Geochemical Characteristics Of Rare Earth Elements In Granitic Latosols In Hainan Island

In order to realize the geochemical characteristics of rare earth elements of granitic latosols in Hainan Island, REE contents of 80 samples and SREE contents of 10 samples were determined by using ICP-MS method. The results are described as follows:(1) In Hainan Island, the average gross of REE of granitic latosols is 426.96μg/g, while SREE is 199.06μg/g, all of these are higher than the mean value of earth crust and world soil. And the contents of SREE has positive correlation with REE. The mean value of∑Ce/∑Y is 4.48, which shows that latosol is rich in LREE and SLREE.(2) The mean values of REE gross were significantly different in three landforms of Hainan Island. The difference is in the order of middle mountain area(558.29μg/g)>low hill area(396.19μg/g)>table-coastal plain area area(313.11μg/g). LREE has the same distributing rules with the gross of REE in different landforms. The mean value of SREE is in the order of low hill area(287.92μg/g)>middle mountain area(167.69μg/g)>table-coastal plain area(141.58μg/g).(3) On vertical space, the mean value of REE of profile A in granitic latosols of Hainan Island is significantly dfrrerent from profile B and profile C, while it is not different between profile B and profile C. In different profiles , the mean value of REE contents reduce gradually from the bottom to the top, which is in the order of C(534.12μg/g)>B(512.39μg/g)>A(290.15μg/g). The mean value of SREE contents is in the order of B(281.07μg/g)> C(198.19μg/g)>A(117.92μg/g). The mean value of SREE contents of profile A is lower than B and C in different landforms except low hill area. LREE has the same rule with REE on vertical space. The mean value of HREE is in the order of B>C>A. In granite yellow-latosol and granite latosol, the mean values of REE and LREE have the same rules with table-coastal plain area and middle mountain area accordingly. The distributing patterns of SLREE and SHREE are the same to the mean values distributions of SREE in different landforms.(4) The mean value ofδEu is 0.46, which shows that the granitic latosol of Hainan Island belongs to the type of infirm-middle Eu depletion and negative Eu anomaly.δCe is in the range of 0.11 to 5.38, and the mean value is 1.02. In different profiles, the mean value ofδCe is in the order of A(1.34)>C(0.98)>B(0.86). Ce is positive anomaly and rich in the profile A of dffreren landforms and two kinds of granitic latosol and every profiles of table-coastal plain area, while in the depth of latosol, it is infirm negative anomaly and tends to be normal.