m beyond the edges of the target mineralised zone to capture the background MMI levels
- 25 sampling sites are required and at least 3 must be over the target to ensure sufficient coverage
- Each site must cross sect the soil profile by at least 40 cm
The final, optimal distance between sample sites will be dictated by the type and size of the mineral deposit target. For example, fault-hosted gold deposits will likely have closer sample spacing than a porphyry copper deposit.
Proper collection procedures are vital to the success of an MMI Orientation Survey. SGS experts will guide you through our specific protocols, which are based on years of experience and research, to ensure proper sample collection.
An MMI Orientation Survey ensures your full MMI geochemical survey is properly designed and thus maximise its chance for success. MMI Orientation Survey data is reported in parts per billion and so proper methodology and attention to cleanliness is important to ensure accurate, repeatable data. When done properly, it will help to ensure the applicability and optimisation of your full SGS MMI survey.
SGS represents the global benchmark for accuracy and integrity in analytical procedures. We will work with you to ensure your survey is performed to the level of excellence required to achieve optimum MMI results. Call us today to discover more.