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新近的大陆地壳化学组分模型建立在各种地球物理、地质和岩石学条件上,并显示较宽的组分变化范围。其中 SiO_2变化在(57～64)w_B%,K_2O 为(1.1～2.4)w_B%。大多数不相容元素有较高含量估值的模型暗示着这些元素在贫化地幔中极端亏损(>70%)。地壳热流制约着大陆地壳内产热元素(HPE:K,Th,U)的丰度,因而,为检验各种模型提供了一条明确而重要的途径。大陆热流中地壳放射性成因组分应在18～48mW/m~2范围内,并几乎肯定介于21～34 mW/m~2之间。后者限定了地壳中的 HPE 丰度(假设地壳厚度为41km,K/U=10000,Th/U=3.8),K_2O=0.96%～1.57%,Th=(3.0～4.94)×10~(-6),U=(0.80～1.30)×10~(-6)。主要根据地震或者地质填图资料建立的地壳区域模型以及那些认为大陆地壳较酸性且富集不相容元素的模型都超越了这些约束条件的上限。
The recent continental crust chemistry model is based on a variety of geophysical, geologic and petrological conditions and shows a wide range of compositional variability. Among them, the change of SiO 2 is (57-64) w_B%, K_2O is (1.1-2.4) w_B%. Models with higher content estimates for most of the incompatible elements imply extreme depletion (> 70%) of these elements in the depleted mantle. The crustal heat flow restricts the abundance of the heat-producing elements (HPE: K, Th, U) in the continental crust, thus providing a clear and important way to test various models. The radiogenic genetic component of the crust in the mainland heat flow should be in the range of 18-48 mW / m 2 and almost certainly be in the range of 21-34 mW / m 2. The latter limits the abundance of HPE in the crust (assuming a crust thickness of 41 km, K / U = 10000, Th / U = 3.8), K2O = 0.96% to 1.57%, Th = 3.0-4.94 × 10 ~ 6), U = (0.80 ~ 1.30) × 10 ~ (-6). The models of the crust region established mainly on the basis of seismic or geological mapping data, as well as those models that regard the continental crust as being more acidic and enriching incompatible elements, go beyond the upper limits of these constraints.