Kent Dennis V, Olsen Paul E, Wang Huapei, Schaller Morgan F, Et-Touhami Mohammed
Biology & Paleoenvironment Division, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10968.
Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ 08854.
Proc Natl Acad Sci U S A. 2024 Nov 12;121(46):e2415486121. doi: 10.1073/pnas.2415486121. Epub 2024 Oct 28.
The end-Triassic extinction (ETE) on land was synchronous with the initial lavas of the Central Atlantic Magmatic Province (CAMP) and occurred just after the brief 26 thousand year (kyr) reverse geomagnetic polarity Chron E23r that can be used for global correlation. Lava-by-lava paleomagnetic secular variation data, previously reported from Morocco and northeastern United States combined with our data for the North Mountain Basalt from the Fundy Basin of Canada show that the initial phase of CAMP volcanism occurred in only five directional groups or pulses each occupying less than a century. The first four directional groups occur during a ~40 kyr period based on available astrochronology and U-Pb geochronology. The coincidence of the initial major pulse of CAMP volcanism with the ETE points to short-lived volcanic winters albedo-induced by sulfate aerosols as a plausible key agent of the extinctions in the tropical continental realm, whereas looser correlations allow prolonged CO emissions to contribute to more long-ranging effects in the marine realm via ocean acidification and longer-term warming.
陆地的三叠纪末大灭绝(ETE)与中大西洋岩浆省(CAMP)的初始熔岩活动同步,且发生在可用于全球对比的短暂的2.6万年(kyr)反向地磁极性时标E23r之后。先前从摩洛哥和美国东北部报道的逐熔岩古地磁长期变化数据,与我们对加拿大芬迪盆地北山玄武岩的数据相结合,表明CAMP火山活动的初始阶段仅出现在五个方向组或脉冲中,每个方向组或脉冲持续时间不到一个世纪。根据现有的天文年代学和铀铅年代学,前四个方向组出现在约4万年的时间段内。CAMP火山活动的初始主要脉冲与ETE的巧合表明,由硫酸盐气溶胶引起的短期火山冬季反照率是热带大陆地区灭绝事件的一个合理关键因素,而较松散的相关性则表明,长期的二氧化碳排放通过海洋酸化和长期变暖,对海洋领域产生更广泛的影响。