The ~790 ka Australasian (micro)tektite strewn field is one of the most recent and best-known examples of impact ejecta emplacement as the result of a large-scale cratering event across a considerable part of Earth's surface (>10% in area). The Australasian strewn field is characterized by a tri-lobe pattern consisting of a large central distribution lobe, and two smaller side lobes extending to the west and east. Here, we report on the discovery of microtektite-like particles in sedimentary traps, containing abundant micrometeorite material, in the Sør Rondane Mountain (SRM) range of East Antarctica. The thirty-three glassy particles display a characteristic pale yellow color and are predominantly spherical in shape, except for a single dumbbell-shaped particle. The vitreous spherules range in size from 220 to 570 μm, with an average diameter of ~370 μm. This compares relatively well with the size distribution (75–778 μm) of Australasian microtektites previously recovered from the Transantarctic Mountains (TAM) and located ca. 2500–3000 km from the SRM. In addition, the chemical composition of the SRM particles exhibits limited variation and is nearly identical to the ‘normal-type’ (i.e., <6% MgO) TAM microtektites. The Sr and Nd isotope systematics for a single batch of SRM particles (n = 26) strongly support their affiliation with TAM microtektites and the Australasian tektite strewn field in general. Furthermore, Sr isotope ratios and Nd model ages suggest that the target material of the SRM particles was composed of a plagioclase- or carbonate-rich lithology derived from a Paleo- or Mesoproterozoic crustal unit. The affiliation to the Australasian strewn field requires long-range transportation, with estimated great circle distances of ca. 11,600 km from the hypothetical source crater, provided transportation occurred along the central distribution lobe. This is in agreement with the observations made for the Australasian microtektites recovered from Victoria Land (ca. 11,000 km) and Larkman Nunatak (ca. 12,000 km), which, on average, decrease in size and alkali concentrations (e.g., Na and K) as their distance from the source crater increases. The values for the SRM particles are intermediate to those of the Victoria Land and Larkman Nunatak microtektites for both parameters, thus supporting this observation. We therefore interpret the SRM particles as ‘normal-type’ Australasian microtektites, which significantly extend the central distribution lobe of the Australasian strewn field westward. Australasian microtektite distribution thus occurred on a continent-wide scale across Antarctica and allows for the identification of new, potential recovery sites on the Antarctic continent as well as the southeastern part of the Indian Ocean. Similar to volcanic ash layers, the ~790 ka distal Australasian impact ejecta are thus a record of an instantaneous event that can be used for time-stratigraphic correlation across Antarctica.

约790 ka的澳大利亚（micro）陨石散布场是冲击射出定位的最新且最著名的例子之一，这是由于在地球相当大的一部分表面上发生了大规模的陨石坑事件（面积大于10％） 。澳洲散布场的特征是三叶形，由一个大的中央分布叶和两个向西和向东延伸的较小的侧叶组成。在这里，我们报道了在南极东部的SørRondane山（SRM）范围内的沉积陷阱中发现的微陨石样颗粒，其中含有丰富的微陨石材料。33个玻璃状颗粒显示出特征性的淡黄色，并且除了单个哑铃状颗粒外，其余均为球形。玻璃小球的大小范围为220至570μm，平均直径约为370μm。这与先前从跨南极山脉（TAM）中发现并位于加利福尼亚州南部的澳大利亚微晶石的尺寸分布（75–778μm）相比相对较好。距SRM 2500-3000公里。此外，SRM颗粒的化学成分表现出有限的变化，并且与“正常类型”（即<6％MgO）TAM微晶几乎相同。单批SRM颗粒的Sr和Nd同位素系统 6％MgO）TAM微晶。单批次SRM粒子的Sr和Nd同位素系统 6％MgO）TAM微晶。单批次SRM粒子的Sr和Nd同位素系统ñ = 26）强烈支持它们与TAM微晶石和澳大利亚的陨石散落场相关。此外，Sr同位素比率和Nd模型年龄表明SRM颗粒的目标材料由源自古生代或中生代地壳单元的富含斜长石或富含碳酸盐岩的岩性组成。与澳大利亚散落田地的隶属关系需要远距离运输，估计大圆距离约为。如果沿中央分布波瓣发生了运输，则距离假设的火山口11,600公里。这与从维多利亚州土地（约11,000公里）和拉克曼努纳塔克州（约12,000公里）回收的澳大利亚微晶岩的观察结果一致，平均而言，它们的大小和碱浓度会降低（例如，Na和K）随着距源坑的距离增加而增加。对于这两个参数，SRM粒子的值都在Victoria Land和Larkman Nunatak微晶岩的值中间，因此支持此观察。因此，我们将SRM颗粒解释为“正常类型”的澳大利亚微晶岩，它显着向西扩展了澳大利亚散布场的中央分布波瓣。因此，澳大利亚的微陨石分布发生在整个南极洲的整个大陆范围内，可以用来确定南极大陆以及印度洋东南部的新的，潜在的恢复地点。与火山灰层相似，约790 ka的澳大拉西亚远端撞击喷出物是瞬时事件的记录，可用于整个南极洲的时间地层相关性。