Porphyry indicator minerals and their mineral chemistry as vectoring and fertility tools

Investigating the diamond potential of southern West Greenland

Geological Survey of Denmark and Greenland Bulletin ◽

10.34194/geusb.v4.4788 ◽

2004 ◽

Vol 4 ◽

pp. 69-72 ◽

Cited By ~ 2

Author(s):

Sven Monrad Jensen ◽

Karsten Secher

Keyword(s):

Structural Control ◽

Mineral Chemistry ◽

Mantle Xenoliths ◽

Comprehensive Overview ◽

West Greenland ◽

Large Samples ◽

Indicator Mineral ◽

The Government ◽

Indicator Minerals ◽

Diamond Potential

Southern West Greenland hosts a province of ultramafic alkaline rocks, including swarms of dykes traditionally described as kimberlites and lamproites (Larsen 1991; Jensen et al. 2002). Since the mid-1990s, commercial diamond exploration has been focused on the Sarfartoq region and the region south-east of Maniitsoq (Fig. 1), and has resulted in numerous reports of diamond-favourable indicator minerals from till sampling, finds of kimberlitic dykes, and recovery of diamonds from kimberlitic rocks. A new digital compilation of company data released from confidential status (Jensen et al. 2003a) presents a comprehensive overview of exploration activities and results that have emerged since the Survey’s first compilation of occurrences of kimberlitic and related rocks (Larsen 1991). The new compilation in a GIS (geographic information system) environment allows for refined assessment of the distribution, structural control and possible spatial and petrogenetic relationships that characterise the kimberlitic occurrences. In 2003, the Geological Survey of Denmark and Greenland (GEUS) and the Government of Greenland’s Bureau of Minerals and Petroleum (BMP) went further than has been customary in investigating the economic potential of specific sites. Four areas were temporarily closed to application for exploration licences, pending sampling and testing for diamond content of large samples of more than one tonne each from significant kimberlitic occurrences. Additional characterisation and research initiated on these and other occurrences include magnetic mapping, detailed petrography and studies of mantle xenoliths, as well as indicator mineral chemistry. An extensive programme to determine the ages of kimberlitic and related rocks was also initiated in 2003.

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Kimberlite indicator mineral chemistry of the Bucke and Gravel kimberlites and associated indicator minerals in till, Lake Timiskaming, Ontario

10.4095/289599 ◽

2012 ◽

Cited By ~ 1

Author(s):

M B McClenaghan ◽

I M Kjarsgaard ◽

B A Kjarsgaard

Keyword(s):

Mineral Chemistry ◽

Indicator Mineral ◽

Indicator Minerals

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Current Techniques and Applications of Mineral Chemistry to Mineral Exploration; Examples from Glaciated Terrain: A Review

Minerals ◽

10.3390/min12010059 ◽

2021 ◽

Vol 12 (1) ◽

pp. 59

Author(s):

Daniel Layton-Matthews ◽

M. Beth McClenaghan

Keyword(s):

Mineral Exploration ◽

Mineral Chemistry ◽

Heavy Mineral ◽

Optical Identification ◽

Glacial Sediments ◽

Volcanogenic Massive Sulfides ◽

Kimberlite Indicator Minerals ◽

Indicator Mineral ◽

Automated Mineralogy ◽

Indicator Minerals

This paper provides a summary of traditional, current, and developing exploration techniques using indicator minerals derived from glacial sediments, with a focus on Canadian case studies. The 0.25 to 2.0 mm fraction of heavy mineral concentrates (HMC) from surficial sediments is typically used for indicator mineral surveys, with the finer (0.25–0.50 mm) fraction used as the default grain size for heavy mineral concentrate studies due to the ease of concentration and separation and subsequent mineralogical identification. Similarly, commonly used indicator minerals (e.g., Kimberlite Indicator Minerals—KIMs) are well known because of ease of optical identification and their ability to survive glacial transport. Herein, we review the last 15 years of the rapidly growing application of Automated Mineralogy (e.g., MLA, QEMSCAN, TIMA, etc) to indicator mineral studies of several ore deposit types, including Ni-Cu-PGE, Volcanogenic Massive Sulfides, and a variety of porphyry systems and glacial sediments down ice of these deposits. These studies have expanded the indicator mineral species that can be applied to mineral exploration and decreased the size of the grains examined down to ~10 microns. Chemical and isotopic fertility indexes developed for bedrock can now be applied to indicator mineral grains in glacial sediments and these methods will influence the next generation of indicator mineral studies.

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