All ICDP Publications with Abstracts
From parent-sysfolder "Publications" + 2 folder-levels deep
2944.
Foundational uncertainties in terminal Ediacaran chronostratigraphy revealed by high-precision zircon U-Pb geochronology of the Nama Group, Namibia
Earth-Science Reviews,
268
2025
2943.
Glass geochemistry and tephrostratigraphy of key tephra layers in and around Lake Van, Eastern Anatolian Volcanic Province (EAVP)
Quaternary Science Reviews,
352
2025
2942.
Hot-spring inputs and climate drive dynamic shifts in archaeal communities in Lake Magadi, Kenya Rift Valley
Biogeosciences,
22
(15)
3931 – 3948
2025
2941.
Identification of structures capable of hosting the ML 5.5 Orkney South Africa earthquake and factors controlling the physics and mechanics of dynamic rupture
Journal of the Southern African Institute of Mining and Metallurgy,
125
(1)
33 – 42
2025
2940.
Interlaboratory testing of thermal properties at ambient pressure on reference samples and core samples from the COSC-1 scientific drill hole, central Sweden
Geophysical Journal International,
241
(1)
405 – 436
2025
2939.
Legacy of mantle fabrics preserved within heavily serpentinized peridotites in Hole BA3A cores of the Oman Drilling Project
Lithos,
496-497
2025
2938.
Continuous Real-Time Detection of H2, He, and 222Rn While Drilling DIVE-1 Boreholes (ICDP) Indicates Deep Fracture Fluid Migration in Crystalline Rocks
Geochemistry, Geophysics, Geosystems,
26
(5)
2025
2937.
Metabolic features that select for Bathyarchaeia in modern ferruginous lacustrine subsurface sediments
ISME Communications
092024
ISSN: 2730-6151Abstract: ▾ Ferruginous conditions prevailed through Earth’s early oceans history, yet our understanding of biogeochemical cycles in anoxic iron-rich, sulfate-poor sediments remains elusive in terms of redox processes and organic matter remineralization. Using comprehensive geochemistry, cell counts and metagenomic data, we investigated the taxonomic and functional distribution of the microbial subsurface biosphere in Lake Towuti, a stratified ferruginous analogue. Below the zone in which pore water becomes depleted in electron acceptors, cell densities exponentially decreased while microbial assemblages shifted from iron- and sulfate-reducing bacterial populations to fermentative anaerobes and methanogens, mostly selecting Bathyarchaeia below the sulfate reduction zone. Bathyarchaeia encode metabolic machinery to cycle and assimilate polysulfides via sulfhydrogenase, sulfide dehydrogenase and heterodisulfide reductase, using dissimilatory sulfite reductase subunit E and rubredoxin as carriers. Their metagenome-assembled genomes showed that carbon fixation could proceed through the complete methyl-branch Wood-Ljungdahl pathway, conducting (homo)acetogenesis in the absence of methyl coenzyme M reductase. Further, their partial carbonyl-branch, assumed to act in tetrahydrofolate interconversions of C1 and C2 compounds, could support close interactions with methylotrophic methanogens in the fermentation zone. Thus, Bathyarchaeia appeared capable of coupling sulfur-redox reactions with fermentative processes, using electron bifurcation in a redox-conserving (homo)acetogenic Wood-Ljungdahl pathway, and revealing geochemical ferruginous conditions at the transition between the sulfate reduction and fermentation zone as their preferential niche.
2936.
Astronomical calibration of the Early Jurassic Sinemurian Stage based on cyclostratigraphic studies of downhole logging data in the Prees 2 borehole (Cheshire Basin, UK)
Newsletters on Stratigraphy,
57
(3)
257-282
072024
2935.
New constraints on the shear wave velocity structure of the Ivrea geophysical body from seismic ambient noise tomography (Ivrea-Verbano Zone, Alps)
Geophysical Journal International,
236
(2)
1089 – 1105
2024
2934.
Nanoscale Os isotopic quantification of Wadi Tayin dunite platinum group minerals by atom probe tomography
Lithos,
488-489
2024
2933.
Peak-ring magnetism: Rock and mineral magnetic properties of the
Chicxulub impact crater
GEOLOGICAL SOCIETY OF AMERICA BULLETIN,
136
(1-2)
307-328
2024
DOI:10.1130/B36547.1
2932.
Operational Dataset about drilling in the Moodies Group of the Barberton Greenstone Belt (BASE - Barberton Archean Surface Environments)
International Continental Scientific Drilling Program, GFZ German Research Centre for Geosciences
2024
Abstract: ▾ All datasets provided in the operational dataset (Heubeck et al., 2024) of the ICDP project BASE (ICDP 5069) consist of metadata, data and/or images. Here, a summary of explanations of the tables, data and images exported from the database of the project (mDIS BASE) are given and are complemented by additional information on data from measurements done in the laboratory prior to the sampling party. Finally, the sampling data from the first two sampling parties are added. Some basic definitions of identifiers used in ICDP, depths corrections and measurements are also introduced. The BASE (Barberton Archean Surface Environments) scientific drilling project focused on recovering unweathered continuous core through strata of the Paleoarchean Moodies Group (ca. 3.2 Ga), central Barberton Greenstone Belt (BGB), South Africa. They comprise some of the oldest well-preserved sedimentary strata on Earth, deposited within only a few million years in alluvial, fluvial, coastal-deltaic, tidal, and prodeltaic settings; they represent a very-high-resolution record of Paleoarchean surface conditions and processes. Moodies Group strata consist of polymict conglomerates, widespread quartzose, lithic and arkosic sandstones, siltstones, shales, and rare BIFs and jaspilites, interbedded with tuffs and several thin lavas. This report describes operations from preparations to the sampling workshop and complements the related scientific report. Eight inclined boreholes between 280 and 495 m length, drilled during November 2021 through July 2022, obtained a total of 2903 m of curated core of variable quality through steeply to subvertically dipping, in part overturned stratigraphic sections. All drilling objectives were reached. Boreholes encountered a variety of conglomerates, diverse and abundant, mostly tuffaceous sandstones, rhythmically laminated shale-siltstone and banded-iron formations, and several horizons of early-diagenetic sulfate concretions. Oxidative weathering reached far deeper than expected; fracturing was more intense, and BIFs and jaspilites were thicker than anticipated. Two km-long mine adits and a water tunnel, traversing four thick stratigraphic sections within the upper Moodies Group in the central BGB, were also sampled. All boreholes were logged by geophysical instruments. Core was processed (oriented, slabbed, photographed, described, and archived) in a large, publicly accessible hall in downtown Barberton. An exhibition provided background explanations for visitors and related the drilling objectives to the recently established Barberton-Makhonjwa Mountains World Heritage Site. A substantial education, outreach and publicity program addressed the information needs of the local population and of local and regional stakeholders.
2931.
Operational Report about drilling in the Moodies Group of the Barberton Greenstone Belt (BASE - Barberton Archean Surface Environments)
International Continental Scientific Drilling Program, GFZ German Research Centre for Geosciences
74
2024
Abstract: ▾ The BASE (Barberton Archean Surface Environments) scientific drilling project focused on recovering unweathered continuous core through strata of the Paleoarchean Moodies Group (ca. 3.2 Ga), central Barberton Greenstone Belt (BGB), South Africa. They comprise some of the oldest well-preserved sedimentary strata on Earth, deposited within only a few million years in alluvial, fluvial, coastal-deltaic, tidal, and prodeltaic settings and represent a very-high-resolution record of Paleoarchean surface conditions and processes. Moodies Group strata consist of polymict conglomerates, widespread quartzose, lithic and arkosic sand-stones, siltstones, shales, and rare BIFs and jaspilites, interbedded with tuffs and several thin lavas. This report describes operations from preparations to the sampling workshop and complements the related scientific report. Eight inclined boreholes between 280 and 495 m length, drilled during November 2021 through July 2022, obtained a total of 2903 m of curated core of variable quality through steeply to subvertically dipping, in part overturned stratigraphic sections. All drilling objec-tives were reached. Boreholes encountered a variety of conglomerates, diverse and abun-dant, mostly tuffaceous sandstones, rhythmically laminated shale-siltstone and banded-iron formations, and several horizons of early-diagenetic sulfate concretions. Oxidative weather-ing reached far deeper than expected; fracturing was more intense, and BIFs and jaspilites were thicker than anticipated. Two km-long mine adits and a water tunnel, traversing four thick stratigraphic sections within the upper Moodies Group in the central BGB, were also sampled. All boreholes were logged by geophysical instruments. Core was processed (ori-ented, slabbed, photographed, described, and archived) in a large, publicly accessible hall in downtown Barberton. An exhibition provided background explanations for visitors and relat-ed the drilling objectives to the recently established Barberton-Makhonjwa Mountains World Heritage Site. A substantial education, outreach and publicity program addressed the information needs of the local population and of local and regional stakeholders.
2930.
Origin of apatite-dominated rock penetrating the volcaniclastic fill of the Pleistocene Bažina maar (western Czech Republic)
Journal of Geosciences (Czech Republic),
69
(2)
113 – 127
2024
Keywords:▾
Czech Republic; apatite; enrichment; igneous geochemistry; maar; noble gas; penetration; Pleistocene; precipitation (chemistry); strontium isotope; volcaniclastic deposit
Abstract: ▾ The sequence of alkaline basaltic lavas and associated pyroclastic deposits that fill Bažina maar in western Bohemia is transected by a vein of apatite-dominated rock revealed in the S4 borehole. Aside from solid vein fill, apatite also impregnates a significant part of the drilled volcanic sequence. In the main body (depth 60.00–66.60 m), apatite occurs in two texturally distinct types: common cauliflower-type apatite (type 1) is transected by veinlets of coarser (0.2 mm long) apatite crystals (type 2). Both types have grown into open spaces suggesting precipitation from fluids rather than crystallization from melt, which is consistent with generally low trace element contents with slight enrichment in Cs, Sr, U and Pb. Relative to other local Plio-Pleistocene volcanic rocks, apatite vein-fill is shifted in87Sr/86Sr towards more radiogenic values (0.7053–0.7054). This suggests that fluids carrying mantle-derived ions mixed with groundwater interacting with granitic country-rock, as also evidenced by the purely crustal character of noble gases trapped in apatite. Unlike the mofettes occurring along the Mariánské Lázně Fault on the eastern margin of the Cheb Basin, the4He/3He ratios from Bažina apatite do not indicate mantle noble gas contribution. According to our model, the originally Sr–P-rich fluids with low87Sr/86Sr mixed with Cs–U-enriched groundwater circulating in country-rock granites with radiogenic 87 Sr/86Sr. Therefore, present-day CO2 outgassing through mofettes related mainly to the Mariánské Lázně Fault (eastern margin of the Cheb Basin) is likely independent of, and unrelated to, volcanism of the Cheb–Domažlice Graben. © 2024, Czech Geological Survey. All rights reserved.
2929.
Oxygen and silicon isotopic compositions of Archean silicified lava and cherts of the Onverwacht Group: Implication for seafloor hydrothermalism and the nature of recycled components in the source of granitoids
Chemical Geology,
670
2024
2928.
Paleogene Earth perturbations in the US Atlantic Coastal Plain (PEP-US): coring transects of hyperthermals to understand past carbon injections and ecosystem responses
Scientific Drilling,
33
(1)
47 – 65
2024
Keywords:▾
Carbon footprint; Coremaking; Earth system models; Infill drilling; Stratigraphy; Anthropogenics; Carbon injections; CO 2 emission; Coastal plain; Deep sea; Ecosystem response; Paleocene-Eocene boundaries; Paleocene-eocene thermal maximums; Paleogene; Short durations; Sea level
Abstract: ▾ The release of over 4500 Gt (gigatonnes) of carbon at the Paleocene–Eocene boundary provides the closest geological analog to modern anthropogenic CO2 emissions. The cause(s) of and responses to the resulting Paleocene–Eocene Thermal Maximum (PETM) and attendant carbon isotopic excursion (CIE) remain enigmatic and intriguing despite over 30 years of intense study. CIE records from the deep sea are generally thin due to its short duration and slow sedimentation rates, and they are truncated due to corrosive bottom waters dissolving carbonate sediments. In contrast, PETM coastal plain sections along the US mid-Atlantic margin are thick, generally having an expanded record of the CIE. Drilling here presents an opportunity to study the PETM onset to a level of detail that could transform our understanding of this important event. Previous drilling in this region provided important insights, but existing cores are either depleted or contain stratigraphic gaps. New core material is needed for well-resolved marine climate records. To plan new drilling, members of the international scientific community attended a multi-staged, hybrid scientific drilling workshop in 2022 designed to maximize not only scientifically and demographically diverse participation but also to protect participants’ health and safety during the global pandemic and to reduce our carbon footprint. The resulting plan identified 10 sites for drill holes that would penetrate the Cretaceous–Paleogene (K–Pg) boundary, targeting the pre-onset excursion (POE), the CIE onset, the rapidly deposited Marlboro Clay that records a very thick CIE body, and other Eocene hyperthermals. The workshop participants developed several primary scientific objectives related to investigating the nature and the cause(s) of the CIE onset as well as the biotic effects of the PETM on the paleoshelf. Additional objectives focus on the evidence for widespread wildfires and changes in the hydrological cycle, shelf morphology, and sea level during the PETM as well as the desire to study both underlying K–Pg sediments and overlying post-Eocene records of extreme hyperthermal climate events. All objectives address our overarching research question: what was the Earth system response to a rapid carbon cycle perturbation? © Author(s) 2024.
2927.
Plant cuticle as a possible palaeo-Hg proxy: Implications from Hg concentration data of extant Ginkgo L. and extinct ginkgoaleans
Palaeogeography, Palaeoclimatology, Palaeoecology,
647
2024
2926.
Nanoscale constraints on the nucleation and evolution of granular zircon from reidite in impactites at the Chicxulub impact structure
Earth and Planetary Science Letters,
626
2024
2925.
Leveraging Spatial Metadata in Machine Learning for Improved Objective Quantification of Geological Drill Core
Earth and Space Science,
11
(3)
2024
Keywords:▾
Oman; coordinate; data set; drilling; image analysis; machine learning; rock; satellite imagery; support vector machine
Abstract: ▾ Here we present a method for using the spatial x–y coordinate of an image cropped from the cylindrical surface of digital 3D drill core images and demonstrate how this spatial metadata can be used to improve unsupervised machine learning performance. This approach is applicable to any data set with known spatial context, however, here it is used to classify 400 m of drillcore imagery into 12 distinct classes reflecting the dominant rock types and alteration features in the core. We modified two unsupervised learning models to incorporate spatial metadata and an average improvement of 25% was achieved over equivalent models that did not utilize metadata. Our semi-supervised workflow involves unsupervised network training followed by semi-supervised clustering where a support vector machine uses a subset of M expert labeled images to assign a pseudolabel to the entire data set. Fine-tuning of the best performing model showed an f1 (macro average) of 90%, and its classifications were used to estimate bulk fresh and altered rock abundance downhole. Validation against the same information gathered manually by experts when the core was recovered during the Oman Drilling Project revealed that our automatically generated data sets have a significant positive correlation (Pearson's r of 0.65–0.72) to the expert generated equivalent, demonstrating that valuable geological information can be generated automatically for 400 m of core with only ∼24 hr of domain expert effort. © 2024 The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union.
2924.
Morphological variation in extinct Aulacoseira (Bacillariophyta) species from Lake Towuti, with a description of novel species
Journal of Great Lakes Research,
50
(3)
2024
2923.
Microbial diversity and biogeochemical interactions in the seismically active and CO2- rich Eger Rift ecosystem
Environmental Microbiome,
19
(1)
2024
2922.
Material and mechanical properties of young basalt in drill cores from the oceanic island of Surtsey, Iceland
Bulletin of the Geological Society of America,
136
(9-10)
3527 – 3552
2024
DOI:10.1130/B37037.1
Keywords:▾
Iceland; Surtsey; Basalt; Clay alteration; Drilling rigs; Pore size; Scale (deposits); Submarine geology; Underwater mineral resources; X ray diffraction analysis; Drill core; Fine ashes; Icelands; matrix; Mechanical; Oceanic islands; Property; Pyroclastic deposits; Sub-seafloor; Thermal; basalt; decadal variation; mechanical property; pyroclastic deposit; underwater environment; X-ray diffraction; Compressive strength
Abstract: ▾ Characterization of 2017 drill core samples from Surtsey, an oceanic island produced by 1963–1967 eruptions in the offshore extension of Iceland’s east rift zone, reveals highly heterogeneous microstructural, physical, and mechanical properties in subaerial, submarine, and subseafloor basaltic deposits. The connected porosity varies from 42% in weakly consolidated lapilli tuff in a submarine inflow zone to 21% in strongly lithified lapilli tuff in upper subseafloor deposits near the explosively excavated conduit. Permeability, however, varies over six orders of magnitude, from 10−18 m2 to 10−13 m2. Uniaxial compressive strength, P-wave velocity, and thermal conductivity are also highly variable: 10–70 MPa, 1.48–3.74 km·s−1, and 0.472–0.862 W·m−1·K−1, respectively. Synchrotron X-ray microdiffraction analyses integrated with major-element geochemistry and quantitative X-ray powder diffraction analyses describe the initial alteration of fresh glass, incipient consolidation of a fine-ash matrix, and partial closure of pores with mineral cements. Permeability, micromechanical, and thermal property modeling highlight how porosity and pore size in eruptive fabrics—modified through diverse cementing microstructures—influence the physical properties of the pyroclastic deposits. Borehole temperatures, 25–141 °C (measured from 1980 to 2018), do not directly correlate with rock strength properties; rather, the abundance and consolidation of a binding fine-ash matrix appears to be a primary factor. Analytical results integrated with archival data from 1979 drill core samples provide reference parameters for geophysical and heat transfer studies, the physical characteristics of pyroclastic deposits that lithify on a decadal scale, and the stability and survival of oceanic islands over time. For permission to copy, contact editing@geosociety.org © 2024 Geological Society of America
2921.
Living in the deep at the top of the world
Past Global Changes Magazine,
32
(2)
124-125
2024
2920.
Investigation of orbital and sub-orbital Milankovitch cycles from borehole logging data: Examples from Cretaceous and Quaternary lake sediments
Past Global Changes Magazine,
32
(2)
88-89
2024