| Aggraded red earth is the important carrier of the Quaternary environmental research, which is widely distributed in the Quaternary red earth in southern China. This article selected 45 samples of the aggraded red earth from Jiangxi province, Zhejiang province, Anhui province and Hunan province to explore the material source of the south subtropical aggraded red earth and environmental information in space. Meanwhile, it also chose several samples for comparison, for example,the eolian sand, Xiashu Loess and crusts of weathering. The heavy mineral clay samples were identified from aggraded red earth in the laboratory, and analyzed heavy mineral characteristics of each kind of aggraded red earth by the identification results of the heavy mineral. According to the appraisal result and the contrast of similarity analysis, and further discussed the physical contacts between them and aggradation type material sources of the clay. The preliminary conclusions are as follows:(1) Selected 45 aggraded red earth were identified in 10 heavy minerals, including pyrite (FeS2), hornblende, apatite, arsenopyrite (FeAsS), epidote, ilmenite (FeTiO3), limonite, sphene, zircon (ZrSiO4), pyroxene, white titanium ore (TiO2. NH2O), garnet, rutile (TiO2), tourmaline, and some quartzose detrital material. The identified the types of heavy mineral in add product type clay of aggraded red earth are similar, and most of these are stabilized and extremely stable and heavy mineral ilmenite, limonite and zircon. The second is anatase and white titanium ore,with unstable and relatively stable pyroxene, hornblende, galena, tremolite, garnet, epidote, heavy mineral be complementary. Heavy mineral combinations are similar on the whole,which are mainly stable, steady heavy mineral combinations, In a small number of samples contained in the heavy mineral combination is not stable or relatively stable minerals. Most of these heavy minerals in the aggraded red earth are angular, rounded shape, followed by angular, rounded shape seen in the least, and the particle size of focus is between 20 μm to 100 μm firstly, and 110 μm to 130 μm secondly.(2) Yellow brown soil of the communist party of China were identified of 18 kinds of heavy mineral,16 kinds of heavy mineral in Checker yellow brown soil, 18kinds of heavy minerals in the laterite,18 kinds of heavy mineral in Checker clay. In yellow brown soil, stability and extremely stable heavy mineral were averaged of 86.62%, heavy mineral of 3.976% on average, the more stable the unstable minerals were 3.088% on average, and Checker in yellow brown soil stability and extremely stable heavy mineral were averaged of 78.78%, heavy mineral of 2.946% on average, the more stable the unstable minerals was 6.75% on average,Stability in a homogeneous clay and extremely stable heavy mineral was of 89.07% on average. Only two homogeneous clay were detected in the relatively stable and heavy mineral, and stable and heavy minerals were not found in the homogeneous clay, and unstable minerals was 1.92% on average. In addition to some individual samples, stable and highly stable heavy minerals were averaged of 86.29%, heavy mineral of 1.044% on average, the more stable the unstable mineral had an average of 3.177%.Yellow brown soil of heavy mineral combination were mainly zircon ilmenite-red limonite and anatase, zircon and red limonite ilmenite-white titanium ore; Checker in yellow brown soil heavy mineral combination were mainly zircon-ilmenite-white titanium ore-sharp titanium, titanium iron ore-red limonite-zircon-anatase; Homogeneous clay in the heavy mineral combination and so on. There are mainly red-zircon-anatase titanium iron ore, ilmenite, zircon-anatase titanium ore-white. The heavy mineral combinations in reticulate red clay are mainly zircon ilmenite-white titanium ore-red limonite, titanium ore-red limonite-zircon-anatase, limonite-zircon-ilmenite-anatase.In addition, similarity degree of heavy mineral combination in yellow brown soil and checkered yellow brown soil is higher, Homogeneous clay and heavy mineral combination are closer to the reticulate red clay. The heavy mineral in four types of aggraded red earth is close, there is similar in content, composition, as well as some differences.(3)The heavy clay mineral characteristics index of aggraded red earth were analyzed as follows:Stability coefficient (W) of aggraded red earth is small, and is close to 0, which means that weathering of various aggraded red earth is stronger, and the weathering degree is similar; ATi index is 0, explains each kind of aggraded red earth excluding apatite; GZi index in Mao jiacun(MJC-03, MJC-01), Xinqiang (XQ-02) and Hehuaya(HH2-09) is larger, which are 23,25.55,25.21 and 25.55 respectively, followed by Xinqiang(XQ-04), Yue Mimigonglu (LMGL3-02, LMGL3-01),are 2.14,4.57,2.78 respectively. In addition, Fuluzhen(FLZ1-07) in the south of anhui, Pujiang (PJ-12) and Zhouhuacun(ZHC-01), Shengjilin(G-SJL-02), Xingzi county(XZX-01) in the surrounding areas of Poyang lake, GZi index is bigger than zero, but is in small amounts, which illustrates the aggraded red earth contains garnet; ZTR index of aggraded red earth is larger, lies between 12.13 to 42.56, shows that the heavy mineral accretion type clay is stable, and the heavier mineral characteristics index can be seen. All kinds of aggraded red earth are similar in the weathering degree, excluding apatite, heavy mineral are relatively stable, which explains aggraded red earth is consistent. The main source is similar,but some aggraded red earth contains garnet, this means some aggraded red earth are also affected by the local of weathering of rocks.(4)Contrast analysis from different parts of the source:Product type in the south of Anhui are similar with Xiashu Loess heavy mineral characteristics. With low similarity degree with local weathering crust, which illustrates the Xiashu Loess provides the main source for multiplicative clay-in the south of anhui and north of Zhejiang; Aggradation types of clay in Poyang lake region and Xiashu Loess are similar in heavy mineral characteristics, especially the further north shu loess parts are higher, which shows material relation between Poyang lake and Xiashu Loess. The change of contact material is latitude. In addition, the aggraded red earth in Poyang lake area is also influenced by surrounding dust sand, the Yangtze river sediments and local wind of weathering of rocks, the influence of sediment source is more complex. The aggraded red earth in Dongting lake surrounding area has a little contact with Xiashu Loess, more with Ruanjiang river sediments and rocks of weathering material. Overall, aggraded red earth and Xiashu Loess are close in physical contact, and have a certain latitude effect, red clay type in south latitude have less material contact than north latitude, which means a physical contact relationship between Xiashu Loess and aggraded red earth.To sum up, all kinds of aggraded red earth have greater consistency in the heavy mineral characteristics, which shows a common source. But the aggraded red earth in the south of Anhui and the north of Zhejiang are more close witn Xiashu Loess. Aggraded red earth in Poyang lake region has complex clay source, and the north part has closer relation with Ziashu Loess. The aggraded red earth in Dongting lake surrounding area has more than one source, and has little relation with Xiashu Loess, but closer to weathering of rocks and Ruanjiang river sediments. According to the size distribution of the heavy mineral and sand grinding roundness analysis of aggraded red earth, we know that aggraded red earth is mainly influenced by far source materials firstly, secondly affected by the proximal substances. Overall, aggraded red earth is a result of near source and distant source materials, the effect of source is complex. |
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