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Gravity Data Highlights Structural Architecture of Irving Resources’ Omu Gold-Silver Project

Irving Resources Inc. is pleased to announce it has received a final report on gravity data collected at its 100%-controlled Omu high-grade gold-silver project, Hokkaido, Japan.

The recently completed 2017 exploration program at Omu was undertaken by Mitsui Mineral Development Engineering Co., Ltd. (MINDECO) under the supervision of Irving personnel. Data from the 2017 program including stream sediment analyses by bulk leach extractable gold (BLEG) method, detailed soil grid analyses and drone-based magnetics will be reported in a series of news releases over the next few weeks as it becomes available. Irving’s 2017 field program was geared toward target generation in preparation for more advanced work including trenching and drilling in 2018.

Gravity Data Reveals Structural Architecture of the Omu Project

Property-wide gravity data was collected at Omu over a two-month period earlier this year. Gravity data help discern changes in sub-surface rock density and are particularly helpful in highlighting the structural framework of the subsurface. The Bouger Anomaly Map (1st Vertical Derivative) presented in Figure 1 shows a north-northeast trending corridor of anomalously low density transecting the property. Irving interprets this to reflect a structural graben, or rift, likely related to tectonism that accompanied volcanism and mineralization in this area. Similar oriented structural features are associated with other Au-Ag vein systems in the region including Konomai mine, the largest historic producer on Hokkaido (Sumitomo Metal Mining Corp. Ltd., 1915-1973, 2.35 Moz Au, 38.6 Moz Ag). Also evident are discrete areas of higher density underlying each of the three main mineralized occurrences, Omui Mine, Hokuryu Mine and the recently discovered Omu Sinter.  In each case, these gravity highs may reflect areas where higher density basement sedimentary rocks are in closer proximity to surface. Identifying shallow basement highs was a critical component of exploration at the Hishikari Mine, Kyushu (Sumitomo Metal Mining Corp. Ltd., 1981-present, over 7 Moz Au), where veining focuses around basement domes.  Notwithstanding the production from other properties in the region, there can be no assurance that an economic deposit will be located on the properties in which the Company holds an interest.

A photo accompanying this announcement is available at

A plot of Horizontal Gradient presented in Figure 2 helps highlight structural zones including a pronounced feature extending from Omu Sinter in the north to Omui Mine in the south. This zone is interpreted to be the eastern margin of the rift system and may well be responsible for localizing the hydrothermal systems at both locations. Irving recently sampled epithermal vein mineralization grading 14.6 gpt Au and 50.8 gpt Ag along with strongly elevated arsenic (676 ppm), mercury (>100 ppm), antimony (1,675 ppm) and selenium (93 ppm), all elements indicative of hot spring mineralization, at the Omu Sinter (please refer to Irving’s news release dated September 21, 2017 for further detail). At Omui Mine, Irving has identified two areas of high-grade veining where recent vein samples have returned 186.5 gpt Au and 353 gpt Ag, 203 gpt Au and 5,310 gpt Ag, 11.75 gpt Au and 71.1 gpt Ag, 6.77 gpt Au and 33.3 gpt Ag, and 5.27 gpt Au and 177 gpt Ag at Honpi and 691 gpt Au and 515 gpt Ag, 42.5 gpt Au and 539 gpt Ag, 39.3 gpt Au and 20.2 gpt Ag, and 16.55 gpt Au and 40.9 gpt Ag at Nanko (please refer to Irving’s news release dated September 21, 2017 for further detail).  Interestingly, the historic Hokuryu Mine is situated along a northeast-trending structural corridor that appears to form the opposite side of the rift graben.

A photo accompanying this announcement is available at

“We are pleased with the results of our 2017 gravity survey,” commented Dr. Quinton Hennigh, Technical Advisor and a director of Irving. “We can now clearly see the structural control, effectively the plumbing system at Omu. The Omu Sinter seems to be along the same structure as Omui Mine, an important revelation. Hokuryu Mine sits astride the opposite structural zone on the other side of a distinct rift transecting the property. This data will prove very useful in targeting future exploration.”

Quinton Hennigh (Ph.D., P.Geo.) is the Qualified Person pursuant to National Instrument 43-101 responsible for, and having reviewed and approved, the technical information contained in this news release. Dr. Hennigh is a technical advisor and a director of Irving Resources Inc.


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