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The Permian witnessed some of the most profound climatic, biotic, and tectonic events in Earth’s history. Global orogeny leading to the assembly of Pangea culminated by middle Permian time, and included multiple orogenic belts in the equatorial Central Pangean Mountains, from the Variscan-Hercynian system in the East to the Ancestral Rocky Mountains in the West. Earth’s penultimate global icehouse peaked in early Permian time, transitioning to full greenhouse conditions by late Permian time, constituting the only example of icehouse collapse on a fully vegetated Earth. The Late Paleozoic Ice Age was the longest and most intense glaciation of the Phanerozoic. Reconstructions of atmospheric composition in the Permian record the lowest CO2 and highest O2 levels of the Phanerozoic, with average CO2 levels comparable to the Quaternary, rapidly warming climate. Fundamental shifts occurred in atmospheric circulation: a global megamonsoon developed, and the tropics became anomalously arid with time. Extreme environments are well documented in the form of voluminous dust deposits, acid-saline lakes and groundwaters, extreme continental temperatures and aridity, and major shifts in biodiversity, ultimately culminating in the largest extinction of Earth history at the Permian-Triassic boundary.The Deep Dust project seeks to elucidate paleoclimatic conditions and forcings through the Permian at temporal scales ranging from millennia to Milankovitch cycles and beyond by acquiring continuous core in continental lowlands known to harbor stratigraphically complete records dominated by loess and lacustrine strata. Our initial site is in the midcontinental U.S.— the Anadarko Basin (Oklahoma), which harbors a complete continental Permian section from western equatorial Pangaea. We will also address the nature and character of the modern and fossil microbial biosphere, the chemistry of saline lake waters and groundwaters, Mars-analog conditions, and exhumation histories of source regions. Importantly, data from Deep Dust will be integrated with Earth-system modelling. This is crucial for putting the (necessarily local) drill core data into the broader global context and for understanding relevant mechanisms and feedbacks of the Permian Earth system. 

Abstract. The upper Paleozoic Cutler Group of southern Utah, USA, is a key sedimentary archive for understanding the Earth-life effects of the planet's last pre-Quaternary icehouse–hothouse state change: the Carboniferous–Permian (C–P) transition, between 304 and 290 million years ago. Within the near-paleoequatorial Cutler Group, this transition corresponds to a large-scale aridification trend, loss of aquatic habitats, and ecological shifts toward more terrestrial biota as recorded by its fossil assemblages. However, fundamental questions persist. (1) Did continental drift or shorter-term changes in glacio-eustasy, potentially driven by orbital (Milankovitch) cycles, influence environmental change at near-equatorial latitudes during the C–P climatic transition? (2) What influence did the C–P climatic transition have on the evolution of terrestrial ecosystems and on the diversity and trophic structures of terrestrial vertebrate communities? The Paleozoic Equatorial Records of Melting Ice Ages (PERMIA) project seeks to resolve these issues in part by studying the Elk Ridge no. 1 (ER-1) core, complemented by outcrop studies. This legacy core, collected in 1981 within what is now Bears Ears National Monument, recovered a significant portion of the Hermosa Group and the overlying lower Cutler Group, making it an ideal archive for studying paleoenvironmental change during the C–P transition. As part of this project, the uppermost ∼ 450 m of the core were temporarily transferred from the Austin Core Repository Center to the Continental Scientific Drilling Facility at the University of Minnesota for splitting, imaging, and scanning for geophysical properties and spectrophotometry. Here we (1) review the history of this legacy core, (2) introduce recently obtained geophysical and lithologic datasets based on newly split and imaged core segments to provide a sedimentological and stratigraphic overview of the Elk Ridge no. 1 core that aligns more accurately with the currently recognized regional lithostratigraphic framework, (3) establish the position of the boundary between the lower Cutler beds and the overlying Cedar Mesa Sandstone in the core, and (4) outline our ongoing research goals for the core. In-progress work on the core aims to refine biostratigraphic and chemostratigraphic age constraints, retrieve the polarity stratigraphy, interrogate preserved cyclostratigraphy, analyze sedimentary structures and paleosol facies, investigate stable isotope geochemistry, and evaluate elemental abundance data from X-ray fluorescence (XRF) scanning. Together with outcrop studies throughout Bears Ears National Monument and its vicinity, these cores will allow the rich paleontological and paleoenvironmental archives recorded in the continental Carboniferous–Permian transition of western North America to be confidently placed in a robust chronologic context that will help test hypotheses relating ecosystem evolution to the Carboniferous rainforest collapse, initial decline of the Late Paleozoic Ice Age, and long-wavelength astronomical cycles pacing global environmental change. 

Abstract Despite more than half a century of hominin fossil discoveries in eastern Africa, the regional environmental context of hominin evolution and dispersal is not well established due to the lack of continuous palaeoenvironmental records from one of the proven habitats of early human populations, particularly for the Pleistocene epoch. Here we present a 620,000-year environmental record from Chew Bahir, southern Ethiopia, which is proximal to key fossil sites. Our record documents the potential influence of different episodes of climatic variability on hominin biological and cultural transformation. The appearance of high anatomical diversity in hominin groups coincides with long-lasting and relatively stable humid conditions from ~620,000 to 275,000 yearsbp(episodes 1–6), interrupted by several abrupt and extreme hydroclimate perturbations. A pattern of pronounced climatic cyclicity transformed habitats during episodes 7–9 (~275,000–60,000 yearsbp), a crucial phase encompassing the gradual transition from Acheulean to Middle Stone Age technologies, the emergence ofHomo sapiensin eastern Africa and key human social and cultural innovations. Those accumulative innovations plus the alignment of humid pulses between northeastern Africa and the eastern Mediterranean during high-frequency climate oscillations of episodes 10–12 (~60,000–10,000 yearsbp) could have facilitated the global dispersal ofH. sapiens. 

Abstract. The Neogene and Quaternary are characterized by enormous changes in globalclimate and environments, including global cooling and the establishment ofnorthern high-latitude glaciers. These changes reshaped global ecosystems,including the emergence of tropical dry forests and savannahs that are foundin Africa today, which in turn may have influenced the evolution of humansand their ancestors. However, despite decades of research we lack long,continuous, well-resolved records of tropical climate, ecosystem changes,and surface processes necessary to understand their interactions andinfluences on evolutionary processes. Lake Tanganyika, Africa, contains themost continuous, long continental climate record from the mid-Miocene(∼10 Ma) to the present anywhere in the tropics and has longbeen recognized as a top-priority site for scientific drilling. The lake issurrounded by the Miombo woodlands, part of the largest dry tropical biomeon Earth. Lake Tanganyika also harbors incredibly diverse endemic biotaand an entirely unexplored deep microbial biosphere, and it provides textbookexamples of rift segmentation, fault behavior, and associated surfaceprocesses. To evaluate the interdisciplinary scientific opportunities thatan ICDP drilling program at Lake Tanganyika could offer, more than 70scientists representing 12 countries and a variety of scientificdisciplines met in Dar es Salaam, Tanzania, in June 2019. The teamdeveloped key research objectives in basin evolution, source-to-sinksedimentology, organismal evolution, geomicrobiology, paleoclimatology,paleolimnology, terrestrial paleoecology, paleoanthropology, andgeochronology to be addressed through scientific drilling on LakeTanganyika. They also identified drilling targets and strategies, logisticalchallenges, and education and capacity building programs to be carried outthrough the project. Participants concluded that a drilling program at LakeTanganyika would produce the first continuous Miocene–present record fromthe tropics, transforming our understanding of global environmental change,the environmental context of human origins in Africa, and providing adetailed window into the dynamics, tempo and mode of biologicaldiversification and adaptive radiations. 

Abstract. The primary scientific objective of MexiDrill, the Basin of MexicoDrilling Program, is development of a continuous, high-resolution∼400 kyr lacustrine record of tropical North Americanenvironmental change. The field location, in the densely populated,water-stressed Mexico City region gives this record particular societalrelevance. A detailed paleoclimate reconstruction from central Mexico willenhance our understanding of long-term natural climate variability in theNorth American tropics and its relationship with changes at higher latitudes.The site lies at the northern margin of the Intertropical Convergence Zone(ITCZ), where modern precipitation amounts are influenced by sea surfacetemperatures in the Pacific and Atlantic basins. During the Last GlacialMaximum (LGM), more winter precipitation at the site is hypothesized to have beena consequence of a southward displacement of the mid-latitude westerlies. Itthus represents a key spatial node for understanding large-scalehydrological variability of tropical and subtropical North America and isat an altitude (2240 m a.s.l.), typical of much of western North America. In addition, its sediments contain a rich record of pre-Holocene volcanichistory; knowledge of the magnitude and frequency relationships of thearea's explosive volcanic eruptions will improve capacity for riskassessment of future activity. Explosive eruption deposits will also be usedto provide the backbone of a robust chronology necessary for fullexploitation of the paleoclimate record. Here we report initial resultsfrom, and outreach activities of, the 2016 coring campaign.