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Full-Text Articles in Life Sciences
Equivalent Dose Distributions From Single Grains Of Quartz At Sibudu, South Africa: Context, Causes And Consequences For Optical Dating Of Archaeological Deposits, Richard Roberts, Zenobia Jacobs, Geoffrey Duller, Ann Wintle
Equivalent Dose Distributions From Single Grains Of Quartz At Sibudu, South Africa: Context, Causes And Consequences For Optical Dating Of Archaeological Deposits, Richard Roberts, Zenobia Jacobs, Geoffrey Duller, Ann Wintle
Richard G Roberts
No abstract provided.
An Improved Osl Chronology For The Still Bay Layers At Blombos Cave, South Africa: Further Tests Of Single-Grain Dating Procedures And A Re-Evaluation Of The Timing Of The Still Bay Industry Across Southern Africa, Zenobia Jacobs, Elspeth Hayes, Richard Roberts, Rex Galbraith, Christopher Henshilwood
An Improved Osl Chronology For The Still Bay Layers At Blombos Cave, South Africa: Further Tests Of Single-Grain Dating Procedures And A Re-Evaluation Of The Timing Of The Still Bay Industry Across Southern Africa, Zenobia Jacobs, Elspeth Hayes, Richard Roberts, Rex Galbraith, Christopher Henshilwood
Richard G Roberts
This paper presents a series of new single-grain optically stimulated luminescence (OSL) ages for the Still Bay at Blombos Cave, South Africa, and compares them to previously published OSL, thermoluminescence (TL) and electron-spin resonance (ESR) ages for this site. Details are provided about the measurement and analytical procedures, including a discussion of the characteristics of the OSL signals of individual quartz grains. This forms the basis for further investigations into the sensitivity of the equivalent dose (De) estimates to a range of different analytical approaches, including changes in the size of the test dose, the choice of signal integration interval, …
Natural Variations In The Properties Of Tl And Irsl Emissions From Metamorphic And Volcanic K-Feldspars From East Africa: Assessing Their Reliability For Dating, L Gliganic, Richard Roberts, Z Jacobs
Natural Variations In The Properties Of Tl And Irsl Emissions From Metamorphic And Volcanic K-Feldspars From East Africa: Assessing Their Reliability For Dating, L Gliganic, Richard Roberts, Z Jacobs
Richard G Roberts
The elevated temperature infrared stimulated luminescence (IRSL) and post-IR IRSL signals of potassium (K)-feldspars have recently garnered attention for their minimal rates of anomalous fading. The post-IR IRSL signal has been used to obtain age estimates for geological deposits, mostly in Europe. Studies on the behaviour of the IRSL and post-IR IRSL signals of K-feldspars from a wider range of geographic regions and depositional contexts are needed, particularly for regions where the OSL signal from quartz is poorly behaved. Discrepancies in the literature regarding the behaviours of the IRSL and TL signals of K-feldspars also highlight the need to characterise …
Catalysts For Stone Age Innovations: What Might Have Triggered Two Short-Lived Bursts Of Technological And Behavioral Innovation In Southern Africa During The Middle Stone Age?, Richard Roberts, Zenobia Jacobs
Catalysts For Stone Age Innovations: What Might Have Triggered Two Short-Lived Bursts Of Technological And Behavioral Innovation In Southern Africa During The Middle Stone Age?, Richard Roberts, Zenobia Jacobs
Richard G Roberts
No abstract provided.
Single-Grain Osl Chronologies For Middle Palaeolithic Deposits At El Mnasra And El Harhoura 2, Morocco: Implications For Late Pleistocene Human-Environment Interactions Along The Atlantic Coast Of Northwest Africa, Zenobia Jacobs, Richard Roberts, Roland Nespoulet, M El Hajraoui, Andre Debenath
Single-Grain Osl Chronologies For Middle Palaeolithic Deposits At El Mnasra And El Harhoura 2, Morocco: Implications For Late Pleistocene Human-Environment Interactions Along The Atlantic Coast Of Northwest Africa, Zenobia Jacobs, Richard Roberts, Roland Nespoulet, M El Hajraoui, Andre Debenath
Richard G Roberts
Optically stimulated luminescence (OSL) measurements were made on individual, sand-sized grains of quartz from Middle Palaeolithic deposits at two cave sites (El Harhoura 2 and El Mnasra) on the Atlantic coast of Morocco. We were able to calculate OSL ages for 32 of the 33 samples collected from the Middle Palaeolithic deposits, including the earliest and latest Aterian levels at both sites. These ages reveal periods of occupation between about 110 and 95 ka (thousands of years ago), and at ~75 ka. A late Middle Palaeolithic occupation of El Harhoura 2 is also recorded at ~55 ka. Our single-grain OSL …