J Hellstrom
Dados Biográficos
| ID | 4020878 |
|---|---|
| NOME | J Hellstrom |
| PRENOMES | J |
| SOBRENOME | Hellstrom |
| ASSINATURA | HELLSTROM J |
| AFILIAÇÕES | The University of Melbourne |
| ORCID | 0000-0001-9427-3525 |
| VERIFICADO | Sim |
| TOTAL DE OBRAS | 15 |
| TOTAL DE CITAÇÕES | 37 |
| TOTAL COMO AUTOR | 15 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2006 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2024 |
| ÍNDICE H | 4 |
Tropical vegetation productivity and atmospheric methane over the last 40,000 years from model simulations and stalagmites in Sulawesi, Indonesia
Recent research has shown the potential of speleothem δ 13 C to record a range of environmental processes. Here, we report on 230 Th-dated stalagmite δ 13 C records for southwest Sulawesi, Indonesia, over the last 40,000 yr to investigate the relationship between tropical vegetation productivity and atmospheric methane concentrations. We demonstrate that the Sulawesi stalagmite δ 13 C record is driven by changes in vegetation productivity and soi…
High-resolution reconstruction of infiltration in the Southern Cook Islands based on trace elements in speleothems
This study utilizes speleothem trace elements as climate proxies to reconstruct hydroclimate variability over approximately 350 years in the Southern Cook Islands. Stalagmites Pu17 and Pu4 from Pouatea cave were analyzed using high-resolution LA-ICP-MS for trace elements (Mg, Na, Sr, P, U, Y). By monitoring cave dripwater and conducting regression analysis, we found that Mg, Sr, and Na in Pouatea dripwater mostly originated from marine aerosols, …
Improving the age constraints on the archeological record in Scladina Cave (Belgium)
The sedimentary sequence in Scladina Cave (Belgium) is well-known for its rich Middle Paleolithic assemblages and its numerous faunal remains. Of particular interest is the presence of a nearly complete mandible of a Neandertal child. To place all these finds in the correct chronostratigraphic context, various dating techniques have been applied over the past decades. This resulted in a reasonably well-constrained age model, roughly spanning the …
Holocene hydroclimate changes in continental Croatia recorded in speleothem δ 13 C and δ 18 O from Nova Grgosova Cave
We present the first stable isotope (δ 13 C and δ 18 O) speleothem record from continental Croatia retrieved from two coeval stalagmites from Nova Grgosova Cave. U-Th dates constrain the stalagmite growth history from 10 ka to the present, revealing coeval growth between 7.8 and 5.6 ka. We interpret δ 18 O as an autumn/winter hydrological proxy related to changes of vapor source, precipitation amount, and/or seasonal rainfall distribution, while …
Contemporaneity of Australopithecus , Paranthropus , and early Homo erectus in South Africa
Dating the Drimolen hominins Fossil hominins from South Africa are enriching the story of early human evolution and dispersal. Herries et al. describe the geological context and dating of the hominin-bearing infilled cave, or palaeocave, at a site called Drimolen in South Africa (see the Perspective by Antón). They focus on the age and context of a recently discovered Homo erectus sensu lato fossil and a Paranthropus robustus fossil, which they d…
Late-Holocene environmental change on the Nullarbor Plain, southwest Australia, based on speleothem pollen records
Fossil pollen from two stalagmites is examined to reconstruct a c. 2400-year history of vegetation change on the Nullarbor Plain. Environmental changes are reflected by variation in chenopod species abundance, and by a peak in woody taxa between 1000 and 800 years ago which is interpreted as evidence of increased moisture conditions associated with a positive phase of the Southern Annular Mode. While no strong palynological signal is observed at …
The age of Homo naledi and associated sediments in the Rising Star Cave, South Africa
New ages for flowstone, sediments and fossil bones from the Dinaledi Chamber are presented. We combined optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones to establish that all sediments containing Homo naledi fossils can be allocated to a single stratigraphic entity (sub-unit 3b), interpreted to be deposited between 236 ka and 414 ka. This result has been confirmed independently by dating th…
Recent advances and future prospects of the U–Th and U–Pb chronometers applicable to archaeology
The Neanderthal in the karst
A continuous stable isotope record from the penultimate glacial maximum to the Last Interglacial (159–121 ka) from Tana Che Urla Cave (Apuan Alps, central Italy)
Relatively few radiometrically dated records are available for the central Mediterranean spanning the marine oxygen isotope stage 6–5 (MIS 6–5) transition and the first part of the Last Interglacial. Two flowstone cores from Tana che Urla Cave (TCU, central Italy), constrained by 19 U/Th ages, preserve an interval of continuous speleothem deposition between ca. 159 and 121 ka. A multiproxy record (δ 18 O, δ 13 C, growth rate and petrographic chan…
Australopithecus sediba at 1.977 Ma and Implications for the Origins of the Genus Homo
Further U-series dating and the magnetic stratigraphy of the hosting cave deposits show that Australopithecus sediba lived just under 2 million years ago, near or just before the emergence of Homo .
Dating the Lascaux Cave Gour Formation
Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flowstone that covered a large part of the cave until its opening for tourists during the 1950s. The deposit comprises a succession of calcite rims, or “gours,” which allowed seepage water to pond in large areas in the cave. Their possible…
Holocene climate change in arid Australia from speleothem and alluvial records
New high-resolution MC-ICPMS U/Th ages and C and O isotopic analyses from a Holocene speleothem in arid south-central Australia provide evidence for increased effective precipitation (EP) relative to present at c. 11.5 ka and c. 8—5 ka, peak moisture at 7—6 ka, and onset of an arid climate similar to present by c. 5 ka. δ 18 O and δ 13 C time-series data exhibit marked (>+1‰) contemporaneous excursions over base-line values of −5.3‰ and −11.0‰, r…
Late Holocene drought responsible for the collapse of Old World civilizations is recorded in an Italian cave flowstone
A severe drought in parts of low-latitude northeastern Africa and southwestern Asia\n\nca 4200 yr ago caused major disruption to ancient civilizations. Stable isotope, trace element,\n\nand organic fluorescence data from a calcite flowstone collected from the wellwatered\n\nAlpi Apuane karst of central-western Italy indicate that the climatic event responsible\n\nfor this drought was also recorded in mid-latitude Europe. Although the timing\n\nof…
Author response
Article Figures and data Abstract eLife digest Introduction Results Discussion Material and methods References Decision letter Author response Article and author information Metrics Abstract New ages for flowstone, sediments and fossil bones from the Dinaledi Chamber are presented. We combined optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones to establish that all sediments containing Homo n…
The Neanderthal in the karst
Recent advances and future prospects of the U–Th and U–Pb chronometers applicable to archaeology
Holocene climate change in arid Australia from speleothem and alluvial records
New high-resolution MC-ICPMS U/Th ages and C and O isotopic analyses from a Holocene speleothem in arid south-central Australia provide evidence for increased effective precipitation (EP) relative to present at c. 11.5 ka and c. 8—5 ka, peak moisture at 7—6 ka, and onset of an arid climate similar to present by c. 5 ka. δ 18 O and δ 13 C time-series data exhibit marked (>+1‰) contemporaneous excursions over base-line values of −5.3‰ and −11.0‰, r…
Dating the Lascaux Cave Gour Formation
Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flowstone that covered a large part of the cave until its opening for tourists during the 1950s. The deposit comprises a succession of calcite rims, or “gours,” which allowed seepage water to pond in large areas in the cave. Their possible…
Author response
Article Figures and data Abstract eLife digest Introduction Results Discussion Material and methods References Decision letter Author response Article and author information Metrics Abstract New ages for flowstone, sediments and fossil bones from the Dinaledi Chamber are presented. We combined optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones to establish that all sediments containing Homo n…
Holocene hydroclimate changes in continental Croatia recorded in speleothem δ 13 C and δ 18 O from Nova Grgosova Cave
We present the first stable isotope (δ 13 C and δ 18 O) speleothem record from continental Croatia retrieved from two coeval stalagmites from Nova Grgosova Cave. U-Th dates constrain the stalagmite growth history from 10 ka to the present, revealing coeval growth between 7.8 and 5.6 ka. We interpret δ 18 O as an autumn/winter hydrological proxy related to changes of vapor source, precipitation amount, and/or seasonal rainfall distribution, while …
Late Holocene drought responsible for the collapse of Old World civilizations is recorded in an Italian cave flowstone
A severe drought in parts of low-latitude northeastern Africa and southwestern Asia\n\nca 4200 yr ago caused major disruption to ancient civilizations. Stable isotope, trace element,\n\nand organic fluorescence data from a calcite flowstone collected from the wellwatered\n\nAlpi Apuane karst of central-western Italy indicate that the climatic event responsible\n\nfor this drought was also recorded in mid-latitude Europe. Although the timing\n\nof…
Holocene climate change in arid Australia from speleothem and alluvial records
New high-resolution MC-ICPMS U/Th ages and C and O isotopic analyses from a Holocene speleothem in arid south-central Australia provide evidence for increased effective precipitation (EP) relative to present at c. 11.5 ka and c. 8—5 ka, peak moisture at 7—6 ka, and onset of an arid climate similar to present by c. 5 ka. δ 18 O and δ 13 C time-series data exhibit marked (>+1‰) contemporaneous excursions over base-line values of −5.3‰ and −11.0‰, r…
Australopithecus sediba at 1.977 Ma and Implications for the Origins of the Genus Homo
Further U-series dating and the magnetic stratigraphy of the hosting cave deposits show that Australopithecus sediba lived just under 2 million years ago, near or just before the emergence of Homo .
Dating the Lascaux Cave Gour Formation
Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flowstone that covered a large part of the cave until its opening for tourists during the 1950s. The deposit comprises a succession of calcite rims, or “gours,” which allowed seepage water to pond in large areas in the cave. Their possible…
A continuous stable isotope record from the penultimate glacial maximum to the Last Interglacial (159–121 ka) from Tana Che Urla Cave (Apuan Alps, central Italy)
Relatively few radiometrically dated records are available for the central Mediterranean spanning the marine oxygen isotope stage 6–5 (MIS 6–5) transition and the first part of the Last Interglacial. Two flowstone cores from Tana che Urla Cave (TCU, central Italy), constrained by 19 U/Th ages, preserve an interval of continuous speleothem deposition between ca. 159 and 121 ka. A multiproxy record (δ 18 O, δ 13 C, growth rate and petrographic chan…
Recent advances and future prospects of the U–Th and U–Pb chronometers applicable to archaeology
The Neanderthal in the karst
The age of Homo naledi and associated sediments in the Rising Star Cave, South Africa
New ages for flowstone, sediments and fossil bones from the Dinaledi Chamber are presented. We combined optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones to establish that all sediments containing Homo naledi fossils can be allocated to a single stratigraphic entity (sub-unit 3b), interpreted to be deposited between 236 ka and 414 ka. This result has been confirmed independently by dating th…
Contemporaneity of Australopithecus , Paranthropus , and early Homo erectus in South Africa
Dating the Drimolen hominins Fossil hominins from South Africa are enriching the story of early human evolution and dispersal. Herries et al. describe the geological context and dating of the hominin-bearing infilled cave, or palaeocave, at a site called Drimolen in South Africa (see the Perspective by Antón). They focus on the age and context of a recently discovered Homo erectus sensu lato fossil and a Paranthropus robustus fossil, which they d…
Late-Holocene environmental change on the Nullarbor Plain, southwest Australia, based on speleothem pollen records
Fossil pollen from two stalagmites is examined to reconstruct a c. 2400-year history of vegetation change on the Nullarbor Plain. Environmental changes are reflected by variation in chenopod species abundance, and by a peak in woody taxa between 1000 and 800 years ago which is interpreted as evidence of increased moisture conditions associated with a positive phase of the Southern Annular Mode. While no strong palynological signal is observed at …
Holocene hydroclimate changes in continental Croatia recorded in speleothem δ 13 C and δ 18 O from Nova Grgosova Cave
We present the first stable isotope (δ 13 C and δ 18 O) speleothem record from continental Croatia retrieved from two coeval stalagmites from Nova Grgosova Cave. U-Th dates constrain the stalagmite growth history from 10 ka to the present, revealing coeval growth between 7.8 and 5.6 ka. We interpret δ 18 O as an autumn/winter hydrological proxy related to changes of vapor source, precipitation amount, and/or seasonal rainfall distribution, while …
Tropical vegetation productivity and atmospheric methane over the last 40,000 years from model simulations and stalagmites in Sulawesi, Indonesia
Recent research has shown the potential of speleothem δ 13 C to record a range of environmental processes. Here, we report on 230 Th-dated stalagmite δ 13 C records for southwest Sulawesi, Indonesia, over the last 40,000 yr to investigate the relationship between tropical vegetation productivity and atmospheric methane concentrations. We demonstrate that the Sulawesi stalagmite δ 13 C record is driven by changes in vegetation productivity and soi…
High-resolution reconstruction of infiltration in the Southern Cook Islands based on trace elements in speleothems
This study utilizes speleothem trace elements as climate proxies to reconstruct hydroclimate variability over approximately 350 years in the Southern Cook Islands. Stalagmites Pu17 and Pu4 from Pouatea cave were analyzed using high-resolution LA-ICP-MS for trace elements (Mg, Na, Sr, P, U, Y). By monitoring cave dripwater and conducting regression analysis, we found that Mg, Sr, and Na in Pouatea dripwater mostly originated from marine aerosols, …
Author response
Article Figures and data Abstract eLife digest Introduction Results Discussion Material and methods References Decision letter Author response Article and author information Metrics Abstract New ages for flowstone, sediments and fossil bones from the Dinaledi Chamber are presented. We combined optically stimulated luminescence dating of sediments with U-Th and palaeomagnetic analyses of flowstones to establish that all sediments containing Homo n…
Improving the age constraints on the archeological record in Scladina Cave (Belgium)
The sedimentary sequence in Scladina Cave (Belgium) is well-known for its rich Middle Paleolithic assemblages and its numerous faunal remains. Of particular interest is the presence of a nearly complete mandible of a Neandertal child. To place all these finds in the correct chronostratigraphic context, various dating techniques have been applied over the past decades. This resulted in a reasonably well-constrained age model, roughly spanning the …
Cave (13 obras) · Geography (13 obras) · Archaeology (12 obras) · Geology and Paleoclimatology Research (11 obras) · Geology (8 obras) · Pleistocene-Era Hominins and Archaeology (8 obras) · Speleothem (8 obras) · Geology (6 obras) · Holocene (6 obras) · Paleontology (6 obras)