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对川西盐边稗子田志留系剖面的野外调查和碳同位素样品采集,首次揭示了从兰多维列世晚期到罗德洛世早期地层中δ13 Ccarb连续变化曲线,并识别出两个碳同位素正漂移事件:温洛克世申伍德早期的艾尔韦克事件(Ireviken Event)(峰值位于下稗子田组中下部)和温洛克世侯默中期的墨尔德事件(Mulde Event)(峰值位于上稗子田组上部)。饶有兴趣的,一是其变化趋势与国际对比结果相符;二是在上覆地层中没有发现全球广布的罗德洛世晚期的劳事件(Lau Event),与王成源等(2009)在该地未找到与劳事件同期的牙形类化石不谋而合;三是从化学地层学角度证伪了该剖面志留系与泥盆系为连续沉积的观点。鉴于上述,认为运用δ13 Ccarb变化趋势进行志留系地层对比,不失为一种值得尝试且可付诸实践的新手段。对攀枝花—丽江地区志留系和华南板块、拉萨板块对比分析表明,当时该区既不属于华南板块,也不属于拉萨板块,而可能是位于两者附近的一个独立微块体。
Field surveys and carbon isotope sample acquisition of the Silurian section of the barnyard tidal fields in the western Sichuan Basin revealed for the first time the δ13 Ccarb continuous variation from the Late-Randian to the Late Rhodes stratigraphy and identified two carbon isotope positive Drift events: the Ireviken Event (peaked in the lower barren barley field) and the Mulde Event in the middle of Wylock-Houmer (the uppermost barnyardgrass Field group upper). Interestingly, the first is that the trend of change is consistent with that of international comparison. The second is that there is no widely recognized Lau Event in the overlying strata, which is similar to that of Wang Weiyuan et al. (2009) In the same time, the same type of fossils of dentoid fossils coincided with that of the workpieces. Thirdly, from the point of view of chemical stratigraphy, the viewpoints of the Silurian and Devonian series were deposited continuously. In view of the above, it is considered that using the δ13 Ccarb trend to compare the Silurian strata is a worthwhile attempt to put into practice. The comparative analysis of the Silurian-South China Plate and the Lhasa plate in the Panzhihua-Lijiang area shows that the area was neither a member of the South China nor the Lhasa plate but an independent micro-mass near the two.