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沉积物的地球化学和碎屑锆石特征在沉积岩物源分析及构造背景的研究中具有较为重要的作用.对克拉玛依后山地区早石炭世包古图组和太勒古拉组碎屑岩样品(共42个)进行了岩石学和地球化学研究,结果显示,这套碎屑岩的主量元素SiO2含量为54.64%~73.14%,Al2O3含量相对较高(11.89%~19.36%),(TFe2O3+MgO)含量比较高(3.97%~9.99%),反映岩石化学成熟度偏低.岩石稀土元素含量变化较大,在83×10-6~252×10-6之间变化,无Ce异常,Eu呈微弱负异常,具有低的∑REE等特征,与大洋岛弧型砂岩相似.采自这2个组的碎屑锆石U-Pb定年结果表明,包古图组有340Ma和440Ma两个主峰值,主要来源于石炭纪、志留纪的源岩;太勒古拉组碎屑锆石主峰值为325Ma,其年龄与地层年龄很接近,推测其主要来源于同沉积石炭纪岩石.根据主、微量及稀土元素等多个构造环境判别图解的综合分析,结果表明早石炭世包古图组和太勒古拉组沉积物的物源特征及沉积构造背景较为相似,主要为大洋岛弧-大陆岛弧环境下的中酸性火山岩,夹有少量基性火山岩.
The geochemistry and detrital zircon characteristics of sediments play an important role in the study of sedimentary provenance and tectonic setting.Based on the analysis of the Early Carboniferous Baogutu Formation and the Talagula detritus in the Karamay mountainous area (42 in total). The results show that the main elements of this set of clastic rocks are SiO2 (54.64% -73.14%), Al2O3 (11.89% -19.36%), (TFe2O3 + MgO) (3.97% ~ 9.99%), reflecting the low chemical maturity of rock.The content of rare earth elements in rock varies greatly from 83 × 10-6 to 252 × 10-6, without any abnormality of Ce, Eu is weakly negative anomaly and has a low ΣREE and other features similar to the Oceanic arc sandstone.The detrital zircon U-Pb dating from these two groups shows that there are two 340Ma and 440Ma The main peak value is mainly from the source rocks of Carboniferous and Silurian. The main peak value of detrital zircon in the Talauge Formation is 325Ma and its age is very close to the age of the strata, suggesting that it is mainly derived from the same sedimentary Carboniferous rocks. According to Main, trace and rare earth elements and other tectonic discrimination diagram of the comprehensive analysis of the results show that the early Carboniferous paleo-map group and Provenance and sedimentary deposits configured BACKGROUND Legu La group is similar, the main arc oceanic - acidic volcanic environment in the continental arc, a small amount of basic volcanic interposed.