Nanoscale constraints on porosity generation and fluid flow during serpentinization
Nanoscale constraints on porosity generation and fluid flow during serpentinization
复制标题
蛇纹石化过程中孔隙度产生和流体流动的纳米级限制
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
W. Seyfried
中科院分区：
文献类型：
--
作者：
B. Tutolo;D. Mildner;C. Gagnon;M. Saar;W. Seyfried
富含橄榄石的岩石的现场样品几乎总是蛇纹石化的——通常
直到完成，但矛盾的是，它们的内在孔隙度和渗透率却越来越低。
蛇纹石化反应是通过流体渗透、体积测量的耦合过程发生的
膨胀和反应驱动的压裂。过程中产生的孔隙和反应表面积
这个过程是流体渗透到蛇纹石化并与蛇纹石化反应的主要途径
岩石，但这些孔隙的大小和分布以及表面积尚未被描述。
在这里，我们利用中子散射技术来首次测量中子
部分蛇纹石化岩石中孔径和比表面积分布的演变。
样品是从大约获得的。 2 Ma 亚特兰蒂斯地块海洋核心复合体位于离轴处
大西洋中脊和约富含橄榄石的露头。 1.1 Ga 德卢斯综合体
北美中部大陆裂谷。我们的测量和分析表明
蛇纹石和副相具有其自身固有的孔隙率，可容纳
蛇纹石化过程中大量扩散流体流动，从而允许继续蛇纹石化
大量蛇纹石矿物填充反应产生的孔隙后。
Field samples of olivine-rich rocks are nearly always serpentinized—commonly
to completion—but, paradoxically, their intrinsic porosity and permeability are diminishingly low.
Serpentinization reactions occur through a coupled process of fluid infiltration, volumetric
expansion, and reaction-driven fracturing. Pores and reactive surface area generated during
this process are the primary pathways for fluid infiltration into and reaction with serpentinizing
rocks, but the size and distribution of these pores and surface area have not yet been described.
Here, we utilize neutron scattering techniques to present the first measurements of the
evolution of pore size and specific surface area distribution in partially serpentinized rocks.
Samples were obtained from the ca. 2 Ma Atlantis Massif oceanic core complex located off-axis
of the Mid-Atlantic Ridge and an olivine-rich outcrop of the ca. 1.1 Ga Duluth Complex of
the North American Mid-Continent Rift. Our measurements and analyses demonstrate that
serpentine and accessory phases form with their own, inherent porosity, which accommodates
the bulk of diffusive fluid flow during serpentinization and thereby permits continued serpentinization
after voluminous serpentine minerals fill reaction-generated porosity.
影响因子：
3.9
作者：
Beard, James S.;Frost, B. Ronald;Sharma, Shiv K.
通讯作者：
Sharma, Shiv K.