当前位置: X-MOL 学术Sediment. Geol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Recognition of Milankovitch cycles during the Oligocene–Early Miocene in the Zagros Basin, SW Iran: Implications for paleoclimate and sequence stratigraphy
Sedimentary Geology ( IF 2.8 ) Pub Date : 2021-06-16 , DOI: 10.1016/j.sedgeo.2021.105957
Omid Falahatkhah , Masoumeh Kordi , Vahid Fatemi , Hamed Hooshmand Koochi

Milankovitch cycles during the Phanerozoic affected paleoclimate, the onset/termination of glacial/interglacial periods, sea-level changes, and thus the distribution of different facies in sedimentary basins. The effects of astronomical forcing have been recorded as astronomical frequency signals in sedimentary sequences through geological history. In this research, for the first time, the signal of Milankovitch cycles and orbital obliquity modulation cycles from the Oligocene–Early Miocene Asmari Formation at one of the oil fields in the Dezful Embayment of the Zagros Basin, Iran, have been identified, through wireline logs. Based on that, ten ~1.2 orbital obliquity modulation cycles have been recognized and correlated with global third-order sequences and δ18O events. The number of cycles during the Oligocene–Early Miocene in the Asmari Formation is equivalent to obliquity of the La2004 orbital solution. Additionally, the optimal sediment accumulation rates, depositional duration of this formation, and foraminiferal biozone durations have been calculated. The result of this study shows that sediment accumulation rates varied in the range 2.9 to 3.2 cm/kyr. The foraminiferal biozones are diachronous in this area. Based on the identified 405 kyr long-eccentricity cycles in the three studied wells, three astronomical time spans of 11.5 Myr, 9.42 Myr, and 9.02 Myr were obtained for the Asmari Formation in Wells A, B, and C, respectively.



中文翻译:

伊朗西南扎格罗斯盆地渐新世-早中新世期间米兰科维奇旋回的识别:对古气候和层序地层的影响

显生宙米兰科维奇旋回影响古气候、冰期/间冰期的开始/结束、海平面变化,进而影响沉积盆地不同相的分布。通过地质历史,天文强迫的影响已被记录为沉积序列中的天文频率信号。在这项研究中,首次通过电缆识别了伊朗扎格罗斯盆地代兹富尔湾一个油田渐新世-早中新世阿斯马里组的米兰科维奇旋回和轨道倾角调制旋回信号。日志。在此基础上,已识别出 10 个 ~1.2 轨道倾角调制周期并与全球三阶序列和 δ 18 相关联哦事件。Asmari 组中渐新世-早中新世的循环次数相当于 La2004 轨道解的倾角。此外,还计算了最佳沉积物积累率、该地层的沉积持续时间和有孔虫生物区持续时间。这项研究的结果表明,沉积物堆积速率在 2.9 到 3.2 cm/kyr 的范围内变化。该地区的有孔虫生物区是历时的。根据在三个研究井中确定的 405 kyr 长偏心率循环,分别获得了 A、B 和 C 井 Asmari 组的三个天文时间跨度,分别为 11.5 Myr、9.42 Myr 和 9.02 Myr。

更新日期:2021-06-24
down
wechat
bug