from the announcement
"a substantial program of air-core drilling has commenced" :
Air-core drilling is actually an Western Australian invention and is preferred over rotary air blast (RAB) drilling, as it tends to provide more representative, or more accurate samples. So it is used when safe and clean removal of sample material is paramount with less chance of cross-contamination. It uses a three-bladed steel or tungsten drill bit with a hollow drill rod to penetrate the weathered layer of loose soil and rock fragments.
Air-core drilling is relatively inexpensive and is often used in first pass exploration drill programs. Air-core drilling is limited to depths of 50-60 metres and is drilled using a smaller rig known as an Air-core rig.
Once drilling is complete, compressed air is injected into the space between the inner tube and drill rod’s inner wall to flush the cuttings to the surface. This makes samples from air-core drilling less prone to contamination, though it is generally slower and more costly than RAB. Aircore is also unable to cut through fresh rock.
"Deeper Reverse Circulation (RC) drilling will be planned once results from the air-core drilling and ground EM are received and processed."Moving on to the big guns, reverse circulation, or RC drilling as it is more commonly known, is a popular technique for mineral exploration.Like RAB, RC drilling uses a piston-driven “hammer” to drive a tungsten-steel bit into the rock, though the use of larger rigs and machinery allows holes to be drilled much deeper (RC drill rigs with their considerably larger equipment can typically reach depths of 300 to 600m, with up to 200/300 metres per day).It also has similarities with aircore drilling in its use of compressed air to drive the dry rock chips up the inner tube.Another Australian invention, RC drilling is ideally suited for exploration, as it delivers contaminant-free samples, which means that results can be delivered to clients faster.
"In addition to the air -core drilling, in-fill and first-pass auger sampling will be on-going, which is expected to provide further targets for drill testing."Auger drilling is the baby of the different types of drilling.It is done by rotating a helical screw into the ground with the earth being lifted up the borehole by the blade of the screw.
They range in size from small hand-held units to somewhat larger ones mounted on small vehicles. Auger drilling can only really be used where the ground is soft but it is both cheap and fast, making it suitable for its main use as an initial geochemical reconnaissance technique.Translation, it is often used to find good spots to stick other, bigger drill rigs on.
"Ground electro-magnetic (EM) surveys are also scheduled to commence before Christmas to follow up anomalies defined by the airborne EM (AEM) survey flown in August 2020."As explained previously ground electro-magnetic EM is more sensitive and with that more accurate than the earlier airborne electro-magnetic survey and so are used to zoom in on the eventual target.
I hope the above clears up what has been going on at the Moora project and will continue "next year".
I'm still hoping that some announcement re a drilling update could make it to the market, because the SP could do with a little support as we speak.
(20min delay)