زرياب الترابي مشرف قسم التعدين


عدد المساهمات : 535 تاريخ التسجيل : 12/10/2009 العمر : 38 الموقع : الترابي
 | موضوع: Standard Operating Procedures 29th مايو 2015, 5:18 am | |
| EXPLORATION: STREAM SEDIMENT SAMPLING PROCEDURE The aim of this procedure is to ensure constant, accurate and precise method to collect stream sediment sample from the field.
Equipment: Compass, GPS, batteries, sample bags, labels, metallic tags, staplers, brush, shovel, pickaxe; markers; rope of 50m length, sieves (2mm and 125 micrometers) and flexistack bottom and top rings.
Support document: Sample map position superimposed to topography and hydrographic network, sample sheet program (sample number and position), sampling sheet description and notebook.
Human resource: Team of 4 workers including driver and geologist.
Stream sediment location to be sampled:
- Ensure that workers who are involved in the collection of samples don’t wear jewelry of various Metal
- Avoid taking samples along major streams,
- Focus on meander sedimentation zones (MSZ) of small streams located downstream of the watershed and outside of major stream materials deposited during flood periods,
- Ensure the sample is collected in the stream even if the position indicate with GPS could be outside of the drainage channel. In this case move the position of this latter to coincide with the real position in the field.
Stream sediment fraction to be sampled and analyzed: It is hard know which size fraction will work best without having done some orientation work. But we do know though that the previous work done in Managem tenements that fraction -125 micrometers work well.
We should analyze all samples for multi-elements as well as Au, and recover all pulps.
The assay method should be aqua regia extracted into DIBK, AAS finish - Au Detection Limit 2ppb.
Sampling method:
- Sampling point position (SPP) is defined with GPS.
- The geologist has to seek the MSZ position and record the new position in case.
- Remove the recent sand layer if exists and start sampling around 300g of soil horizon sieved to 125 micrometers. One worker dig the hole, another remove the material from the hole and prepare the sample label, sample bag and sieve the material in order to collect the adequate quantity. All these operations should be realized with the presence of a geologist.
- In the sample map position, the position of the sample collected should be colored, stream, rock chip of outcrops, structures when collected. Geologist has to record all the other description elements mentioned in the sampling sheet description.
- Before moving to the next sample point, sieves should be well brushed in order to ovoid contamination.
- In the office, the collect point coordinates should be saved in the computer and projected in 2D plan in order to control if there is any position error.
- Stream sediment samples should be submit periodically to the laboratory with the following sequence in each 50 sample benches:
o Sample 1 = Blank, o Sample 21 = Duplicate, o Sample 41 = Standard (ppb)
| |
|