Optically stimulated and thermoluminescence ages from relict shorelines, along with accelerator m... more Optically stimulated and thermoluminescence ages from relict shorelines, along with accelerator mass spectrometer 14C ages from freshwater molluscs reveal a record of variable moisture sources supplied by northern and southern river systems to Lake Mega-Frome in southern central Australia during the late Quaternary.
In previous work the conventional SAR procedure has been demonstrated to work well for a large nu... more In previous work the conventional SAR procedure has been demonstrated to work well for a large number of samples.
Recent development of an instrument for measuring the optically stimulated luminescence signal fr... more Recent development of an instrument for measuring the optically stimulated luminescence signal from individual mineral grains has made it practicable to measure the equivalent dose (De) from many hundreds or thousands of single mineral grains from a sample. Such measurements can potentially be used to address issues such as sample integrity, and to make it possible to obtain ages from samples that consist of mixtures of grains, enlarging the range of materials to which luminescence dating can be applied.
A sequence of optically stimulated luminescence measurements was made on each of 8,961 grains fro... more A sequence of optically stimulated luminescence measurements was made on each of 8,961 grains from three sand samples from Blombos on the southern Cape coast. One sand unit overlay Middle Stone Age deposits in Blombos Cave. The measurement sequence, the single aliquot regenerative dose protocol, was used to obtain values for the total effective radiation dose to which each grain had been exposed since burial.
Abstract The conceptual ability to source, combine, and store substances that enhance technology ... more Abstract The conceptual ability to source, combine, and store substances that enhance technology or social practices represents a benchmark in the evolution of complex human cognition. Excavations in 2008 at Blombos Cave, South Africa, revealed a processing workshop where a liquefied ochre-rich mixture was produced and stored in two Haliotis midae (abalone) shells 100,000 years ago. Ochre, bone, charcoal, grindstones, and hammerstones form a composite part of this production toolkit.
There is consensus that the modern human lineage appeared in Africa before 100,000 years ago 1, 2... more There is consensus that the modern human lineage appeared in Africa before 100,000 years ago 1, 2. But there is debate as to when cultural and cognitive characteristics typical of modern humans first appeared, and the role that these had in the expansion of modern humans out of Africa 3. Scientists rely on symbolically specific proxies, such as artistic expression, to document the origins of complex cognition.
ABSTRACT New excavations at Contrebandiers Cave, Morocco, began in 2007 and continued through 201... more ABSTRACT New excavations at Contrebandiers Cave, Morocco, began in 2007 and continued through 2010. This site, originally excavated by Roche in the 1950s, contained deposits with Aterian, Iberomaurusian, and Neolithic materials, although the latter were completely removed during Roche's excavations.
Optically stimulated and thermoluminescence ages from relict shorelines, along with accelerator m... more Optically stimulated and thermoluminescence ages from relict shorelines, along with accelerator mass spectrometer 14C ages from freshwater molluscs reveal a record of variable moisture sources supplied by northern and southern river systems to Lake Mega-Frome in southern central Australia during the late Quaternary.
In previous work the conventional SAR procedure has been demonstrated to work well for a large nu... more In previous work the conventional SAR procedure has been demonstrated to work well for a large number of samples.
Recent development of an instrument for measuring the optically stimulated luminescence signal fr... more Recent development of an instrument for measuring the optically stimulated luminescence signal from individual mineral grains has made it practicable to measure the equivalent dose (De) from many hundreds or thousands of single mineral grains from a sample. Such measurements can potentially be used to address issues such as sample integrity, and to make it possible to obtain ages from samples that consist of mixtures of grains, enlarging the range of materials to which luminescence dating can be applied.
A sequence of optically stimulated luminescence measurements was made on each of 8,961 grains fro... more A sequence of optically stimulated luminescence measurements was made on each of 8,961 grains from three sand samples from Blombos on the southern Cape coast. One sand unit overlay Middle Stone Age deposits in Blombos Cave. The measurement sequence, the single aliquot regenerative dose protocol, was used to obtain values for the total effective radiation dose to which each grain had been exposed since burial.
Abstract The conceptual ability to source, combine, and store substances that enhance technology ... more Abstract The conceptual ability to source, combine, and store substances that enhance technology or social practices represents a benchmark in the evolution of complex human cognition. Excavations in 2008 at Blombos Cave, South Africa, revealed a processing workshop where a liquefied ochre-rich mixture was produced and stored in two Haliotis midae (abalone) shells 100,000 years ago. Ochre, bone, charcoal, grindstones, and hammerstones form a composite part of this production toolkit.
There is consensus that the modern human lineage appeared in Africa before 100,000 years ago 1, 2... more There is consensus that the modern human lineage appeared in Africa before 100,000 years ago 1, 2. But there is debate as to when cultural and cognitive characteristics typical of modern humans first appeared, and the role that these had in the expansion of modern humans out of Africa 3. Scientists rely on symbolically specific proxies, such as artistic expression, to document the origins of complex cognition.
ABSTRACT New excavations at Contrebandiers Cave, Morocco, began in 2007 and continued through 201... more ABSTRACT New excavations at Contrebandiers Cave, Morocco, began in 2007 and continued through 2010. This site, originally excavated by Roche in the 1950s, contained deposits with Aterian, Iberomaurusian, and Neolithic materials, although the latter were completely removed during Roche's excavations.
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