Come By Chance – Gold-Copper
Large Copper/Gold Porphyry Deposit Target
Belmont recently filed a 43-101 Technical Report on the Come By Chance Copper-Gold Project which further supports strong evidence of a copper gold porphyry systems. View video below. . .
Highlights of the Come By Chance 43-101 Technical Report
- At surface Crook Lake, appears as a hydrothermal or a collapsed breccia (caldera 1.) developed from an underlying intrusive. The evidence of a volcanic caldera is supported by a one kilometre diameter magnetic low within a sequence of Triassic Brooklyn Formation sedimentary and hornfelsed rocks which are bounded by the northwesterly trending Eagle Mountain Fault to the southwest and a sequence of greenstones, fragmentals, and microdiorite to the northeast.
- The highly anomalous arsenic content of Crook Lake may indicate the arsenic content from an alteration zone peripheral to an intrusive.
- The two surveys also revealed two significant cross-structural zones. The northern Crook Lake cross-structural location within the indicated caldera and the magnetic low, are of greater significance in that it may be the most obvious indication of a hydrothermal or collapsed breccia zone. In the south, one of the three structures formulating the cross-structure, is a southerly trending structure correlating with a magnetic low. This location would be also be highest priority exploration area.
- The significance of the cross-structures is primarily that these could be prime locations for hydrothermal breccia zones in revealing heterolithic fragments or indicator chemical elements transported to surface from a mineralized deep-seated intrusive porphyritic intrusive (as indicated by the mineralized copper-gold breccias at surface) responsible for the caldera, the skarns, and other types of mineral deposits.
- In addition to the potential of a mineral resource associated with a deep-seated mineral-bearing intrusive beneath the caldera there is the potential for an epithermal type deposit of a bonanza gold-bearing zone. This is indicated in the intersection of an epithermal vein by a drill-hole in the Betts area and also in the intersection of a “chute of massive sulphides in the 251 metre easterly driven lower Betts adit” (Minfile 082ESE261).
- The NI 43-101 Technical Report recommends an IP survey with an objective to map the resistivity and chargeability distribution which will assist in selecting specific diamond drill targets to test the copper-gold porphyry model.
The Importance of Hydrothermal Brecciation
Hydrothermal breccias usually form at shallow crustal levels (<1 km) between 150 and 350 °C, when seismic or volcanic activity causes a void to open along a fault deep underground. The void draws in hot water, and as pressure in the cavity drops, the water violently boils. In addition, the sudden opening of a cavity causes rock at the sides of the fault to destabilise and implode inwards, and the broken rock gets caught up in a churning mixture of rock, steam and boiling water. Rock fragments collide with each other and the sides of the void, and the angular fragments become more rounded. Volatile gases are lost to the steam phase as boiling continues, in particular carbon dioxide. As a result, the chemistry of the fluids changes and ore minerals rapidly precipitate. Breccia-hosted ore deposits are quite common.
The morphology of breccias associated with ore deposits varies from tabular sheeted veins and clastic dikes associated with overpressured sedimentary strata, to large-scale intrusive diatreme breccias (breccia pipes), or even some synsedimentary diatremes formed solely by the overpressure of pore fluid within sedimentary basins. Hydrothermal breccias are usually formed by hydrofracturing of rocks by highly pressured hydrothermal fluids. They are typical of the epithermal ore environment and are intimately associated with intrusive-related ore deposits such as skarns, greisens and porphyry-related mineralisation. Epithermal deposits are mined for copper, silver and gold.
Greenwood-Republic Mining Camp
Lidar Survey & Mineralized Showings
Magnetic Survey & Mineralized Showings
Conceptual Model for Styles of Epithermal Gold-Silver, Breccia and Porphyry Copper Mineralization
Come By Chance Brecciation
Explosive hydrothermal brecciation. The interesting feature is the light grey fragments which appear the color of arsenopyrite (FeAsS), a mineral that can also can be associated with significant amounts of gold
The brecciated quartz veins indicate the iron content was derived from metamorphism caused by the quartz intrusion; although the iron may have been emplaced at various stages.