Volcanic Eruptions and What Triggers Them

St. Helens erupted catastrophically at 8:32 a.m. on 18 May 1980 in southern Washington state, about 50 miles northeast of Portland (Oregon, USA). This eruption was preceded by a magnitude 5.1 earthquake and a subsequent landslide that are thought to have triggered the main eruption.

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Proficiency Testing: Knowing How Far You Can Trust Your Data

Proficiency testing (PT) is a cornerstone of good analytical practice, providing one of the few means of really testing the quality of a lab’s analytical output. Participation in a routine PT scheme can form part of lab accreditation, and for many industrial applications (e.g. ore grade determinations for the mining industry) it is often expected that mineral assay laboratories track their PT results. As an example, National Instrument 43-101, which is Canada’s “Standards of Disclosure for Mineral Projects”, requires the written disclosure of the methods used to verify quantitative data related to new mineral prospects seeking public funding. Hence, proficiency testing has become a de facto component of ore grade assessment whenever a mining company applies for listing on the Toronto stock exchange. Clearly, proficiency testing is not only of research importance but also plays a central role in the world’s mining industry.

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Carbonaceous Chondrite Impact Melts

Collisions between planetary bodies (such as asteroids colliding with one another or with planets) have played a role in the geologic evolution of our Solar System since the formation of planetesimals, the earliest kilometer-scale bodies. Shock damage from collisional impacts leaves evidence on surviving planetary materials that range in scale from kilometer-sized craters to nanometer-sized mineral structural defects.

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