Paleoclimate and paleoenvironment reconstruction of paleosols spanning the Lower to Upper Cretaceous from the Rukwa Rift Basin, Tanzania
Paleoclimate and paleoenvironment reconstruction of paleosols spanning the Lower to Upper Cretaceous from the Rukwa Rift Basin, Tanzania
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坦桑尼亚鲁夸裂谷盆地跨越下白垩统到上白垩统的古土壤的古气候和古环境重建
DOI：
10.1016/j.palaeo.2021.110539
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
O'Connor, Patrick M.
中科院分区：
文献类型：
--
作者：
Orr, Theresa J.;Roberts, Eric M.;Wurster, Christopher M.;Mtelela, Cassy;Stevens, Nancy J.;O'Connor, Patrick M.
白垩纪被认为是典型的温室间隔，但有越来越多的证据表明，在整个地质跨度间歇性较冷的气候阶段。在白垩纪，古赤道以南的大陆气候历史很少，而在这段时间里，非洲的大陆气候历史更少。白垩纪Galula组是现在亚赤道非洲的少数几个暴露的含盐大陆沉积序列之一，也包含古土壤，跨越早白垩世和晚白垩世系列。从Galula组层型剖面约500 m的古土壤中采集了大量沉积物和成土碳酸盐结核样品，其中4个来自Mtuka段（Aptian-Cenomanian）下部，4个来自Namba段（Cenomanian-Campanian）上部，以重建鲁夸河裂谷盆地的古气候和古环境。Mtuka古土壤是在半干旱气候条件下形成的沟道充填沉积物上发育的，在明确的干湿季节中主要产生垂直钙土。地球化学和形态气候函数确定，平均年降水量（MAP）增加了454至860毫米/年，而δ 18 O值的成壤碳酸盐和Bt层的主要元素古地温估计的年平均温度（MAT）保持相对稳定，在整个姆图卡成员之间的12.9和13.9 °C。上覆难波段的古土壤形成于靠近主河道的河道充填物和漫滩沉积物上，气候为半干旱至亚湿润，季节性很小，主要形成钙质粘质土。难波古土壤在稍微潮湿和凉爽的条件下形成，记录的MAP值在602至987毫米/年之间，MAT估计在10.3至12.5 °C之间。这些数据是一致的Mtuka古土壤对应的冷温室期间，跨越Aptian-Albian，与难波古土壤对应的晚白垩世冷却后的白垩纪热最大。这项工作表明，温带条件普遍存在于鲁夸河裂谷盆地在中晚白垩世。
The Cretaceous Period is considered the archetypical greenhouse interval, yet there is mounting evidence for intermittent cooler climatic phases throughout this geologic span. Few continental climate histories exist for the Cretaceous south of the paleoequator, and fewer still for Africa during this time. The Cretaceous Galula Formation is one of the few exposed fossiliferous continental sedimentary successions from what is now subequatorial Africa that also contains paleosols and spans both the Early and Late Cretaceous series. Bulk sediment and pedogenic carbonate nodules were sampled from paleosols located throughout ~500 m of the Galula Formation stratotype section, including four from the lower Mtuka Member (Aptian-Cenomanian) and four from the upper Namba Member (Cenomanian-Campanian), to reconstruct the paleoclimate and paleoenvironment of the Rukwa Rift Basin. The Mtuka paleosols developed on channel fill deposits in a semi-arid climate amidst well-defined wet and dry seasons that predominantly generated vertic Calcisols. Geochemical and morphological climofunctions determined that mean annual precipitation (MAP) increased up-section from 454 to 860 mm/yr, whereas theδ18O values of pedogenic carbonates and Bt horizon major-element paleothermometry estimated mean annual temperature (MAT) remained relatively steady, ranging between 12.9 and 13.9 °C throughout the Mtuka Member. The paleosols of the overlying Namba Member formed on channel fill and overbank deposits proximal to the main channels, in a semi-arid to sub-humid climate with little seasonality, forming mostly calcic Argillisols. The Namba paleosols formed under slightly wetter and cooler conditions, recording MAP values between 602 and 987 mm/yr, and MAT estimates between 10.3 and 12.5 °C. These data are consistent with the Mtuka paleosols corresponding to the cool greenhouse period that spanned the Aptian-Albian, with the Namba paleosols corresponding to Late Cretaceous cooling following the Cretaceous Thermal Maximum. This work demonstrates that temperate conditions prevailed in the Rukwa Rift Basin during the mid-Late Cretaceous.
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影响因子：
2.7
作者：
S. Marriott;V. Wright
通讯作者：
S. Marriott;V. Wright
影响因子：
5.8
作者：
L. Nordt;S. Driese
通讯作者：
L. Nordt;S. Driese
马斯特里赫特全球变暖期间阿拉斯加北极地区 Prince Creek 组的古气候重建
DOI：
10.1016/j.palaeo.2019.109265
发表时间：
2019
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
Susana Salazar;P. McCarthy;Andrés Ochoa;S. Fowell;F. Longstaffe
通讯作者：
F. Longstaffe
影响因子：
1.4
作者：
E. Gorscak;P. O’Connor;E. Roberts;N. Stevens
通讯作者：
E. Gorscak;P. O’Connor;E. Roberts;N. Stevens
通过地震反射数据分析比较坦噶尼喀、马拉维、鲁夸和图尔卡纳裂谷带
DOI：
--
发表时间：
1992
期刊：
影响因子：
--
作者：
B. Rosendahl;E. Kilembe;K. Kaczmarick
通讯作者：
K. Kaczmarick