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Seabridge Gold Identifies a Large, Untested Target at Iskut Project

Wednesday, 26th October 2016

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Toronto, Canada...Seabridge Gold (TSX:SEA) (NYSE:SA) today reported that the 2016 multi-pronged exploration program on its 100%-owned Iskut Project in northwestern British Columbia has achieved its primary objective: to identify a prospective new porphyry copper-gold system with a potentially intact epithermal precious metals zone at its top, for drill testing in 2017.  

The untested target, known as Quartz Rise, has all the hallmarks of a porphyry lithocap, a geological feature found at the top of major porphyry systems throughout the world. A lithocap is a clay-silica-rich alteration feature which is a product of hydrothermal fluids escaping at the top of a porphyry mineralizing system. Typically, these features act as a cover obscuring structurally-controlled epithermal gold and silver systems that evolve from intrusive-related porphyry systems.

Commenting on the program, William Threlkeld, Seabridge's Senior Vice-President of Exploration, noted that the Quartz Rise target "has the right high temperature crystalline clay-silica alteration and a coincident magnetotelluric anomaly with the appropriate signature. Historical data from magnetic surveys support the lithocap hypothesis and iron mineral ratio analysis used successfully in the industry to identify productive lithocaps is also positive. Finally, and perhaps most importantly, we have taken samples of this lithocap that contain visible gold," Threlked said. "Collectively, these data point to a large and compelling target for the potential discovery of an intermediate-sulfidation epithermal precious metals system overlying porphyry copper-gold mineralization."

Seabridge completed a limited amount of drilling this summer at the old high grade Johnny Mountain gold mine to test detailed ore control concepts on a known deposit while proceeding with the comprehensive program.

"Our drilling confirmed the key structures that control mineralization and the likely elevation where we should expect to find higher grades. The old mine is found at the bottom of the slope and the high grade gold mineralization does not continue to depth. In our assessment, the Johnny Mountain mine is on the edge of a larger system and lies near the bottom of the productive gold-bearing zone which was largely eroded away by glaciation. The nearby, higher elevation Quartz Rise resisted glaciation and remains largely intact in part due to its higher silica content. We think the upper parts of a porphyry system with higher grades of precious minerals may lie intact above the Johnny Mountain mine and under the lithocap on Quartz Rise," said Threlkeld. (See image)


New Geophysical Work
Detailed magnetotelluric and airborne hyperspectral surveys were completed over Jurassic Hazelton Group rocks, the rocks that host many of the deposits in NW BC, on the west slopes of Johnny Mountain.  The purpose of these surveys was to identify the alteration patterns in the underlying rock formations.  Magnetotelluric (MT) technology acquires data over a large frequency band providing information on rocks to a potential depth of 3.0 kilometers and was used successfully at KSM to define the transition between peripheral alteration and mineralized zones at depth.  In the Johnny Mountain area, there are well defined vertical transitions between resistive and conductive rocks. These transitions were shown at KSM to represent contacts between mineralized rocks with high sulfide concentrations and altered rocks marginal to the mineral system.

A hyperspectral survey was also flown with sensors collecting data in wave lengths between 390nm to 2450nm with a 2.0 meter spatial resolution.  Images collected from the survey were geo-referenced and results were then placed into the correct surface position.  This data was collected to distinguish the various clay and iron oxide minerals that are exposed at the surface.  Mineral ratios can be interpreted to represent higher and lower temperature alteration zones.  The west slope of Johnny Mountain, the area around the mine that was extensively glaciated, shows the mineralogical characteristics of a marginal lower temperature alteration zone. The southwest facing, unglaciated slope of Quartz Rise has the mineral assemblage typical of more favorable, higher temperature epithermal alteration.

Compilation of Historical Data
Historical airborne magnetic data was compiled from surveys completed by previous owners.  These surveys show smaller, discrete magnetic highs in the glaciated parts of Johnny Mountain; however, a broader magnetic high is present under the unglaciated southwest facing slope.  The initial interpretation of this magnetic pattern is that a substantial intrusive body underlies this southwest facing slope.

Historical drill hole and surface geochemistry have also been evaluated.  Within the Johnny Mountain glaciated basin, surface and drill hole geochemistry show that gold concentrations are associated with two structural orientations, east-northeast and northwest.  In and around the Johnny Mountain Mine, northeast-trending silicic structures were exploited below surface gold anomalies.  Up slope and to the east of the mine, most of the anomalies are associated with northwest-trending clay-silica structures.  No drilling and very limited surface sampling was conducted on the unglaciated southwest slope of Johnny Mountain.

Historical core from the Johnny Mountain Mine was salvaged from 21 diamond drill holes.  These holes were reassembled, logged and sampled through intervals that, for the most part, had never been split and sampled. All of these shallow holes were drilled perpendicular to the strike of the northeast-trending silicic structures, but there were no intervals remaining in the core boxes from the principal structures exploited in the mine; however, assay reports were available that showed high grade gold over narrow intervals.  Several sub-parallel structures were identified from the logging and sampling of these holes. (See Appendix for details)

Drill Testing
Seabridge completed 3,368 meters of drilling on the Iskut project this year to obtain data on the structures that control gold concentrations.  The Johnny Mountain Mine area was selected to test for these controls because it provided abundant historical drill holes and ample underground data to expand upon the control concepts. 

An extensive zone of adularia-clay alteration with disseminated pyrite is hosted in flat laying tuffaceous units and phreatic breccia bodies around the Johnny Mountain Mine. The phreatic breccia is best developed in the hanging wall of northwest-trending structures and believed to be associated with fluid boiling along these structures.  Diorite intrusions were encountered at depth, their emplacement controlled by the northwest-trending structures and contacts within the tuff units. Structures crossed in the drill holes were principally semi-massive pyrite or intense silica replacement.  The pyrite-rich structures were best preserved near the margins of and within the diorite intrusion.

The drill program targeted a range of locations and elevations in the mine area, including:

  • Intersections in the west part of the Johnny Mountain Mine with holes JM-16-01, 02, 03, and 12.
  • Intersections in the central part of the Johnny Mountain Mine with holes JM-16-04, 05, 06 and 11.
  • Intersections in the south part of the Johnny Mountain Mine with holes JM-16-09, and 10.
  • An intersection in the east part of the Johnny Mountain Mine with holes JM-16-07, and 08.
  • A northwest trending structure identified in the MT survey, JM-16-13.

Several of the drill holes terminated in underground workings and did not test their intended targets.  Other holes did cross the intended structures and showed that multiple gold-bearing fluids with a diverse geochemical signature exploited the northwest-trending clay-silica structures.  The northeast-trending silicic structures seem to have focused the later gold-copper mineralizing fluids with the abundance and intensity of gold and hydrothermal alteration diminishing with depth. Observations from these drill holes support an interpretation that the Johnny Mountain Mine is on the margin of a larger mineral system, now believed to be southeast of the mine area (see image). For more detail see the Appendix.

Exploration activities by Seabridge at the Iskut Project are being conducted under the supervision of William E. Threlkeld, Registered Professional Geologist, Senior Vice President of the Company and a Qualified Person as defined by National Instrument 43-101. Mr. Threlkeld has reviewed and approved this news release. An ongoing and rigorous quality control/quality assurance protocol is employed in all Seabridge drilling campaigns. This program includes blank and reference standards. Cross-check analyses include metallic screen fire assay techniques and external laboratory analysis on at least 10% of the drill samples.

Seabridge holds a 100% interest in several North American gold projects. The Company's principal assets are the KSM Project located near Stewart, British Columbia, Canada and the Courageous Lake gold project located in Canada's Northwest Territories. For a full breakdown of Seabridge's mineral reserves and mineral resources by category please visit the Company's website at

Neither the Toronto Stock Exchange, New York Stock Exchange, or their Regulation Services Providers accept responsibility for the adequacy or accuracy of this release.

This document contains "forward-looking information" within the meaning of Canadian securities legislation and "forward-looking statements" within the meaning of the United States Private Securities Litigation Reform Act of 1995. This information and these statements, referred to herein as "forward-looking statements" are made as of the date of this document. Forward-looking statements relate to future events or future performance and reflect current estimates, predictions, interpretations, expectations or beliefs regarding future events and include, but are not limited to, statements with respect to: (i) the identification of a prospective new porphyry copper-gold system with a potential epithermal precious metals zone at its top that may be intact; (ii) the potential for discovery at the Iskut Project of an intermediate-sulfidation epithermal precious metals system overlying porphyry copper-gold mineralization; (iii) this year's drilling confirming the likely elevation where to find higher grades; (iv) the assessment that the Johnny Mountain mine is on the edge of a larger system and lies near the bottom of the productive gold-bearing zone which was largely eroded away by glaciation; (v) Seabridge thinking that the upper parts of a porphyry system with higher grades of precious minerals may lie intact above the Johnny Mountain mine and under the lithocap on Quartz Rise; (vi) the initial interpretation of the magnetic pattern found in the surveys of previous owners is that a substantial intrusive body underlies the southwest facing slope at Johnny Mountain; (vii) the northeast-trending silicic structures at Johnny Mountain seeming to have focused the later gold-copper mineralizing fluids with the abundance and intensity of gold and hydrothermal alteration diminishing with depth; and (viii) an interpretation from the drill hole results that the Johnny Mountain Mine is on the margin of a larger mineral system, now believed to be southeast of the mine area.

All forward-looking statements are based on Seabridge's or its consultants' current beliefs as well as various assumptions made by them and information currently available to them. Although management considers these assumptions to be reasonable based on information currently available to it, they may prove to be incorrect. Many forward-looking statements are made assuming the correctness of other forward looking statements.

Forward-looking statements involve various risks and uncertainties. There can be no assurance that such statements will prove to be accurate and actual results and future events could differ materially from those anticipated in such statements. Important factors that could cause actual results to differ materially from the Company's plans or expectations include the risk that the interpretations of the geologic formations at the Johnny Mountain mine do not conform to the geologic models that are the foundations for such hypotheses and other risks outlined in statements made by the Company from time to time in the filings made by the Company with securities regulators. A detailed cautionary statement outlining the forward looking statements in the mineral reserves and mineral resources reported by the Company, as well as assumptions and risks relating to them appears on its website. The Company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise, except as otherwise required by applicable securities legislation.

We caution readers not to place undue reliance on these forward-looking statements as a number of important factors could cause the actual outcomes to differ materially from the beliefs, plans, objectives, expectations, anticipations, estimates assumptions and intentions expressed in such forward-looking statements.


"Rudi Fronk"
Chairman and CEO

Rudi P. Fronk, Chairman and CEO
Tel: (416) 367-9292   ·  Fax: (416) 367-2711