Dataset Information

Archaean and Proterozoic diamond growth from contrasting styles of large-scale magmatism.

ABSTRACT: Precise dating of diamond growth is required to understand the interior workings of the early Earth and the deep carbon cycle. Here we report Sm-Nd isotope data from 26 individual garnet inclusions from 26 harzburgitic diamonds from Venetia, South Africa. Garnet inclusions and host diamonds comprise two compositional suites formed under markedly different conditions and define two isochrons, one Archaean (2.95?Ga) and one Proterozoic (1.15?Ga). The Archaean diamond suite formed from relatively cool fluid-dominated metasomatism during rifting of the southern shelf of the Zimbabwe Craton. The 1.8 billion years younger Proterozoic diamond suite formed by melt-dominated metasomatism related to the 1.1?Ga Umkondo Large Igneous Province. The results demonstrate that resolving the time of diamond growth events requires dating of individual inclusions, and that there was a major change in the magmatic processes responsible for harzburgitic diamond formation beneath Venetia from the Archaean to the Proterozoic.Dating of inclusions within diamonds is used to reconstruct Earth's geodynamic history. Here, the authors report isotope data on individual garnet inclusions within diamonds from Venetia, South Africa, showing that two suites of diamonds define two isochrons, showing the importance of dating individual inclusions.

SUBMITTER: Koornneef JM

PROVIDER: S-EPMC5608721 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Archaean and Proterozoic diamond growth from contrasting styles of large-scale magmatism.

Koornneef Janne M JM Gress Michael U MU Chinn Ingrid L IL Jelsma Hielke A HA Harris Jeff W JW Davies Gareth R GR

Nature communications 20170921 1

Precise dating of diamond growth is required to understand the interior workings of the early Earth and the deep carbon cycle. Here we report Sm-Nd isotope data from 26 individual garnet inclusions from 26 harzburgitic diamonds from Venetia, South Africa. Garnet inclusions and host diamonds comprise two compositional suites formed under markedly different conditions and define two isochrons, one Archaean (2.95 Ga) and one Proterozoic (1.15 Ga). The Archaean diamond suite formed from relatively c ...[more]

PMID: 28935863

Similar Datasets

Project description:During angiogenesis, growing neovessels must effectively navigate through the tissue space as they elongate and subsequently integrate into a microvascular network. While time series microscopy has provided insight into the cell activities within single growing neovessel sprouts, less is known concerning neovascular dynamics within a large angiogenic tissue bed. Here, we developed a time-lapse imaging technique that allowed visualization and quantification of sprouting neovessels as they form and grow away from adult parent microvessels in three dimensions over cubic millimeters of matrix volume during the course of up to 5 days on the microscope. Using a new image acquisition procedure and novel morphometric analysis tools, we quantified the elongation dynamics of growing neovessels and found an episodic growth pattern accompanied by fluctuations in neovessel diameter. Average elongation rate was 5 ?m/h for individual vessels, but we also observed considerable dynamic variability in growth character including retraction and complete regression of entire neovessels. We observed neovessel-to-neovessel directed growth over tens to hundreds of microns preceding tip-to-tip inosculation. As we have previously described via static 3D imaging at discrete time points, we identified different collagen fibril structures associated with the growing neovessel tip and stalk, and observed the coordinated alignment of growing neovessels in a deforming matrix. Overall analysis of the entire image volumes demonstrated that although individual neovessels exhibited episodic growth and regression, there was a monotonic increase in parameters associated with the entire vascular bed such as total network length and number of branch points. This new time-lapse imaging approach corroborated morphometric changes in individual neovessels described by us and others, as well as captured dynamic neovessel behaviors unique to days-long angiogenesis within the forming neovascular network.

Dataset Information

Archaean and Proterozoic diamond growth from contrasting styles of large-scale magmatism.

Publications

Archaean and Proterozoic diamond growth from contrasting styles of large-scale magmatism.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets