All ICDP Publications with Abstracts
From parent-sysfolder "Publications" + 2 folder-levels deep
2828.
Reversed Holocene temperature–moisture relationship in the Horn of Africa
Nature,
620
(7973)
336 – 343
2023
2827.
Response of diatom assemblages to orbital- and millennial-scale climatic variability since the penultimate glacial maximum in the northern limit of the Neotropics
Journal of Quaternary Science
2023
ISSN: 02678179
Publisher: John Wiley and Sons Ltd
DOI:10.1002/jqs.3507
Abstract: ▾ Lake Chalco, in Central Mexico, has a long diatom record which provides an excellent opportunity to document the biotic and hydrological responses of this ecosystem to orbital- and millennial-scale climatic variability during the last 150 ka. Detrended correspondence analysis was used to evaluate the ecological turnover and to identify diatom species associations throughout the sequence. Millennial-scale climatic fluctuations were identified as peaks in freshwater (mostly small Fragilariaceae spp.) or as peaks in salt-tolerant species. At orbital scales, species turnover involved changes between freshwater assemblages dominated by Stephanodiscus spp. – small Fragilariaceae spp. – Cocconeis placentula, present during low-evaporation, cool intervals [late Marine Isotope Stage (MIS)6, MIS5d, MIS2] against salt-tolerant taxa, dominated by Stephanocyclus and Cyclotella spp., in higher evaporation, higher salinity conditions (MIS5e, MIS5c–a, MIS4, MIS3, early MIS1). Comparatively, MIS6 and MIS5d seem to have been cooler (~ −6 to −7 °C) and wetter than MIS2 (~ − 4 to −5 °C). In contrast, MIS5e and early MIS1 (11.5–6 ka) had similar warmer, low lake level, saline conditions. In addition, MIS5 was a period of intense climatic change associated with wide-amplitude orbital forcing that favored a Stephanocyclus–Cyclotella spp. ecological succession (S. meneghinianus, C. tlalocii, C. poyeka, S. quillensis). In contrast, smaller temperature changes were inferred during MIS4 and MIS3. © 2023 The Authors Journal of Quaternary Science Published by John Wiley & Sons Ltd.
2826.
Reconstruction of Dead Sea lake level and mass balance back to 237 ka BP using halite fluid inclusions
Quaternary Science Reviews,
303
2023
ISSN: 02773791
Publisher: Elsevier Ltd
Keywords:▾
Chloride minerals; Climate change; Evaporation; Fluid inclusion; Glacial geology; Lakes; Mineralogy; Sedimentology; Subsidence, Dead sea; Eastern Mediterranean; Fluid inclusion; Lake levels; Last glacial; Late quaternary; Mass balance; Southern levants; Water activity; Water evaporation, Sodium chloride, chronology; climate change; diapir; evaporation; freshwater; halite; Holocene; interglacial; lake level; lake water; Last Glacial; mass balance; sedimentation; solute; spectroscopy, Dead Sea; Israel; Levant; Mediterranean Region; Mount Sedom; Southern District
Abstract: ▾ The lake level of the Dead Sea, Southern Levant, has fluctuated with an amplitude of ∼250 m in response to the last glacial-interglacial cycle. This exceptional sensitivity to climate change, and the availability of long sedimentary archives, make the Dead Sea a benchmark for long quantitative paleohydrological reconstructions. However, discontinuities and chronological uncertainties in the marginal sedimentary record have hampered the reconstruction of Dead Sea lake levels beyond the Last Glacial (70–14 ka before present, BP). Here, we apply a two-pronged methodology. First, we measure the lake water density along ICDP deep core 5017-1-A using a new method, Brillouin spectroscopy on two-phase halite fluid inclusions; we combine it with the composition of pore water and the thickness of halite layers in the core to reconstruct lake level, volume, mass balance and subsidence rate. Second, we tune the chronology of lake levels from outcrops by matching it to the chronology of the deep core. The resulting lake level reconstruction, spanning 237–70 ka BP, is validated by the excellent agreement between outcrop- and mass balance-based methodologies. It shows a long-term recession of the lake, its level decreasing from one interglacial to the other, down to a Holocene record low. There are two reasons for this lake level fall. First, with an average rate of 2.65 ± 0.15 m/ka, subsidence has outpaced sedimentation at least over the last ∼130 ka. Second, by reducing the solute inventory of the lake, massive halite precipitation events such as that of 131–116 ka BP have durably increased surface water activity and evaporation, and thus lowered the lake level, up to today. Conversely, our analysis suggests that, during 191–11 ka BP, the dissolution of Mount Sedom salt diapir and freshwater inflows provided to the lake about three times the mass of solute NaCl contained in the modern Dead Sea (in 1985). This massive solute influx, occurring mainly during glacial highstands, strongly contributed to lowering surface water activity and evaporation and, therefore, to increasing the lake volume. Our results suggest that Dead Sea lake levels are more accurately interpreted in terms of climatic change if surface water activity is taken into account. © 2023 Elsevier Ltd
2825.
Re-investigations of the fossil fern Xiajiajienia mirabila (Dicksoniaceae) based on new material from the Lower Cretaceous of western Liaoning, China
Cretaceous Research,
149
2023
2824.
Radiolytically reworked Archean organic matter in a habitable deep ancient high-temperature brine
Nature communications,
14
(1)
6163
2023
ISSN: 20411723
Publisher: NLM (Medline)
Abstract: ▾ Investigations of abiotic and biotic contributions to dissolved organic carbon (DOC) are required to constrain microbial habitability in continental subsurface fluids. Here we investigate a large (101-283 mg C/L) DOC pool in an ancient (>1Ga), high temperature (45-55 °C), low biomass (102-104 cells/mL), and deep (3.2 km) brine from an uranium-enriched South African gold mine. Excitation-emission matrices (EEMs), negative electrospray ionization (-ESI) 21 tesla Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and amino acid analyses suggest the brine DOC is primarily radiolytically oxidized kerogen-rich shales or reefs, methane and ethane, with trace amounts of C3-C6 hydrocarbons and organic sulfides. δ2H and δ13C of C1-C3 hydrocarbons are consistent with abiotic origins. These findings suggest water-rock processes control redox and C cycling, helping support a meagre, slow biosphere over geologic time. A radiolytic-driven, habitable brine may signal similar settings are good targets in the search for life beyond Earth. © 2023. Springer Nature Limited.
2823.
Paleolimnological responses of Ecuadorian páramo lakes to local and regional stressors over the last two millennia
Journal of Paleolimnology
2023
Abstract: ▾ Increasing surface air temperatures and human influences (e.g., agriculture, livestock grazing, tourism) are altering lacustrine ecosystems in the South American Andean páramo, and these influences are evident in changes in the diatom-species composition in sediment cores from the region that span the last ~ 150 years. Existing studies are limited by their short temporal scales and limited spatial extent. We analyzed two sediment cores spanning the last two millennia from the northern (Laguna Piñan) and southern (Laguna Fondococha) Andean páramo of Ecuador to provide a longer-term perspective on lake dynamics. Both lakes show shifts in the dominant diatoms through time. Fondococha diatoms shifted in dominance between two Aulacoseira species and in the planktic to benthic ratio, and these shifts are interpreted as evidence of changing lake level. The inferred shifts are corroborated by changes in sediment geochemistry. Piñan shows a directional shift in the diatom assemblage over the period of the record, from benthic diatoms tolerant of high dissolved organic carbon (DOC), low pH, and low nutrients, to an assemblage characteristic of lower DOC, Melina use only one higher for pH, nutrients and lake levels. Shifts in Piñan’s diatoms are correlated with tephra layers in the sediment, suggesting that local volcanic deposition may have been responsible for altering the catchment and lake geochemistry. This is supported by relatively high δ13C values in organic matter associated with tephra layers, which become more negative up-section. Our study suggests that remote lakes in spatially heterogenous montane regions act as sentinels of different facets of environmental change and provide insights into Andean ecosystem responses to environmental perturbations. © 2023, The Author(s), under exclusive licence to Springer Nature B.V.
2822.
Pore Connectivity of Deep Lacustrine Shale and its Effect on Gas-bearing Characteristics in the Songliao Basin: Implications from Continental Scientific Drilling
Acta Geologica Sinica (English Edition),
97
(5)
1503 – 1522
2023
2821.
Planning for the Lake Izabal Basin Research Endeavor (LIBRE) continental scientific drilling project in eastern Guatemala
Scientific Drilling,
3285-100
2023
2820.
Pervasive carbonation of peridotite to listvenite (Semail Ophiolite, Sultanate of Oman): clues from iron partitioning and chemical zoning
European Journal of Mineralogy,
35
(2)
171 – 187
2023
Keywords:▾
Oman; Semail Ophiolite; Iron oxides; Magnesite; Quartz; Serpentine; Textures; Zoning; Chemical zoning; Convergent plate boundaries; Last stage; Mantle rocks; matrix; Mid-ocean-ridge; Quartz rocks; Reaction zones; Serpentinized peridotites; Sultanate of Oman; carbonate; iron; manganese; metasomatism; mid-ocean ridge; peridotite; quartz vein; ultramafic rock; Carbonation
Abstract: ▾ Earth's long-term cycling of carbon is regulated from mid-ocean ridges to convergent plate boundaries by mass transfers involving mantle rocks. Here we examine the conversion of peridotite to listvenite (magnesite + quartz rock) during CO2 metasomatism along the basal thrust of the Semail Ophiolite (Fanja, Sultanate of Oman). At the outcrop scale, this transformation defines reaction zones, from serpentinized peridotites to carbonated serpentinites and listvenites. Based on a detailed petrological and chemical study, we show that carbonation progressed through three main stages involving the development of replacive textures ascribed to early stages, whilst carbonate (± quartz) veining becomes predominant in the last stage. The pervasive replacement of serpentine by magnesite is characterized by the formation of spheroids, among which two types are identified based on the composition of their core regions: Fe-core and Mg-core spheroids. Fe zoning is a type feature of matrix and vein magnesite formed during the onset carbonation (Stage 1). While Fe-rich magnesite is predicted to form at low fluid XCO2 from a poorly to moderately oxidized protolith, our study evidences that the local non-redox destabilization of Fe oxides into Fe-rich magnesite is essential to the development of Fe-core spheroids. The formation of Fe-core spheroids is followed by the pervasive (over-)growth of Mg-rich spheroids and aggregates (Stage 2) at near-equilibrium conditions in response to increasing fluid XCO2. Furthermore, the compositions of carbonates indicate that most siderophile transition elements released by the dissolution of primary minerals are locally trapped in carbonate and oxides during matrix carbonation, while elements with a chalcophile affinity are the most likely to be leached out of reaction zones. © 2023 Thierry Decrausaz et al.
2819.
Parapatric speciation of <i>Meiothermus</i> in serpentinite-hosted
aquifers in Oman
FRONTIERS IN MICROBIOLOGY,
14
2023
Keywords:▾
subsurface; serpentinite; recombination; evolution; geographic
isolation; parapatric speciation; dispersal limitation; competitive
exclusion
2818.
Palynological characteristics of plant communities in the eastern Arctic during the Early to Middle Calabrian Age
Review of Palaeobotany and Palynology,
315
2023
Keywords:▾
Anadyr; Arctic; Chukchi; Elgygytgyn Lake; Russian Federation; Calabrian; paleoclimate; palynology; plant community; Pleistocene; pollen; shrub; vegetation history
Abstract: ▾ Palynological analysis of Early Pleistocene sediments from Lake El'gygytgyn indicate that climate was warmer than present between c. 1.2860 and 1.6975 Ma (late Gelisian–early Calabrian ages), although variations in the paleovegetation indicate fluctuations between relatively cool and warm conditions. During the coolest intervals, the vegetation on the Anadyr Plateau was a mix of Betula-Salix shrub tundra and Larix forest-tundra. Larix forests, which probably included trees species of Betula and Alnus, characterized the regional vegetation during the warmest times. Slightly cooler interglaciations are indicated by the presence of Larix-forest tundra. Pinus pumila pollen is not consistently present in all interglaciations, indicating that variations in the extent and/or duration of snow cover occurred during these warm intervals. The absence of pollen from this evergreen shrub contrasts with Holocene and Late Pleistocene assemblages, where the taxon is a hallmark of warm conditions. During the Early Pleistocene, Betula pollen indicates the plant's presence during warm and cool intervals, in contrast to Late and Middle Pleistocene spectra where shrub Betula is absent or rare. The pollen data from MIS 55 suggest that it was the coolest of the Pleistocene “super” interglaciations and that the MIS 43 climate was as warm as that of MIS 55. The El'gygytgyn palynological record is a powerful reminder that the distribution of arctic communities can be vastly reduced or eradicated during warm Earth scenarios. © 2023 Elsevier B.V.
2817.
Paleolakes of Eastern Africa: Zeolites, Clay Minerals, and Climate
Elements,
19
(2)
96 – 103
2023
Keywords:▾
East African Rift; Alkalinity; Climate change; Lakes; Zeolites; Alkalines; Changing climate; Climate; Climate condition; Condition; East African Rift; Eastern Africa; High pH; Paleolake; Rift systems; clay mineral; climate change; lake water; paleoclimate; paleoenvironment; water chemistry; zeolite; Clay minerals
Abstract: ▾ The eastern branch of the East African Rift System hosts many shallow modern lakes and paleolakes, which can be sensitive recorders of changing climate conditions (complicated by tectonics) during the past few million years. However, many of such lakes are saline–alkaline (salty and high pH), and these conditions do not easily preserve pollen and other biologically derived paleoclimate indicators. Fortunately, some preserved minerals that formed in these extreme environments reflect subtle shifts in lake water chemistry (controlled by changes in climate conditions) and therefore provide a continuous record of local and regional climate change. We present two different mineral proxies (zeolites and clays) from two different paleolake basins (Olduvai Gorge, Tanzania, and Chew Bahir, Ethiopia) as examples. © 2023 Mineralogical Society of America. All rights reserved.
2816.
Paleoenvironmental changes across the Mesozoic-Paleogene hyperthermal
events
GLOBAL AND PLANETARY CHANGE,
222
2023
Keywords:▾
Mesozoic -Paleogene; Hyperthermal events; Climate change;
Paleoenvironment
2815.
Special Issue on Ophiolites and Oceanic Lithosphere
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,
128
(4)
2023
2814.
Paleo-Permeability Structure of the Crustal Section of the Samail Ophiolite Based on Automated Detection of Veins in X-Ray CT Core Images From the Oman Drilling Project
Geochemistry, Geophysics, Geosystems,
24
(6)
2023
2813.
Significance of Secondary Fe-Oxide and Fe-Sulfide Minerals in Upper Peak Ring Suevite from the Chicxulub Impact Structure
Minerals,
13
(3)
2023
2812.
Two Small Volcanoes, One Inside the Other: Geophysical and Drilling
Investigation of Bazina Maar in Western Eger Rift
EARTH AND SPACE SCIENCE,
10
(8)
2023
Keywords:▾
maar-diatreme volcano; magnetometry; electrical resistivity tomography;
drilling; gravity survey; Eger Rift
2811.
Study of Depression and Layer Controlled Geothermal System in Songliao Basin (in Chinese with English abstract);[松辽盆地坳陷层控地热系统研究]
Acta Geoscientica Sinica,
44
(01)
21-32
2023
2810.
Timing and recurrence intervals for voluminous silicic eruptions from
Amatitlan caldera (Guatemala)
QUATERNARY SCIENCE REVIEWS,
301
2023
Keywords:▾
Quaternary geochronology; Zircon; (UeTh)/He; SIMS; Central America;
40Ar/39Ar
2809.
Olivine—The Alteration Rock Star
Elements,
19
(3)
165 – 172
2023
Keywords:▾
Carbon dioxide; Earth (planet); Olivine; Stars; Alteration; Aqueous fluids; Exposed to; Physical and chemical properties; Star-like; Tectonic plates; Upper mantle; carbon dioxide; chemical alteration; olivine; serpentine; upper mantle; Serpentine
Abstract: ▾ Olivine is the main component of the Earth’s upper mantle, on which our tectonic plates rest. As such, olivine has been studied since the dawn of geology and is regarded as the storyteller of the Earth’s interior. Its physical and chemical properties provide insight into its creation in magmas and its voyage through the upper mantle. However, when olivine is exposed to aqueous fluids, it adopts a more rebellious, rock star–like disposition. Here, we show that the discord, or disequilibrium, between olivine, its reaction products, and fluids containing water and carbon dioxide is so significant that it has been instrumental in changing the Earth throughout the planet’s history and will continue to do so well into the future. © 2023 Mineralogical Society of America. All rights reserved.
2808.
Magma is the Key to Sustainable Super-Hot Geothermal Energy
Volume 47
,
Page 2868 – 2882
2023
2807.
Workshop report: PlioWest -- drilling Pliocene lakes in western North America
Scientific Drilling,
3261-72
2023
2806.
Workshop on drilling the Nicaraguan lakes: bridging continents and oceans (NICA-BRIDGE)
Scientific Drilling,
3273-84
2023
2805.
Volcanosedimentary fill of the early Cretaceous Yingcheng formation and
response to the end of continental rifting in the Songliao Basin:
Constraints from well SK-2, northern Xujiaweizi fault depression
MARINE AND PETROLEUM GEOLOGY,
157
2023
Keywords:▾
Yingcheng formation; Strike-slip faulting; Songliao basin; End of
continental rifting; Early cretaceous; SK-2
2804.
Volcanic impact on terrestrial and aquatic ecosystems in the Eastern Mediterranean
Communications Earth and Environment,
4
(1)
2023