Mobilisation of deep crustal sulfide melts as a first order control on upper lithospheric metallogeny.
Mobilisation of deep crustal sulfide melts as a first order control on upper lithospheric metallogeny.
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深部地壳硫化物熔体的活化是上层岩石圈成矿的一级控制。
DOI：
10.1038/s41467-022-28275-y
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发表时间：
2022-01-31
影响因子：
16.6
通讯作者：
Gorczyk W
中科院分区：
文献类型：
--
作者：
Holwell DA;Fiorentini ML;Knott TR;McDonald I;Blanks DE;Campbell McCuaig T;Gorczyk W
岩浆弧是一种陆地环境，在那里岩石圈的循环和金属和挥发分的循环得到加强。然而，允许这些元素从地幔到外层地球圈的间歇性流动的一级机制一直难以捉摸。为了解决这一认识差距，我们重点研究了赋存于地壳最下部角闪石-橄榄石-辉石堆积体中的富金属岩浆硫化物的结构和矿物化学特征。结果表明，在因长期镁铁质岩浆作用而升温的堆积岩中，富Cu-Au硫化物以液态形式存在，而富Ni-Fe硫化物以固相形式存在。这种情况发生在约1100-1200 °C的“金色”温度带内，这是典型的弧形地壳底部，允许富铜、金的硫化物液体时不时地分馏和流动到可渗透的熔体网络中，该网络可能向上穿过岩石圈，为斑岩和浅成热液矿床提供金属。富含金属的硫化物在下地壳岩浆室中的存在和移动性可以作为金属被捕获或释放到上升岩浆中的门户，然后上升的岩浆能够形成上地壳斑岩铜金矿。
Magmatic arcs are terrestrial environments where lithospheric cycling and recycling of metals and volatiles is enhanced. However, the first-order mechanism permitting the episodic fluxing of these elements from the mantle through to the outer Earth’s spheres has been elusive. To address this knowledge gap, we focus on the textural and minero-chemical characteristics of metal-rich magmatic sulfides hosted in amphibole-olivine-pyroxene cumulates in the lowermost crust. We show that in cumulates that were subject to increasing temperature due to prolonged mafic magmatism, which only occurs episodically during the complex evolution of any magmatic arc, Cu-Au-rich sulfide can exist as liquid while Ni-Fe rich sulfide occurs as a solid phase. This scenario occurs within a ‘Goldilocks’ temperature zone at ~1100–1200 °C, typical of the base of the crust in arcs, which permits episodic fractionation and mobilisation of Cu-Au-rich sulfide liquid into permeable melt networks that may ascend through the lithosphere providing metals for porphyry and epithermal ore deposits. The presence and mobility of metal-rich sulfides in lower crustal magma chambers can act as a gateway for metals to be trapped, or released into ascending magmas that are then able to form upper crustal porphyry copper and gold deposits.
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影响因子：
4.8
作者：
Hronsky, Jon M. A.;Groves, David I.;Begg, Graham C.
通讯作者：
Begg, Graham C.
DOI：
10.2113/gsecongeo.85.2.328
发表时间：
1990-03-01
期刊：
ECONOMIC GEOLOGY AND THE BULLETIN OF THE SOCIETY OF ECONOMIC GEOLOGISTS
影响因子：
--
作者：
GARUTI, G;NALDRETT, AJ;FERRARIO, A
通讯作者：
FERRARIO, A
影响因子：
3.5
作者：
Kloetzli, Urs S.;Sinigoi, Silvano;Guenes, Zekerias
通讯作者：
Guenes, Zekerias
影响因子：
1.2
作者：
Loucks, R. R.
通讯作者：
Loucks, R. R.
影响因子：
5
作者：
Fiorentini, Marco L.;LaFlamme, Crystal;Thi-Hao Bui
通讯作者：
Thi-Hao Bui