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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Earth and Space Sciences · 术语表

什么是 Index mineral; isograd; metamorphic grade？

又称： metamorphic grade · index mineral · isograd

Definition 21.7 High School Earth and Space Sciences · 第 21 章 — Metamorphic Rocks

The metamorphic grade of a rock is the intensity of the metamorphism it went through, set by the temperature and pressure it reached. An index mineral is a mineral whose first appearance, in rocks of the same parent composition, marks a given grade. An isograd is the line on a map (a surface in the ground) joining the places where an index mineral first appears: along it, the rocks have reached the same grade.

A schematic map of metamorphic zones in rocks made from mud: each isograd (black line) marks the first appearance of an index mineral, and the grade rises towards the core of the belt, where the rocks were buried deepest and heated most. Real zones are bent and cut by folds and faults; their widths here are arbitrary.

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