Rock in Japan tells of Canada meteor impact 200 million years ago
Scientists working in Japan have discovered traces of a giant meteor impact that left a 100-kilometer crater in Canada more than 200 million years ago. A team of researchers led by Tetsuji Onoue, an assistant professor of geology at Kagoshima University, spotted fine spherical grains, apparent remnants of a meteor impact, in samples taken from a surface outcrop of deep-sea rock along the Kisogawa river in Sakahogi, Gifu Prefecture. Read more
Title: Shock veins in the central uplift of the Manicouagan impact structure: Context and genesis Authors: Marc B. Biren and John G. Spray
We describe the development of shock veins that penetrate the anorthositic central uplift of the Manicouagan impact structure. They occur as thin (< 2.5 mm wide), linear micro-fault systems that can be traced for several meters in length, and which predominantly trend radially from the point of impact. The shock veins are distinguished by the development of maskelynite along vein margins and stishovite in vein matrices, which are otherwise absent in non-veined regions.
Manicouagan Impact Research Program: MIRP (2007- )
This is a 10-year program involving studies of one of the best exposed of the larger terrestrial impact structures on Earth. MIRP is funded by NSERC, the Canada Research Chairs program, the Canadian Space Agency and industry. Approximately 10 km of Manicouagan drill core are housed off-campus, providing one of the most comprehensive impact crater repositories in the world. MIRP supports graduate students at the MSc and PhD levels, as well as Research Scientists, and welcomes international collaboration in areas of geochemistry, stable and radiogenic isotope studies, field mapping, mineralogy and petrology and shock processes. MIRP is managed by Research Scientist Dr Lucy Thompson. Read more
The Manicouagan impact structure is one of the largest impact craters still preserved on the surface of the Earth. The annular moat, prominent in space images, fills a ring where impact-brecciated rock was once eroded away by glaciation. The diameter of the original crater was approximately three times the size of this circular lake. Erosion has removed about a kilometre of rock from the region. The inner plateau remaining in the center of the annular moat is made up of metamorphic and igneous rock types along with melt sheet and is not as susceptible to glacial erosion.
Drilling update - Manicouagan meteorite impact site
- Five bore holes completed to date, further drilling on-going. - Disseminated sulphide mineralization (minor copper) was encountered in two holes, along with key Sudbury-type geological units in the additional holes, raising the level of prospectively within the crater itself. - Sudbury geology expert conducts detailed study of the Manicouagan impact site and drills cores, highlighting distinct similarities between the Sudbury and Manicouagan sites and further underscoring the discovery potential.
Manicouagan Minerals Inc. wishes to provide an update on the first part of its 10,400m drilling program on the 65km wide impact site at Manicouagan, Quebec. The results and studies obtained to date are indicative of the fact that the impact site's geological and dynamic parameters at the time of the massive meteorite impact, are amenable to the formation and accumulation of large ore bodies - similar to Sudbury.
Thus far a total of 3,460m of drilling in five bore holes have been completed within the 1,750 sq km property owned by Manicouagan, covering the 65 km diameter meteorite impact site. To date, the program has been equally divided between the inner crater areas where significant magnetotelluric (MT) anomalies are known to exist as well as the outer periphery of the island where at least twenty shallow MEGATEM anomalies are located.
The first hole (MAN-05-01) went to a depth of 1,607m to test an MT anomaly (No. 1). In this hole, minor copper (chalcopyrite) mineralization was noted in some restricted sections of the 650m thick impact related melt sheet. Two other shallower holes (MAN-05-02, MAN-05-03) were completed within the immediate camp area. The first hole (Man-05-03)located 400m north of the camp, cut a particularly thick section of the impact melt sheet throughout its entire 702m length, constituting the deepest section of the highly prospective melt sheet found to date. Sulphide mineralisation was also noted in this hole in the form of minute fracture fillings containing chalcopyrite, in addition to pyrite which is the dominant mineralization associated with the melt rock.
An additional drill hole (MAN-05-02) was drilled to a depth of 500 m to provide information on the area near the central meteorite uplift and related geophysical anomaly. Both holes encountered magnetite with only MAN-05-03 containing disseminated sulphides. Two further holes (MAN-05-04, MAN-05-05) were drilled as a partial cross-section to evaluate two MEGATEM EM anomalies on the west side of the island. These cut conductive shale units within remnants of Palaeozoic limestones near the edge of the reservoir. Dr. Walter Peredery, consulting geologist and expert on Sudbury geology, visited the project area in early September and concluded as follows in his September 20th, 2005 report:
"The Manicouagan Impact Melt Sheet (IMS) is surprisingly similar to the Sudbury Igneous-looking Complex noritic member. Both are coarse grained, and consist of the same mineralogy and contain high content of alkaline feldspars. Both contain relatively small amounts of sulphides. Manicouagan IMS (melt sheet) is a relatively thick sheet comparable to the norite in Sudbury. Fine-grained IMS phases exist at both Manicouagan and at Sudbury in the Onaping Formation. The presence of Basal Breccia unit both above and below the IMS at Manicouagan is similar to that found in the Sudbury structure. The presence of sulphides in the basement rocks is a feature of both the Manicouagan and the Sudbury structures. As such it is another positive element that must be a contributing factor in the formation of economic mineralization in the Impact structures."
Constantine Salamis, CEO, reports:
"The Manicouagan crater project has been fully initiated and has been a technical success with respect to the right mix of ingredients – in the form of Sudbury-style geology and minute sulphide mineralization - having been intercepted in the recent drilling. Disseminated sulphides occur as well in large fragments in melt rock and basalt immediately above the basement on the west side of the island. The large number of geophysical targets will extend the drill program at least until April, 2006. In addition, we are encouraged by the findings of our expert consultant in his comparison of Manicouagan to Sudbury."
Both Constantine Salamis and Dr. Walter Peredery qualify under the definition of "qualified person" set out in National Instrument 43-101 ("NI 43-101") and certify that by reason of education, affiliation with a professional association and past and relevant work experience, they both fulfil the requirements to be a "qualified person" for the purposes of NI 43-101.
The Company's management believes that the Manicouagan impact crater in Quebec may be an analogue to Sudbury, which at 360 million pounds of annual nickel production, is the second largest nickel camp in the world after Norilsk (in Russia). Statistically speaking, 36% of known impacts have significant mineralization in post-impact sediments, 25% of known impacts have associated mineral resources and 12% are currently being exploited or have been exploited in the past. The Manicouagan crater site is currently being tested for the first time using modern exploration techniques.