SGER: Intensive Collection of Paleocene-Eocene Mammal Fossils and Development of a Stratigraphic Section in the Trans-Saharan Seaway (Mali)

SGER：古新世-始新世哺乳动物化石的密集采集和跨撒哈拉海道(马里)地层剖面的开发该项目由EAR(SGP)、环境生物学和国际科学与工程办公室共同资助。40-80英里的浅海淹没了现在被撒哈拉沙漠占领的地区，并支持了海洋和近岸物种的非凡多样性。这段时间间隔很重要，因为它还包括了地球历史上最后100 Ma有记录的一些最热的气候。然而，在这段时间里，已知的非洲热带地层剖面很少，也很少有发现大量脊椎动物化石的地层剖面。马里北部自那时以来拥有广泛的、相对未勘探的沉积矿床。我们在那里的初步工作(1999年、2003年)表明，利用脊椎动物、微型和大型无脊椎动物化石，开发跨越古新世-始新世(P/E)界线的陆地-近岸地层剖面具有很好的潜力。对该地区的地层学和系统古生物学的研究可以促进非洲热带地区P/E界线的区域性研究。在这里，我们提出了一个探索性研究的小赠款，在此期间，我们将对马里这些已知的化石岩石进行为期5周的探险(2009年1月)，主要目标有两个：(1)收集完整的和相关的哺乳动物和其他脊椎动物化石，(2)利用磁性地层学、化学地层学、层序地层学和生物地层学的组合，为这些脊椎动物的发现建立一个强大的地层框架。我们申请的紧迫性源于我们最近为实现这些目标授予了26,664美元的国家地理赠款。然而，这笔补助金的预算不包括与学生一起考察的费用，也不包括私人投资和合作投资的费用。然而，有了SGER的联合资金，我们将有能力发起一支完整规模的考察队，培训马里和美国的研究生，并将新的专业知识带到世界上一个可能产生发现的地区，这些发现可能会改变我们对非洲哺乳动物早期进化的知识。考察队将包括一个非马里团队：O‘Leary(哺乳动物系统学)、Roberts(层序地层学、沉积学)、Tapanila(生物地层学、遗迹学)、Goodwin(化学地层学)、Muttoni(磁性地层学)和McCartney(古生物学博士生)，以及一个马里团队Sissoko(哺乳动物进化)、Bouare(沉积学)、Cisse(博士生，沉积学)。我们已经证明了合作的能力，合作了两次探险，并发表了八篇联合论文。智力优点-我们的初步研究表明，横跨撒哈拉海道的马里沉积包含了热带非洲白垩纪-新近纪沉积最连续的记录。试点工作已经产生了几个明确的P/E段，其中包括P/E边界被限制在几米以内。这些区段的开发将为变革性研究奠定基础，为北美和亚洲研究充分的早第三纪盆地建立非洲比较。撒哈拉沙漠以南的P/E哺乳动物区段也非常罕见，但哺乳动物的分子系统发育研究预测，非洲此时拥有丰富的哺乳动物区系，有待发现。将在亚米级绘制和测量多个地层剖面，并进行详细的化石采样。识别相和关键表面将有助于在层序地层格架内对比剖面。物源、地球化学和化学地层学分析将有助于对比。磁极地层学的定向手样将在高分辨率(m尺度)下采集，并与测量的剖面捆绑在一起，重点放在显示恢复连续极性记录的潜力的剖面间隔上。两名学生-一名马里人和一名美国人将参加这次探险，并将发表有关发现的文章。

SGER: Intensive Collection of Paleocene-Eocene Mammal Fossils and Development of a Stratigraphic Section in the Trans-Saharan Seaway (Mali)Maureen O?LearyThis project is jointly funded by EAR (SGP), Environmental Biology, and the Office of International Science and Engineering. 40-80 mya shallow seas inundated the region now occupied by the Sahara Desert, and supported an extraordinary diversity of marine and nearshore species. This time interval is significant because it also included some of the hottest recorded climates of the last 100 Ma of Earth history. Few well-understood stratigraphic sections in this interval, however, are known from the African tropics, and even fewer that also yield extensive vertebrate fossils. Northern Mali has extensive, relatively unexplored sedimentary deposits from this time. Our preliminary work there (1999, 2003) indicates excellent potential for developing terrestrial-near shore stratigraphic sections spanning the Paleocene-Eocene (P/E) boundary, with vertebrate, micro-, and macroinvertebrate fossils. Study of the stratigraphy and systematic paleontology of this area could catalyze regional examination of the P/E boundary in the African tropics. Here we propose a Small Grant for Exploratory Research during which we would take a 5 week expedition (Jan. '09) to these known fossiliferous rocks of Mali with two major goals: (1) to target collection of complete and associated mammal and other vertebrate fossils, and (2) to establish a robust stratigraphic framework for these vertebrate discoveries using a combination of magnetostratigraphy, chemostratigraphy, sequence stratigraphy and biostratigraphy. The urgency of our application stems from our recent award of a National Geographic grant for $26,664 towards these goals. The budget of that grant does not, however, cover the cost of an expedition with students as well as the PI and co-PIs. With combined SGER funding, however, we would be capable of mounting a full-sized expedition that would train Malian and American graduate students, and bring new expertise to a region of the world that could yield discoveries transforming our knowledge of the early evolution of mammals in Africa. The expedition will include a non-Malian team: O'Leary (mammal systematics), Roberts (sequence stratigraphy, sedimentology), Tapanila (biostratigraphy, ichnology), Goodwin (chemostratigraphy), Muttoni (magnetostratigraphy), and McCartney (Ph.D. student, paleontology), and a Malian team Sissoko (mammal evolution), Bouare (sedimentology), Cisse (Ph.D. student, sedimentology). We have a proven ability to work together having collaborated on two expeditions and published eight joint papers.Intellectual Merit.- Our pilot research indicates that Malian deposits of the Trans-Saharan Seaway contain the most continuous record of Cretaceous-Neogene sedimentation in tropical Africa. Pilot work has resulted in several well-defined P/E sections that include the P/E boundary constrained to within several meters. Development of these sections would lay the groundwork for transformative research by establishing an African comparison for the well-studied Early Tertiary basins of North America and Asia. P/E mammal-bearing sections south of the Sahara Desert are also very rare, yet molecular phylogenetics research on mammals predicts that Africa had a rich mammal fauna at this time that remains to be discovered. Multiple stratigraphic sections will be mapped and measured at the sub-meter scale, and detailed fossil sampling undertaken. Identification of facies along with key surfaces will help correlate sections within a sequence stratigraphic framework. Provenance, geochemical, and chemostratigraphic analysis will aid in correlations. Oriented hand samples for magnetic polarity stratigraphy will be collected at high-resolution (m-scale) and tied to measured sections, with emphasis on intervals of section that display potential for recovery of a continuous polarity record.Broader Impacts - This project involves seven diverse scientists from American, European and African institutions. Two students - one Malian and one American will participate in the expedition and will publish on the discoveries.