Geoff A T Duller
Dados Biográficos
| ID | 3072956 |
|---|---|
| NOME | Geoff A T Duller |
| PRENOMES | Geoff A T |
| SOBRENOME | Duller |
| ASSINATURA | DULLER G A T |
| AFILIAÇÕES | Aberystwyth University |
| ORCID | 0000-0002-2694-4590 |
| VERIFICADO | Sim |
| TOTAL DE OBRAS | 24 |
| TOTAL DE CITAÇÕES | 543 |
| TOTAL COMO AUTOR | 24 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2000 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2016 |
| ÍNDICE H | 9 |
Challenges involved in obtaining luminescence ages for long records of aridity
Drac
Developing a framework of Quaternary dune accumulation in the northern Rub' al-Khali, Arabia
Excavations at Site C North, Kalambo Falls, Zambia
We report on the results of small-scale excavations at the archaeological site of Kalambo Falls, northern Zambia. The site has long been known for its stratified succession of Stone Age horizons, in particular those representing the late Acheulean (Mode 2) and early Middle Stone Age (Mode 3). Previous efforts to date these horizons have provided, at best, minimum radiometric ages. The absence of a firm chronology for the site has limited its pote…
New investigations at Kalambo Falls, Zambia
Fluvial deposits can provide excellent archives of early hominin activity but may be complex to interpret, especially without extensive geochronology. The Stone Age site of Kalambo Falls, northern Zambia, has yielded a rich artefact record from dominantly fluvial deposits, but its significance has been restricted by uncertainties over site formation processes and a limited chronology. Our new investigations in the centre of the Kalambo Basin have…
Chronology and controls of donga (gully) formation in the upper Blood River catchment, KwaZulu-Natal, South Africa
Dongas (gullies and badland-type terrain) are found extensively across interior South Africa, but the controls on their formation remain contested. Establishing the timing of donga formation is essential for developing a clearer understanding of the relative importance of natural (e.g. climatic) and human (e.g. overgrazing) controls. Here, we present optically stimulated luminescence (OSL) ages for colluvial sediments exposed in the sidewalls of …
Fluvial landscapes of the Harappan civilization
The collapse of the Bronze Age Harappan, one of the earliest urban civilizations, remains an enigma. Urbanism flourished in the western region of the Indo-Gangetic Plain for approximately 600 y, but since approximately 3,900 y ago, the total settled area and settlement sizes declined, many sites were abandoned, and a significant shift in site numbers and density towards the east is recorded. We report morphologic and chronologic evidence indicati…
The dating and interpretation of a Mode 1 site in the Luangwa Valley, Zambia
Recent faulting in the southern Arava, Dead Sea Transform
Single‐grain optical dating of Quaternary sediments
Optical dating measures the time that has elapsed since mineral grains were exposed to daylight. The technique is ideal for sediments in which all the grains were exposed to sufficient daylight at deposition to reset the optically stimulated luminescence (OSL) signal. However, in many environments the exposure of individual grains to daylight will be variable. Limited exposure to light results in grains retaining a part of any prior trapped charg…
Glaciar León, Chilean Patagonia
Glaciar León is a temperate, grounded outlet of the eastern North Patagonian Icefield (NPI). It terminates at an active calving margin in Lago Leones, a 10 km long proglacial lake. We take a multidisciplinary approach to its description and use ASTER imagery and clast sedimentology to describe the geomorphology of the glacier and its associated moraines. We date periods of glacier retreat over the last 2500 years using a combination of lichenomet…
Equivalent dose distributions from single grains of quartz at Sibudu, South Africa
New ages for the post-Howiesons Poort, late and final Middle Stone Age at Sibudu, South Africa
Evidence from the Rio Bayo valley on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene Transition
This paper presents data on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene transition using cosmogenic nuclide exposure age and optically stimulated luminescence dating. We describe geomorphological and geochronological evidence for glacier extent in one of the major valleys surrounding the North Patagonian Icefield, the Rio Bayo valley. Geomorphological mapping provides evidence for the existence of two types of…
Extending the chronology of deposits at Blombos Cave, South Africa, back to 140ka using optical dating of single and multiple grains of quartz
Optical dating of a scroll-bar sequence on the Klip River, South Africa, to derive the lateral migration rate of a meander bend
Problems are often encountered in accurately establishing the rates of processes associated with river channel change. In this study, optical dating was used to obtain the lateral migration rate of an abandoned meander bend on the Klip River, eastern Free State, South Africa. Five samples were collected by augering along a transect across an approximately 200-m-wide scroll-bar sequence on the inner meander bend, and an additional sample was colle…
Optical dating of a Fimic Anthrosol in the southern Netherlands
Luminescence dating of quaternary sediments
Luminescence dating is unique amongst geochronological methods in dating the deposition of sediments based upon the properties of the constituent minerals. For Quaternary sediments the event being dated is the last exposure of the grains to daylight, and an implicit assumption is that this exposure was sufficient to remove any pre‐existing signal. Until recently it has been difficult to test this assumption, other than by dating samples from a gi…
Unprecedented last-glacial mass accumulation rates determined by luminescence dating of loess from western Nebraska
A high-resolution chronology for Peoria (last glacial period) Loess from three sites in Nebraska, midcontinental North America, is determined by applying optically stimulated luminescence (OSL) dating to 35–50 μm quartz. At Bignell Hill, Nebraska, an OSL age of 25,000 yr near the contact of Peoria Loess with the underlying Gilman Canyon Formation shows that dust accumulation occurred early during the last glacial maximum (LGM), whereas at Devil’s…
Distinguishing quartz and feldspar in single grain luminescence measurements
Developments in radiation, stimulation and observation facilities in luminescence measurements
Optical dating of dune sand from Blombos Cave, South Africa
Optical dating of dune sand from Blombos Cave, South Africa
Advances in luminescence instrument systems
Extending the chronology of deposits at Blombos Cave, South Africa, back to 140ka using optical dating of single and multiple grains of quartz
New ages for the post-Howiesons Poort, late and final Middle Stone Age at Sibudu, South Africa
Optical dating of dune sand from Blombos Cave, South Africa
Optical dating of dune sand from Blombos Cave, South Africa
Equivalent dose distributions from single grains of quartz at Sibudu, South Africa
New investigations at Kalambo Falls, Zambia
Fluvial deposits can provide excellent archives of early hominin activity but may be complex to interpret, especially without extensive geochronology. The Stone Age site of Kalambo Falls, northern Zambia, has yielded a rich artefact record from dominantly fluvial deposits, but its significance has been restricted by uncertainties over site formation processes and a limited chronology. Our new investigations in the centre of the Kalambo Basin have…
Excavations at Site C North, Kalambo Falls, Zambia
We report on the results of small-scale excavations at the archaeological site of Kalambo Falls, northern Zambia. The site has long been known for its stratified succession of Stone Age horizons, in particular those representing the late Acheulean (Mode 2) and early Middle Stone Age (Mode 3). Previous efforts to date these horizons have provided, at best, minimum radiometric ages. The absence of a firm chronology for the site has limited its pote…
The dating and interpretation of a Mode 1 site in the Luangwa Valley, Zambia
Optical dating of a scroll-bar sequence on the Klip River, South Africa, to derive the lateral migration rate of a meander bend
Problems are often encountered in accurately establishing the rates of processes associated with river channel change. In this study, optical dating was used to obtain the lateral migration rate of an abandoned meander bend on the Klip River, eastern Free State, South Africa. Five samples were collected by augering along a transect across an approximately 200-m-wide scroll-bar sequence on the inner meander bend, and an additional sample was colle…
Glaciar León, Chilean Patagonia
Glaciar León is a temperate, grounded outlet of the eastern North Patagonian Icefield (NPI). It terminates at an active calving margin in Lago Leones, a 10 km long proglacial lake. We take a multidisciplinary approach to its description and use ASTER imagery and clast sedimentology to describe the geomorphology of the glacier and its associated moraines. We date periods of glacier retreat over the last 2500 years using a combination of lichenomet…
Chronology and controls of donga (gully) formation in the upper Blood River catchment, KwaZulu-Natal, South Africa
Dongas (gullies and badland-type terrain) are found extensively across interior South Africa, but the controls on their formation remain contested. Establishing the timing of donga formation is essential for developing a clearer understanding of the relative importance of natural (e.g. climatic) and human (e.g. overgrazing) controls. Here, we present optically stimulated luminescence (OSL) ages for colluvial sediments exposed in the sidewalls of …
Advances in luminescence instrument systems
Unprecedented last-glacial mass accumulation rates determined by luminescence dating of loess from western Nebraska
A high-resolution chronology for Peoria (last glacial period) Loess from three sites in Nebraska, midcontinental North America, is determined by applying optically stimulated luminescence (OSL) dating to 35–50 μm quartz. At Bignell Hill, Nebraska, an OSL age of 25,000 yr near the contact of Peoria Loess with the underlying Gilman Canyon Formation shows that dust accumulation occurred early during the last glacial maximum (LGM), whereas at Devil’s…
Distinguishing quartz and feldspar in single grain luminescence measurements
Developments in radiation, stimulation and observation facilities in luminescence measurements
Optical dating of dune sand from Blombos Cave, South Africa
Optical dating of dune sand from Blombos Cave, South Africa
Luminescence dating of quaternary sediments
Luminescence dating is unique amongst geochronological methods in dating the deposition of sediments based upon the properties of the constituent minerals. For Quaternary sediments the event being dated is the last exposure of the grains to daylight, and an implicit assumption is that this exposure was sufficient to remove any pre‐existing signal. Until recently it has been difficult to test this assumption, other than by dating samples from a gi…
Optical dating of a scroll-bar sequence on the Klip River, South Africa, to derive the lateral migration rate of a meander bend
Problems are often encountered in accurately establishing the rates of processes associated with river channel change. In this study, optical dating was used to obtain the lateral migration rate of an abandoned meander bend on the Klip River, eastern Free State, South Africa. Five samples were collected by augering along a transect across an approximately 200-m-wide scroll-bar sequence on the inner meander bend, and an additional sample was colle…
Optical dating of a Fimic Anthrosol in the southern Netherlands
Evidence from the Rio Bayo valley on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene Transition
This paper presents data on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene transition using cosmogenic nuclide exposure age and optically stimulated luminescence dating. We describe geomorphological and geochronological evidence for glacier extent in one of the major valleys surrounding the North Patagonian Icefield, the Rio Bayo valley. Geomorphological mapping provides evidence for the existence of two types of…
Extending the chronology of deposits at Blombos Cave, South Africa, back to 140ka using optical dating of single and multiple grains of quartz
Single‐grain optical dating of Quaternary sediments
Optical dating measures the time that has elapsed since mineral grains were exposed to daylight. The technique is ideal for sediments in which all the grains were exposed to sufficient daylight at deposition to reset the optically stimulated luminescence (OSL) signal. However, in many environments the exposure of individual grains to daylight will be variable. Limited exposure to light results in grains retaining a part of any prior trapped charg…
Glaciar León, Chilean Patagonia
Glaciar León is a temperate, grounded outlet of the eastern North Patagonian Icefield (NPI). It terminates at an active calving margin in Lago Leones, a 10 km long proglacial lake. We take a multidisciplinary approach to its description and use ASTER imagery and clast sedimentology to describe the geomorphology of the glacier and its associated moraines. We date periods of glacier retreat over the last 2500 years using a combination of lichenomet…
Equivalent dose distributions from single grains of quartz at Sibudu, South Africa
New ages for the post-Howiesons Poort, late and final Middle Stone Age at Sibudu, South Africa
Recent faulting in the southern Arava, Dead Sea Transform
The dating and interpretation of a Mode 1 site in the Luangwa Valley, Zambia
Fluvial landscapes of the Harappan civilization
The collapse of the Bronze Age Harappan, one of the earliest urban civilizations, remains an enigma. Urbanism flourished in the western region of the Indo-Gangetic Plain for approximately 600 y, but since approximately 3,900 y ago, the total settled area and settlement sizes declined, many sites were abandoned, and a significant shift in site numbers and density towards the east is recorded. We report morphologic and chronologic evidence indicati…
Chronology and controls of donga (gully) formation in the upper Blood River catchment, KwaZulu-Natal, South Africa
Dongas (gullies and badland-type terrain) are found extensively across interior South Africa, but the controls on their formation remain contested. Establishing the timing of donga formation is essential for developing a clearer understanding of the relative importance of natural (e.g. climatic) and human (e.g. overgrazing) controls. Here, we present optically stimulated luminescence (OSL) ages for colluvial sediments exposed in the sidewalls of …
Drac
Developing a framework of Quaternary dune accumulation in the northern Rub' al-Khali, Arabia
Excavations at Site C North, Kalambo Falls, Zambia
We report on the results of small-scale excavations at the archaeological site of Kalambo Falls, northern Zambia. The site has long been known for its stratified succession of Stone Age horizons, in particular those representing the late Acheulean (Mode 2) and early Middle Stone Age (Mode 3). Previous efforts to date these horizons have provided, at best, minimum radiometric ages. The absence of a firm chronology for the site has limited its pote…
New investigations at Kalambo Falls, Zambia
Fluvial deposits can provide excellent archives of early hominin activity but may be complex to interpret, especially without extensive geochronology. The Stone Age site of Kalambo Falls, northern Zambia, has yielded a rich artefact record from dominantly fluvial deposits, but its significance has been restricted by uncertainties over site formation processes and a limited chronology. Our new investigations in the centre of the Kalambo Basin have…
Challenges involved in obtaining luminescence ages for long records of aridity
Geology and Paleoclimatology Research (22 obras) · Geography (17 obras) · Archaeology (15 obras) · Geology (15 obras) · Paleontology (13 obras) · Geology (12 obras) · Paleontology (10 obras) · Thermoluminescence dating (10 obras) · Archaeology and ancient environmental studies (9 obras) · Pleistocene (9 obras)