Heavy mineral compositions in the northeast sandy lands and the provenance analysis

To understand the role of play in the Asian aeolian dust system, the heavy mineral composition of the sandy land in Northeast China was analyzed. At present, in-depth study in this regard is lacking, which limited our understanding of the wind dust system in this area. Therefore, 34 samples of eolian and fluvial sand were collected from Onqin Daga sandy land (OD), Horqin sandy land (HQ), Hulun Buir sandy land (HL), and Songnen sandy land (SN), from which two particle-size fractions (＜63 μm, 63～125 μm) were processed and analyzed. In addition, four loess samples (＜63 μm) of the Last Glacial Period were collected from a loess profile in barren mountains near Harbin. The source areas of the Harbin loess were reconstructed quantitatively in the Frequentist model. After the range test, non-parametric Kruskal-Wallis H-test, and stepwise discriminant function analysis, seven heavy minerals (kyanite, anatase, garnet, pyroxene, ilmenite etc), and four characteristic indices indicating anti-erosion ability and mother-rock composition were selected for quantitative reconstruction. Results show that ilmenite (magnetic) is the characteristic mineral of OD, magnetite is that of HQ, iron oxide minerals (hematite, limonite) are those of HL, and iron oxide minerals (magnetic), epidote, amphibole and garnet are dominant minerals of SN. The contents of heavy minerals in various grain size fractions are different, and highly stable minerals are preferentially enriched in fine particles. The Harbin loess and SN and HL (＜63 μm component) have similar heavy mineral assemblages, but different from OD and HQ to some extents. The result of the Frequentist model shows that the contribution rate to the source of supply to the Harbin's loess is SN (44%～86%), HL (10%～39%), HQ (3%～16%), and OD (0～7%). This study highlights that the heavy mineral composition of fine sediment combined with the quantitative model has a good application prospect in the source tracing of wind dust.