Pre-Meeting (May 14-17)
Introduction to Carlin Gold Deposits
(3 days – May 15-17, leave AM)
Twin Creeks, Turquoise Ridge
Overview Cortez Hills or Pediment
What are the classic features of this important class of gold deposits? Find out by visiting several major deposits along three major trends on this trip designed for geologists wanting an introduction to Carlin deposits or an update on the most current geologic thoughts about them.
Epithermal Deposits of the N. Nevada & SW Idaho
(4 days – May 14-17, leave AM)
Fire Creek, Mule Cnyn
This field trip will examine several epithermal precious metal deposits located along mid-Miocene rifts in northern Nevada and southwestern Idaho. The focus of the trip will be on deposit characteristics, host rocks, genesis, and exploration criteria, including the subtle expressions of the upper portions of bonanza ore shoots. This trip is designed for experienced geologists, mining engineers, and others seeking to learn about gold-silver deposits associated with Miocene-age volcanic rocks.
Seismic Hazards & Evolving Landscapes, Reno-Carson-Tahoe Area
(1 day – May 17, leave AM)
Petersen Mountain fault along Red Rock Road
Warm Springs Valley fault in the southern Honey Lake basin
This field trip will focus on research on the relative activity of earthquake faults in the northern Walker Lane, near Reno, Nevada. The northern Walker Lane accommodates ~7 mm/yr of right-lateral shear and contains numerous active faults capable of producing large earthquakes. Several recent paleoseimic studies have been completed in this area and have included mapping of Quaternary deposits and fault scarps, subsurface trenching, and geochronologic analyses on faulted deposits. We will visit several of the paleoseismic sites and discuss the geomorphic expression of active fault traces, the number and timing of paleo-earthquakes, and implications to seismic hazards assessment in the Reno area.
Structural Controls of Geothermal Systems
(2 days – May 16 & 17)
Hot Springs Mtns
Bradys Hot Springs, Desert Peak, San Emidio-Wind Mountain, Gerlach, Blue Mountain, Florida Canyon
Nevada has more geothermal resources than any other state, but most of these resources are hidden with no surface manifestations. This two day drip will examine the structural controls on currently active geothermal systems in western Nevada and the similarities between these present-day geothermal systems and late Miocene-Pliocene epithermal mineral deposits. In some areas, the current geothermal activity is collocated with the epithermal mineral deposits. We will focus on viewing several representative, favorable structural settings for hydrothermal systems and how we can apply this knowledge to both geothermal and mineral exploration.
The Famous Comstock Gold & Silver District
(1 day – Saturday May 16, leaving AM after ~1hr presentation)
Virginia City Epithermal district
This one day trip will explore the complex geologic setting of one of the richest epithermal districts in the U.S. The trip will consider the characteristics of several superimposed hydrothermal systems in the Virginia City area near Reno.
Post-Meeting (May 21-24)
Mesozoic Structures and Relationship to Carlin-style and Other Mineralization
(3.5 days – May 21-24, leave noon)
Nevada’s deep open pits are providing unprecedented opportunities to study ore-controlling structures, many of which have long and complex histories. Low-angle thrusts and other faults related to Mesozoic compression are now known to have been reactivated during important mineralizing events providing major channelways for Carlin-type gold fluids. This trip is designed for seasoned “Carlin” geologists and those interested in Mesozoic structures and their influence on important ore deposits.
Epithermal Deposits of the Walker Lane, Nevada
(3.5 days – May 21-24, leave noon)
Secret Cny & Daisy pits
Silicon, Sterling, N. Bullfrog
Exploration in the central portion of the Walker Lane has been hot in recent years. This field trip will examine the relationships between low-sulfidation, high-sulfidation, and sediment-hosted disseminated gold/silver deposits. Detachment tectonics will add some spice to this fascinating brew of deposits.