Study on ESR and TL dating for late Pleistocene rocks

(1)不适合热释光测年的非晶态石英可以用ESR法测年。石英样品的年龄范围为1000年至200万年。(2)在g=2.000~2.009的范围内有几个锆石的电子自旋共振信号，没有一个是由杂质离子引起的。信号g=2.008首先由掺钙锆石中的^&lt；4O&gt；Ca(n，α)^&lt；37&gt；Ar反应产生，表明它是由于天然锆石中放射性元素U和Th的α粒子解体所致。(3)锆石具有很强的热释光强度，是最适合测定年轻岩石年龄的矿物之一。(4)通过与锆英粉混合1个月或更长时间的剂量计热释光测量，可以很容易地估算出锆石的年剂量。(5)一种定量描述锆石晶体形态的新方法：它适用于地球科学的各个领域，包括基本锆石晶体与较老的偶然锆石晶体的区分。

(1) Ill-crystallized quartz, which is not suitable for TL dating can be dated by ESR method. The age range of quarts samples for ESR dating will be from 1000 years to 2 million years.(2) There are several ESR signals of zircon in a range from g=2.000 to 2.009, none of them being caused by impurity ions. The signal g=2.008 was first generated by ^<4O>Ca(n,alpha)^<37> Ar reaction in Ca-doped zircon, suggesting that it is due to the disintegration of alpha -particles from radioactive elements U and Th in natural zircon.(3) Zircon has very strong thermoluminescence intensities, and therefore is one of the most suitable mineral for dating young rocks. The intensity was confirmed to increase proportionally to the artificial gamma -rays irradiation doses.(4) The annual dose of zircon can be easily estimated from the TL measurement of dosimeters which are mixed with zircon powder for one month or longer.(5) A new method of describing zircon crystal morphology quantitatively: it is applicable to various fields of earth science, including the distinction of essential zircon crystals from older accidental ones.