Abstract:
:Kalka is one of about 14 major layered mafic-ultramafic intrusions forming the Giles Complex in central Australia1. The stratigraphical section of the Kalka Intrusion passes from a basal pyroxenite zone (450 + m) through norite and olivine gabbro zones (3,500 m) to an uppermost anorthosite zone (800 + m)2. Further resolution into 21 cyclic units is derived from repeated mineral crystallization sequences and cyclical variation in plagioclase and olivine compositions. A conventional interpretation would have a basaltic magma progressively fractionating as crystallization proceeded from mafic base to leucocratic top, with periodic resetting to less evolved states by fresh incursions of primary magma or by convectional overturn within a sealed magma chamber. However, the reconnaissance isotopic data reported here indicate development of a more complex open system. High initial 87Sr/86Sr ratios in conjunction with normal 143Nd/144Nd ratios demonstrate massive contamination by country rock within the main part of the intrusion3. Furthermore, great variation in Sr initial ratios from 0.7049 to 0.7088 suggests substantial changes in magma composition beyond those induced by fractionation. Similar isotopic heterogeneity in the Newer Gabbros of Scotland4 and the Bushveld Complex5 has been attributed to variable contamination or the emplacement of magma batches of differing composition.
journal_name
Naturejournal_title
Natureauthors
Gray CM,Goode ADTdoi
10.1038/294155a0subject
Has Abstractpub_date
1981-11-12 00:00:00pages
155-157issue
5837eissn
0028-0836issn
1476-4687pii
294155a0journal_volume
294pub_type
杂志文章相关文献
NATURE文献大全abstract::The T-cell receptor is a cell surface heterodimer consisting of an alpha and a beta chain that binds foreign antigen in the context of a cell surface molecule encoded by the major histocompatibility complex (MHC), thus restricting the T-cell response to the surface of antigen presenting cells. The variable (V) domain ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/324679a0
更新日期:1986-12-18 00:00:00
abstract::p60src, the transforming protein of Rous sarcoma virus (RSV), is a protein kinase that has a strict specificity for tyrosine. The phosphorylation of cellular proteins by p60src (ref. 4) results in transformation. Recently, Barker and Dayhoff discovered that residues 259-485 of p60src have 22% sequence identity with re...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/310589a0
更新日期:1984-08-16 00:00:00
abstract::T-cell lines established from individuals infected with human T-cell leukaemia virus (HTLV) or generated by co-cultivation of normal human T cells with HTLV-infected T-cells, express class II (HLA-D/DR or Ia) antigens of the major histocompatibility complex (MHC) and interleukin-2 (IL-2) receptors. Because the express...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/312275a0
更新日期:1984-11-15 00:00:00
abstract::We have designed a bacterial system that is switched between different states by red light. The system consists of a synthetic sensor kinase that allows a lawn of bacteria to function as a biological film, such that the projection of a pattern of light on to the bacteria produces a high-definition (about 100 megapixel...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature04405
更新日期:2005-11-24 00:00:00
abstract::The mechanistic Target of Rapamycin Complex 1 (mTORC1) is a major regulator of eukaryotic growth that coordinates anabolic and catabolic cellular processes with inputs such as growth factors and nutrients, including amino acids. In mammals arginine is particularly important, promoting diverse physiological effects suc...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature19079
更新日期:2016-08-11 00:00:00
abstract::A review of fossil mammalian faunas from the Middle Awash indicates they span most of the later Neogene and document evolutionary change in several mammalian groups, especially Primates, Proboscidea and Artiodactyla. Oldowan artefacts first appear in the late Pliocene, while Acheulian and later industries and apparent...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/298025a0
更新日期:1982-07-01 00:00:00
abstract::Modification of tyrosine residues of proteins has attracted great interest. Although phosphorylation has received most attention, tyrosine-O-sulphation is also common and has been closely investigated in the hormones gastrin and cholecystokinin (CCK). CCK regulates pancreatic enzyme secretion. It is always sulphated a...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/309456a0
更新日期:1984-05-31 00:00:00
abstract::Memory is believed to depend on activity-dependent changes in the strength of synapses. In part, this view is based on evidence that the efficacy of synapses can be enhanced or depressed depending on the timing of pre- and postsynaptic activity. However, when such plastic synapses are incorporated into neural network ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature01530
更新日期:2003-04-03 00:00:00
abstract::Stable associations of more than one species of symbiont within a single host cell or tissue are assumed to be rare in metazoans because competition for space and resources between symbionts can be detrimental to the host. In animals with multiple endosymbionts, such as mussels from deep-sea hydrothermal vents and ree...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/35077067
更新日期:2001-05-17 00:00:00
abstract::Cysticercosis caused by larval tapeworms is a major public health problem and a cause of substantial economic losses in the farm-animal industries. Taenia ovis in sheep is a particularly important example. Immunity to reinfection with the larvae has a central role in regulating natural transmission of the parasites, a...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/338585a0
更新日期:1989-04-13 00:00:00
abstract::Haploids and double haploids are important resources for studying recessive traits and have large impacts on crop breeding, but natural haploids are rare in animals. Mammalian haploids are restricted to germline cells and are occasionally found in tumours with massive chromosome loss. Recent success in establishing ha...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature11435
更新日期:2012-10-18 00:00:00
abstract::The fundus of the guinea-pig stomach actively dilates in response to low increases in intragastric pressure. This physiological response, now called adaptive relaxation, accommodates the intake of liquid or food. It is independent of external innervation, resistant to ganglion blockade, but reflex in origin. The nerve...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/351477a0
更新日期:1991-06-06 00:00:00
abstract::Hypermethylation of the promoters of tumour suppressor genes represses transcription of these genes, conferring growth advantages to cancer cells. How these changes arise is poorly understood. Here we show that the activity of oxygen-dependent ten-eleven translocation (TET) enzymes is reduced by tumour hypoxia in huma...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature19081
更新日期:2016-09-01 00:00:00
abstract::In their investigation into whether female mate-choice drives male dispersal, Höner et al. argue that female spotted hyaenas (Crocuta crocuta) prefer mates whose tenure in the social group is less than the females' age, to avoid paternal incest, and suggest that male dispersal reflects this preference. However, we are...
journal_title:Nature
pub_type: 评论,杂志文章
doi:10.1038/nature07122
更新日期:2008-07-10 00:00:00
abstract::Since the discovery of graphene, the family of two-dimensional materials has grown, displaying a broad range of electronic properties. Recent additions include semiconductors with spin-valley coupling, Ising superconductors that can be tuned into a quantum metal, possible Mott insulators with tunable charge-density wa...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature22391
更新日期:2017-06-07 00:00:00
abstract::Gram-negative bacteria, such as Escherichia coli, expel toxic chemicals through tripartite efflux pumps that span both the inner and outer membrane. The three parts are an inner membrane, substrate-binding transporter; a membrane fusion protein; and an outer-membrane-anchored channel. The fusion protein connects the t...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature09743
更新日期:2011-02-24 00:00:00
abstract::In the course of synaptic transmission in the brain and periphery, acetylcholine receptors (AChRs) rapidly transduce a chemical signal into an electrical impulse. The speed of transduction is facilitated by rapid ACh association and dissociation, suggesting a binding site relatively non-selective for small cations. Se...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature07923
更新日期:2009-05-21 00:00:00
abstract::Generalization is a cognitive ability that allows similar stimuli along a given dimension to be treated as equivalents. Insects exhibit high levels of visual generalization. Honeybees trained to recognize complex visual stimuli on the basis of a single feature generalize their choice to novel stimuli sharing that comm...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature02594
更新日期:2004-06-17 00:00:00
abstract::Nuclear-architecture defects have been shown to correlate with the manifestation of a number of human diseases as well as ageing. It is therefore plausible that diseases whose manifestations correlate with ageing might be connected to the appearance of nuclear aberrations over time. We decided to evaluate nuclear orga...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature11557
更新日期:2012-11-22 00:00:00
abstract::The initiation of plate tectonics on Earth is a critical event in our planet's history. The time lag between the first proto-subduction (about 4 billion years ago) and global tectonics (approximately 3 billion years ago) suggests that plates and plate boundaries became widespread over a period of 1 billion years. The ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature13072
更新日期:2014-04-24 00:00:00
abstract::More than twenty types of retinal ganglion cells conduct visual information from the eye to the rest of the brain. Each retinal ganglion cell type tessellates the retina in a regular mosaic, so that every point in visual space is processed for visual primitives such as contrast and motion. This information flows to tw...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature14103
更新日期:2015-03-12 00:00:00
abstract::Extremely intense and ultrafast X-ray pulses from free-electron lasers offer unique opportunities to study fundamental aspects of complex transient phenomena in materials. Ultrafast time-resolved methods usually require highly synchronized pulses to initiate a transition and then probe it after a precisely defined tim...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature06049
更新日期:2007-08-09 00:00:00
abstract::The signature of Dansgaard-Oeschger events--millennial-scale abrupt climate oscillations during the last glacial period--is well established in ice cores and marine records. But the effects of such events in continental settings are not as clear, and their absolute chronology is uncertain beyond the limit of (14)C dat...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature01391
更新日期:2003-02-20 00:00:00
abstract::Systems governed by time reversible equations of motion often give rise to irreversible behaviour. The transition from reversible to irreversible behaviour is fundamental to statistical physics, but has not been observed experimentally in many-body systems. The flow of a newtonian fluid at low Reynolds number can be r...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature04380
更新日期:2005-12-15 00:00:00
abstract::HIV-1 immunotherapy with a combination of first generation monoclonal antibodies was largely ineffective in pre-clinical and clinical settings and was therefore abandoned. However, recently developed single-cell-based antibody cloning methods have uncovered a new generation of far more potent broadly neutralizing anti...
journal_title:Nature
pub_type: 杂志文章,多中心研究
doi:10.1038/nature14411
更新日期:2015-06-25 00:00:00
abstract::Regulation of cell proliferation is necessary for immune responses, tissue repair, and upkeep of organ function to maintain human health. When proliferating cells complete mitosis, a fraction of newly born daughter cells immediately enter the next cell cycle, while the remaining cells in the same population exit to a ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature23880
更新日期:2017-09-21 00:00:00
abstract::Breast cancer patients with the same stage of disease can have markedly different treatment responses and overall outcome. The strongest predictors for metastases (for example, lymph node status and histological grade) fail to classify accurately breast tumours according to their clinical behaviour. Chemotherapy or ho...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/415530a
更新日期:2002-01-31 00:00:00
abstract::Established infections with the human and simian immunodeficiency viruses (HIV and SIV, respectively) are thought to be permanent with even the most effective immune responses and antiretroviral therapies only able to control, but not clear, these infections. Whether the residual virus that maintains these infections ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12519
更新日期:2013-10-03 00:00:00
abstract::Templates are widely used to arrange molecular components so they can be covalently linked into complex molecules that are not readily accessible by classical synthetic methods. Nature uses sophisticated templates such as the ribosome, whereas chemists use simple ions or small molecules. But as we tackle the synthesis...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature09683
更新日期:2011-01-06 00:00:00
abstract::Recent studies have suggested that bone marrow cells possess a broad differentiation potential, being able to form new liver cells, cardiomyocytes and neurons. Several groups have attributed this apparent plasticity to 'transdifferentiation'. Others, however, have suggested that cell fusion could explain these results...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature02069
更新日期:2003-10-30 00:00:00