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研究的井冈山地区位于扬子地块与华夏地块之间,在早古生代寒武-奥陶纪时期沉积了巨厚的泥砂质韵律岩层夹碳酸盐岩和含炭岩层.它们具有低的εNd(t)值(–13.9～–7.9)和古老的Nd模式年龄(1842～2375Ma),数据点在tDM-tStr.图上远离一致线分布,在εNd(t)-tStr.图上都位于华南元古代地壳演化区域内.这些特征表明,本区寒武系和奥陶系主要是古元古代古老地壳组分再循环作用产物,物源以华夏地块区成熟度较高的陆源碎屑沉积岩为主.奥陶系爵山沟组和对耳石组的εNd(t)值(–10.5～–7.9)位于上述范围的高端,Nd模式年龄(1842～2059Ma)位于上述范围的低端,反映在它们沉积时期内,来自古元古代晚期-新元古代早期新生地壳物质的加入相对明显.鉴于在华夏地块和扬子地块东南缘范围内,早古生代地层的Nd模式年龄都大于1800Ma,没有发生明显的降低,反映在这些地区不存在早古生代亏损地幔来源岩浆活动.
The Jinggangshan area was located between the Yangtze block and the Cathaysia block and deposited in the Early Paleozoic Cambrian-Ordovician period with thick muddy rhythmic rock layers with carbonate and carboniferous strata with low εNd ( (-13.9 ~ -7.9) and ancient Nd model age (1842 ~ 2375Ma), the data points are far away from the consistent line distribution on tDM-tStr. These features indicate that the Cambrian and Ordovician in this area are mainly the products of the recycle of the ancient crustal components in the Paleoproterozoic. The provenance of the Cambrian and the Ordovician in this area is that the terrigenous clastic sedimentary rocks with high maturity in the Huaxia block are The εNd (t) values (-10.5 ~ -7.9) of the main Ordovician Jueshandang Formation and the otolith group are at the high end of the above range, and the Nd mode ages (1842 ~ 2059Ma) are located at the lower end of the above range, as reflected by their During the depositional period, the early Paleoproterozoic-Neoproterozoic crustal material addition was relatively obvious.During the southeastern margin of the Huaxia block and the Yangtze block, the Nd model ages of the Early Paleozoic strata were all greater than 1800 Ma, which did not appear obvious The decrease is reflected in the absence of pre-Paleozoic losses in these areas Mantle source of magma activities.