agy not just about burundi, page-4

Zed....

"....A MASSIVE sulphide source...."



I noticed that you emphasised the word 'massive'....the term massive sulphides is not meant to infer that there is a massive resource down there, but rather it is a term used to describe a type of geological formation.


-------------------------------------------


VMS deposits may be either bowl-shaped or mound-shaped. The bowl-shaped formations formed due to venting of hydrothermal solutions into submarine depressions - in many cases, this type of deposit can be confused with sedimentary exhalative deposits. The mound-shaped deposits formed in a way similar to that of modern massive sulfide deposits - via production of a hydrothermal mound formed by successive black smoker chimneys.

VMS deposits have an ideal form of a conical area of highly altered volcanic or volcanolithic sedimentary rock within the feeder zone, which is called the stockwork zone, overlain by a mound of massive exhalites, and flanked by stratiform exhalative sulfides known as the apron.

The stockwork zone is generally full of vein hosted sulfides, adularia, quartz, carbonates, barite and kaolinite in an interlocking, brecciated tangle which often shows colloform textures and evidence of boiling of the hydrothermal fluids.

The mound zone is a chaotic breccia of manganese, pyrite, hematite, barite, ore minerals, and jaspilite, usually shot through with veins of sulfide and small pods and lenses. This is in turn overlain by massive sulfides, up to several metres thick and several hundred metres in diameter.

The apron zone is generally more oxidised, with stratiform, laminated sulfidic sediments, similar to SEDEX ores, and is generally manganese, barium and hematite rich, with cherts, jaspers and chemical sediments common.

The mineralogy of VMS deposits consists of over 90% iron sulfide, mainly in the form of pyrite, with chalcopyrite, sphalerite and galena also being major constituents. Magnetite is present in minor amounts; as magnetite content increases, the ores grade into massive oxide deposits. The gangue (the uneconomic waste material) is mainly quartz and pyrite or pyrrhotite. Due to the high density of the deposits some have marked gravity anomalies (Neves-Corvo, Portugal) which is of use in exploration.

-----------------------------------------------------


I suspect what you are really trying to do here is discover what this mystery left-field announcement might be....it has nothing to do with nickel whatsoever.

Cheers.