Mineral Resource Estimation: Mike Armitage (22.10.18) скачать в хорошем качестве

Mineral Resource Estimation: Mike Armitage (22.10.18)

A Career in Resource Estimation and Reporting: Thirty Years of Hurt Never Stopped me Kriging Corporate Consultant SRK Consulting (UK) Ltd The techniques commonly used to model the geometry and geological setting of mineral deposits and the spatial variations in the grade/quality of these, and the reporting standards used to present this information in a format that conveys the potential of the deposit to be mined and also the confidence in this potential, have changed significantly over the last 30 years. In 1988, there was generally less time pressure and therefore more time for geological interpretation. There was also less concern with regards integrity of data (BreEx had not happened) and therefore less emphasis on of the quality of exploration data. The computer software available for geological modelling and geostatistical analysis was in its infancy and hard copy geological sections and plans were the start point for most deposit models. Inverse distance interpolation and polygonal analyses were the norm for modelling spatial variations in grade (particularly on operating mines) not least because computers themselves were much less powerful and less freely available. In addition, there were no internationally accepted resource reporting codes and so the terminology used to report the resulting estimates varied from report to report (the first JORC Code was produced in 1989) and was rarely explained. In 2018, the tools now readily available to the resource geologist are much more powerful than those available in the late 1988 and internationally accepted reporting codes have come into being which have broadly standardised reporting. All of this has made it easier to generate and compare estimates more confidently than was possible at that time. There have however been associated challenges and problems which have arisen as a result of these advances. Notably there is now much more time pressure and so less time available for gaining geological understanding and incorporating this into the estimation process and less understanding of the theory behind the techniques being used. This presentation presents a personal view of the changes in resource estimation and reporting over the last 30 years and asks the question whether or not resources estimates produced in 2018 are better than those produced in 1988.