Australia's largest stock trading and investment forum Australia's #1 stock forum

ESS

0.00%

50.0¢ essential metals limited

Ozwtisgold and PIO Reference, page-75

First 75 Last

Share
Profile

Follow
Bigsky

636 Posts.

66

20/11/17

01:18

Post #: 28935953
Share

Originally posted by Blue swims ↑

Yes definitely needs the mafic conglomerate and the MRB capping, but my own take on the rest is a bit different. Take it as you will.
Regionally- 2.8 Ga was about the start of period of intense earthquake / volcanic activity probably tectonic or rising magma derived.
Location- if we're looking at Northern Pilbara evidence is that theyre generally a shallowish lacustrine( lake) environments with an ecosystem.( stromatolites, methotrophs, methogens)
Timing -2.77 Ga is a date where several events/ processes can simultaneously occur . MRB flows , mafic conglomerate,hydrothermal vent alteration, dolerite dykes ( all zircon dated).
Phrenomagmatic eruptions from regional fissure eruptions creating large amounts of material -basalts (milling) , hydroclastites and large pyroclastic debris flows in a subaqueous ( lake)setting- Rhyodacitic formations.( volcanic conglomerates).
My take is the same events are driving a large regional metasomatic system ie hydrothermal fluids ( probably sulphides)from deep down dissolving gold ( probably from the greenstones) and pushing it upwards towards surface under pressure and temperature.
Fluids using the vocanistic conglomerates due to high permeability and other pathways.
As hot fluids reach cooler zone further chemical changes take place, the fluid slows,condenses and releases the condensed gold out of solution . Higher less permeable conglomerate layers means less gold.(?)
Lava can typically reach over the melting point of gold so possibly the subsequent MRB flows results in baking the conglomerate and further concentration of some deposits into nuggets(?),then the capping and slowing of the erosional process.
Metasomatic systems in the Fortescue group have been studied and indicated regionally over a 450km x 200km area. Possibly more than twice.
I've relied on work done by Hickman, Blake , Thorne and Trendall, Huston, White, Van Kranendonk
and other teams who've studied the Pilbara over the decades. Plus a splash of tomato sauce.
Apologies for a few terms, just trying to be brief and concise. Good luck to all gold heads
Hundreds of cubic kilometres of rock sucked dry of gold and concentrated near surface sounds alright to me.

Expand

Thanks for this post Blue swims, the manner of emplacement or concentration appears complex and has been debated on these and other threads. Metasomatic activity certainly seems a valid option. I would like to follow up on some of your references if you could post more detail.

Cheers

BS

PIO Price at posting: 3.3¢ Sentiment: Buy Disclosure: Held
2 Upvote

0 Great analysis

Reply

Top Stories

KSN

Mineral Hill transition kicks off for Kingston, gold and silver ramp up to follow

NWH

NRW Holdings voted Wealth Within's hot stock tip

AIZ

Air New Zealand ditches 2030 emissions targets – right as ASIC's Scope 3 reporting changes kick in for FY25

Super PITch gold sponsor RSM Australia: Can Diggers & Dealers 2024 be key to reinvigorating IPO activity?

MTL

Mantle Minerals' Nick Poll talks to HotCopper on finding gold grades up to 3.57g/t at Mt Berghaus

There are more pages in this discussion • 65 more messages in this thread...

First 75 Last

Add ESS (ASX) to my watchlist

Ozwtisgold and PIO Reference, page-75

Top Stories

Mineral Hill transition kicks off for Kingston, gold and silver ramp up to follow

NRW Holdings voted Wealth Within's hot stock tip

Air New Zealand ditches 2030 emissions targets – right as ASIC's Scope 3 reporting changes kick in for FY25

Super PITch gold sponsor RSM Australia: Can Diggers & Dealers 2024 be key to reinvigorating IPO activity?

Mantle Minerals' Nick Poll talks to HotCopper on finding gold grades up to 3.57g/t at Mt Berghaus

Featured News