Rapid migration of a magma source from mid- to deep-crustal levels: Insights from restitic granulite enclaves and anatectic granite

2017 ◽  
Author(s):  
Kai Zhao ◽  
Xisheng Xu ◽  
Saskia Erdmann ◽  
Lei Liu ◽  
Yan Xia
Keyword(s):  
Magma Source ◽  
Anatectic Granite

SYSTEMATIC MIDDDLE TO LATE JURASSIC CHANGES IN MAGMA SOURCE IN THE MOJAVE SEGMENT OF CALIFORNIA’S CONTINENTAL ARC

2016 ◽  
Author(s):  
Jade Star Lackey ◽  
◽  
Kyle R. McCarty ◽  
Anne A. Fulton ◽  
Juliet Ryan-Davis ◽  
...  
Keyword(s):  
Late Jurassic ◽  
Magma Source ◽  
Continental Arc

ISPY SAN CRISTOBAL'S MAGMA SOURCE: THE GALAPAGOS ISLAND EDITION

2018 ◽  
Author(s):  
Regina Pimentel ◽  
◽  
Karen Harpp ◽  
Dennis Geist ◽  
Hannah Bercovici ◽  
...  
Keyword(s):  
Magma Source ◽  
Galapagos Island

scholarly journals Geochemical Variation of Miocene Basalts within Shikoku Basin: Magma Source Compositions and Geodynamic Implications

Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Shuang-Shuang Chen ◽  
Tong Hou ◽  
Jia-Qi Liu ◽  
Zhao-Chong Zhang
Keyword(s):  
Japan Sea ◽  
Isotopic Signature ◽  
Magma Source ◽  
Isotopic Compositions ◽  
Enriched Mantle ◽  
Shikoku Basin ◽  
Depleted Mantle ◽  
Parece Vela Basin ◽  
Back Arc ◽  
Ocean Ridge

Shikoku Basin is unique as being located within a trench-ridge-trench triple junction. Here, we report mineral compositions, major, trace-element, and Sr-Nd-Pb isotopic compositions of bulk-rocks from Sites C0012 (>18.9 Ma) and 1173 (13–15 Ma) of the Shikoku Basin. Samples from Sites C0012 and 1173 are tholeiitic in composition and display relative depletion in light rare earth elements (REEs) and enrichment in heavy REEs, generally similar to normal mid-ocean ridge basalts (N-MORB). Specifically, Site C0012 samples display more pronounced positive anomalies in Rb, Ba, K, Pb and Sr, and negative anomalies in Th, U, Nb, and Ta, as well as negative Nb relative to La and Th. Site 1173 basalts have relatively uniform Sr-Nd-Pb isotopic compositions, close to the end member of depleted mantle, while Site C0012 samples show slightly enriched Sr-Nd-Pb isotopic signature, indicating a possible involvement of enriched mantle 1 (EM1) and EM2 sources, which could be attributed to the metasomatism of the fluids released from the dehydrated subduction slab, but with the little involvement of subducted slab-derived sedimentary component. Additionally, the Shikoku Basin record the formation of the back-arc basin was a mantle conversion process from an island arc to a typical MORB. The formation of the Shikoku Basin is different from that of the adjacent Japan Sea and Parece Vela Basin, mainly in terms of the metasomatized subduction-related components, the nature of mantle source, and partial melting processes.

The relationship between the height of a volcano and the depth to its magma source zone: A critical reexamination

1992 ◽  
Vol 19 (13) ◽  
pp. 1395-1398 ◽  
Author(s):  
Lionel Wilson ◽  
James W. Head ◽  
Elisabeth A. Parfitt
Keyword(s):  
Source Zone ◽  
Magma Source ◽  
The Relationship

Collision and reactivation along the South Tianshan Orogen (NW China) through late Paleozoic to Mesozoic time

2021 ◽  
Author(s):  
Yigui Han ◽  
Guochun Zhao
Keyword(s):  
Continental Collision ◽  
Orogenic Belt ◽  
Late Paleozoic ◽  
Magma Source ◽  
The South ◽  
Nw China ◽  
Magmatic Rocks ◽  
Western Tianshan ◽  
Tarim Craton ◽  
South Tianshan

<p>The South Tianshan Orogenic Belt in NW China marks the suturing site between the Tarim Craton and the Central Asian Orogenic Belt (CAOB) during late Paleozoic-Mesozoic time. Despite numerous investigations, the amalgamation history along the South Tianshan Orogen remains controversial, especially on the timing and process of the final continental collision between the Tarim Craton and the Central Tianshan (CTS)-Yili Block. We inquire into this issue on the basis of a compiled dataset across the Tarim, South Tianshan and CTS-Yili regions, comprising elemental and isotopic data of magmatic rocks and radiometric ages of regional magmatism, detrital zircons, (ultra-)high pressure metamorphism and tectonothermal events. The data support a continental collision along the South Tianshan belt in 310-300 Ma, in accord with a contemporaneous magmatic quiescence and a prominent decrease of εNd(t) and εHf(t) values of magmatic rocks in the CTS region, and a main exhumation stage of (U)HP rocks in the South Tianshan region. The collisional orogeny along the South Tianshan have most likely been influenced by a mantle plume initiated at ca. 300 Ma underneath the northern Tarim Craton, as evidenced by temporal and spatial variations of geochemical proxies tracing magma source characteristics. The new model of plume-modified collision orogeny reconciles the absence of continental-type (U)HP rocks in the orogen and the insignificant upper-plate uplift during continental collision. In the mid-Triassic (ca. 240 Ma), the Chinese western Tianshan underwent intense surface uplift and denudation, as indicated by sedimentary provenance analysis and tectonothermal events. Paleocurrent and detrital zircon age data from Triassic strata in northern Tarim suggest a provenance change from a single source of the Tarim Craton to multiple sources including the CTS-Yili Block to the north and the Western Kunlun Orogen to the south. We suggest that the mid-Triassic uplifting in Chinese western Tianshan was an intracontinental orogeny caused by far-field effects of the collision between the Tarim Craton and the Qiangtang Block. This research was financially supported by NSFC Projects (41730213, 42072264, 41902229, 41972237) and Hong Kong RGC GRF (17307918).</p>

Volcano dynamics vs tectonics on Mars: evidence from Pavonis Mons

2021 ◽  
Author(s):  
Riccardo Pozzobon ◽  
Diana Orlandi ◽  
Carolina Pagli ◽  
Francesco Mazzarini
Keyword(s):  
Structural Features ◽  
Magma Source ◽  
Magmatic Activity ◽  
Normal Faulting ◽  
Azimuthal Distribution ◽  
Structural Mapping ◽  
Volcanic Province ◽  
Magmatic Source ◽  
Rocky Planets ◽  
Topographic Distribution

<p>Volcanic activity is widespread within the inner Solar system and it can be commonly observed on rocky planets.<br>In this work, we analyse the structures of Pavonis Mons, which is one of the three large volcanoes in the Tharsis volcanic province of Mars, by performing structural mapping, azimuth, and topographic distribution of linear features on the flanks of Pavonis, such as grabens and pit chains. We tested whether their formation is to be ascribed to the internal volcano dynamics and magmatic activity or the tectonics related to the Tharsis volcanic province activity.<br>Through the length size distribution and fractal clustering analyses of the structural features, we found that large grabens are vertically confined in the upper mechanical layers of the brittle crust whereas pit chains penetrate the whole crust up to the magmatic source, indicating that they can be considered the main feeders of Pavonis Mons. We inverted the topography with dykes and faults models to test whether grabens at the surface are the expression of intrusions at depth and we suggest that thin dykes inducing normal faulting is the most likely mechanism. Furthermore, two azimuthal distribution of the grabens are identified: concentric grabens occur on the volcano summit while linear grabens at its base show NE-SW trend as the Tharsis Montes volcanoes alignment. The analyses show that faults related to large grabens are confined in a mechanical layering in the upper layers of the brittle crust, whereas deeper structures such as pit chains are most likely associated to magma injection/dykes and therefore, connected to the subcrustal magma source at a depth of ~80–100 km.<br>Therefore, based on our results, we infer that Pavonis Mons recorded active rifting at the initial stages of development with the formation of the large linear graben and faults at its base followed by a phase of volcano growth and concentric magma intrusions when volcano and magma chamber dynamics prevailed</p>

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