Geology & Mineralization
Regional Geologic Setting
The Mesquite district lies on the southwest flank of the Chocolate Mountains in the upper plate of a regional scale thrust fault. The host rocks represent a fragment of Precambrian and Mesozoic continental crust with an extremely complex metamorphic and structural history that largely pre-dates the Oligocene age gold mineralization being mined today.
The Mesquite Mine comprises a series of gold deposits localized along two sub-parallel zones of northwesterly trending faulting that overprints a sequence of gneissic host rocks and locally intruding granites. Much of the Mesquite district is covered by a veneer of unconsolidated post-mineral sand and gravel deposits that vary from a few to several tens of metres in thickness.
Deposit Geology – Plan View
Deposit Geology – Typical Cross Sections
Gold mineralization at Mesquite was deposited in an epithermal setting, within 150 to 300 metres of the paleo-surface subsequent to amphibolite grade metamorphism. The bulk of the gold mineralization occurs as disseminations and veins developed along a northwesterly trending system of moderately to steeply dipping faults and fractures. Gold primarily occurs as native gold, ranging in size from very coarse to submicron disseminations.
Since the commencement of commercial production in 1985, the Mesquite mine has produced more than 4 million ounces of gold.
The Mesquite Mine achieved commercial production in 2008 with most of the exploration work carried out by New Gold’s predecessors. Since acquiring the Mine in 2009, the company has conducted a series of drilling campaigns to explore potential extensions to the known ore bodies and to upgrade resource classification to support future mine planning. New Gold continues to conduct periodic exploration and delineation drilling campaigns to support ongoing reserves development and mine planning.