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采用Sm Nd同位素定年方法 ,测得江苏北部新沂地区踢球山三个榴辉岩岩体时代为 :2 2 1.6± 8.4Ma ,2 13.6± 9.2Ma和 2 16 .6± 8.1Ma;εNd(t)分别为 - 2 .9,- 2 .9和 - 3.0。采用Rb Sr定年方法得到其中一个榴辉岩的年龄为 2 0 1± 2 1Ma ;87Sr/ 86Sr =0 .70 5 35± 37。Sm Md年龄被看作为踢球山超高压变质之后板块折返过程中的高压榴辉岩相重结晶阶段年龄。Rb Sr年龄反映了踢球山榴辉岩体的板块折返过程中的角闪岩相退变质阶段开始年龄。为中朝板块与扬子板块碰撞时代主要发生在晚三叠世的观点提供了依据
Using Sm Nd isotope dating method, the age of three eclogite bodies of Kickball Mountain in Xinyi area of northern Jiangsu Province was measured: 2 2 1.6 ± 8.4Ma, 2 13.6 ± 9.2Ma and 2 16.6 ± 8.1Ma; εNd ( t) are -2.9, -2.9 and -3.0 respectively. The age of one of the eclogites obtained by the Rb Sr dating method is 2 0 1 ± 2 1Ma; 87Sr / 86Sr = 0 .70 5 35 ± 37. The Sm Md age is considered as the phase of recrystallization of high-pressure eclogites in the plate folding process after UHPM metamorphism. The age of Rb Sr reflects the age at which the amphibolite was experiencing metamorphism during the plate folding of the eclogites of the Kudushan eclogite. Provided the basis for the view that the collision between the North China Plate and the Yangtze Plate occurred mainly in the Late Triassic