The Da Lat Zone in SE Vietnam consists of a Mesozoic orogenic belt that is characterised by abundant Cretaceous igneous rocks that were intruded into or deposited on Permo-Triassic rocks (represented by the Chau Thoi Formation) and Jurassic metasedimentary rocks. The three Cretaceous magmatic phases of the Dinh Quan, Deo Ca, and Ankroet suites of the Da Lat Zone were previously subdivided on the basis of geochemical and isotopic differences and related to within-plate and continental arc magmatism during Paleo-Pacific subduction. Limited dating gave varied estimates for crystallisation ages of the different suites. Here we present new whole-rock chemical data and LA-ICP-MS U-Pb zircon analyses for Cretaceous plutonic and volcanic rocks. The results indicate volcanic arc magmatism started in the Early Cretaceous, represented by the Dinh Quan suite at c. 113–135 Ma, and continued into the mid to Late Cretaceous (Deo Ca, Nha Trang, Dak Rium and Don Duong formations) with magmatism from c. 90 to 109 Ma. Granitoid basement rocks of the Cuu Long Basin yielded similar ages of c. 90 to 92 Ma, representing offshore equivalents. The Ankroet suite represents the youngest magmatic phase and is interpreted as within-plate magmatism from c. 75 to 87 Ma. The Cretaceous rocks generally have very few older zircons and their rarity is interpreted to indicate magmas were generated predominantly by melting of juvenile arc crust.

越南东南部的大叻地区由一个中生代造山带组成，其特征是丰富的白垩纪火成岩侵入或沉积在二叠纪-三叠纪岩石（以 Chau Thoi 组为代表）和侏罗纪变沉积岩上。大叻带的 Dinh Quan、Deo Ca 和 Ankroet 组的三个白垩纪岩浆相先前根据地球化学和同位素差异进行了细分，并与古太平洋俯冲期间的板内和大陆弧岩浆作用有关。有限的约会对不同套房的结晶年龄给出了不同的估计。在这里，我们展示了白垩纪深成岩和火山岩的新全岩化学数据和 LA-ICP-MS U-Pb 锆石分析。结果表明火山弧岩浆活动始于早白垩世，由 c. 的 Dinh Quan 套房代表。113-135 Ma，并持续到白垩纪中晚期（Deo Ca、Nha Trang、Dak Rium 和 Don Duong 地层），从 c. 90 到 109 毫安。Cuu Long 盆地的花岗岩类基底岩产生了相似的 c. 年龄。90 至 92 Ma，代表离岸等效值。Ankroet 组代表最年轻的岩浆相，被解释为来自 c. 的板内岩浆作用。75 至 87 毫安。白垩纪岩石通常很少有较老的锆石，它们的稀有性被解释为表明岩浆主要是由幼年弧形地壳熔化产生的。代表离岸等价物。Ankroet 组代表最年轻的岩浆相，被解释为来自 c. 的板内岩浆作用。75 至 87 毫安。白垩纪岩石通常很少有较老的锆石，它们的稀有性被解释为表明岩浆主要是由幼年弧形地壳熔化产生的。代表离岸等价物。Ankroet 组代表最年轻的岩浆相，被解释为来自 c. 的板内岩浆作用。75 至 87 毫安。白垩纪岩石通常很少有较老的锆石，它们的稀有性被解释为表明岩浆主要是由幼年弧形地壳熔化产生的。