大洋铁锰矿床生长速率测定研究进展

大洋铁锰矿床的生长速率很慢，通常为数 mm/Ma，其壳层中记录了大洋海水与沉积环境的长期变化历史。常用的生长速率测定方法有：¹⁰Be和 U－Th系放射性同位素测年法、生物地层法、磁性地层法、稳定同位素法、基岩年龄推定法，以及经验公式计算法等。对大洋铁锰矿床生长速率的不同测定方法进行了全面回顾和总结，系统介绍了不同方法的原理、适用原则及优缺点，认为¹⁰ Be法是最为可靠的生长速率测定方法。在此基础上对大洋铁锰矿床生长速率测定的发展趋向作了预测，认为微区、微量高精度测试技术的运用，以及在深入研究元素与大洋铁锰矿床生长速率关系的基础上，建立合理有效的生长速率经验计算公式，可能是大洋铁锰矿床生长速率测定发展的基本趋势。

ADVANCES IN GROWTH RATE DETERMINATION OF OCEAN FERROMANGANESE DEPOSITS

Ocean ferromanganese deposits grow very slowly on sea floor at rates of several mm/Ma. These crust can therefore provide a long term history of the characteristics of sea water and sedimentary environment. Various dating methods have been proposed such as radiochemical dating by 10 Be and U Th series, biostratigraphy, magnetostratigraphy, Sr stable isotope method, estimates from the age of substrate, and determinates by regressive formulas. Different methods for growth rate determination of ocean ferromanganese deposits, their principle, apply fundamental and qualification have been summarized here, and the direction of growth rate determination have been prognosticated also. Proposing more available calculating formulas, based on detailed study between elements and growth rate of ocean ferromanganese crusts, and using of high precision determination methods on fine scale age dating, maybe the essential direction.