What is Sedex ore deposit?
Sedimentary exhalative deposits (SedEx or SEDEX deposits) are zinc-lead deposits originally interpreted to have been formed by discharge of metal-bearing basinal fluids onto the seafloor resulting in the precipitation of mainly stratiform ore, often with thin laminations of sulphide minerals.
What is sediment gold?
Sediment-hosted disseminated gold (SHDG) deposits comprise a major portion of the gold production and reserves in the US. Although presently known to be common only in western North America, SHDG deposits are a significant source of world gold production.
Is gold a sedimentary deposit?
All sediment-hosted gold deposits (as a single population) share one characteristic—they all have disseminated micron-sized invisible gold in sedimentary rocks.
What is Kuroko type deposits?
Synopsis. The Kuroko deposits of Japan are predominantly massive, stratiform sulphide ores with associated underlying stockwork ores of Miocene age in the Green Tuff volcanic sequences.
How are SedEx deposits formed?
SedEx, or sedimentary exhalative deposits, are ore deposits formed when hydrothermal fluids enter a water reservoir, such as an ocean, and precipitate minerals. SedEx deposits are a major source of minerals including copper, silver , gold and tungsten – and the single most important source of lead and zinc .
Where are gold deposits usually found?
About 244,000 metric tons of gold has been discovered to date (187,000 metric tons historically produced plus current underground reserves of 57,000 metric tons). Most of that gold has come from just three countries: China, Australia, and South Africa. The United States ranked fourth in gold production in 2016.
Where are gold deposits found?
Gold is usually found embedded in quartz veins, or placer stream gravel. It is mined in South Africa, the USA (Nevada, Alaska), Russia, Australia and Canada.
How many types of gold deposits are there?
orogenic gold deposits 2. Carlin-type gold deposits 3. epithermal deposits 4. porphyry copper-gold deposits 5.
How do SedEx deposits form?
What is Kuroko type of deposit How did this deposit form?
Kuroko deposits (Model 28a; Singer, 1986b) are typically developed in intermediate to felsic volcanic rock and are generally interpreted to have formed in extensional environments associated with arc volcanism. They are commonly high grade and can be very large.
Which ore minerals might be found in SedEx deposits?
How deep is gold usually found?
What is this? Orogon Gold Deposits – many of the larger gold deposits belong to this type and these deposits can be found at approximate depths of between 4000 feet and 15,000 feet. These deposits are typically caused by the formation of mountains and exist in marine deposits or in metamorphic rock.
What is the best gold placer deposit in Alabama?
The Arbacoochee Placer was the most extraordinary gold placer deposit in Alabama, covering 600 acres on top and sides of Gold Hill, once giving employment to 600 men. The Clear Creek placers were long famed for its rich production.
Where can I find placer gold in Georgia?
In the Verbena area all the streams and creeks surrounding the corners of Chilton, Coosa and Elmore Counties contain placer gold. On Blue Creek, the Rippatoe placers, discovered in 1835 to become a famous property with mining continuing vigorously until 1855.
What was the first paying copper mine in Alabama?
The Mossback Property and the Wood’s Hole Copper Mine were the first paying copper discoveries in Alabama, under an iron gossan with a by product of gold. The Pritchet Property had panning gold.