Petrology of serpentine sandstone as a key to tectonic development of serpentine belts
Petrology of serpentine sandstone as a key to tectonic development of serpentine belts
复制标题
蛇纹石砂岩岩石学是蛇纹岩带构造发育的关键
DOI：
10.1016/0040-1951(91)90144-h
复制
发表时间：
1991
期刊：
影响因子：
2.9
通讯作者：
H. Okada
中科院分区：
文献类型：
--
作者：
S. Arai;H. Okada
蛇纹岩带中普遍存在的蛇纹砂岩的岩石学特征，可以为消失或侵蚀的蛇纹岩块体提供一些岩石学特征的约束。碎屑Chrome尖晶石和Chrome透辉石的化学成分是橄榄岩源岩平衡温度和岩性的有用指示剂。结合相关蛇纹岩块的岩石学，这可以提供丢失的蛇纹岩和现在暴露在蛇纹岩带中的蛇纹岩之间的岩石学特征的差异（如果有的话），因此可以对蛇纹岩带本身的构造历史施加一些限制。在日本中部的狭窄蛇纹岩带峰冈带中，中新世期间出露的蛇纹岩块体经历了较低的辉石温度和较宽的岩性，而现在同一地区出露的蛇纹岩块体则经历了较低的辉石温度和较宽的岩性。这一事实可能表明，上地幔橄榄岩的垂直切片自中新世以来已被抬升和间歇性突出。峰冈带可能位于菲律宾海板块北方端四国盆地开口处的一个化石横断层的一部分上。沿着平移断层，具有各种岩石学特征的地幔橄榄岩片可能以与现今大洋断裂带相同的方式连续侵位。另一方面，在日本北方的北海道的Kamuikotan带，在Furenai的中新世蛇纹砂岩的源具有与现在伴生的猿川橄榄岩体相同的岩石学特征。猿川岩体是中新世欧亚板块与鄂霍次克（北美）板块碰撞期间隆起的蛇绿岩套的肢解部分。中中新世时，在猿川橄榄岩体内的一个小沉积盆地中产出了伏仁内蛇纹砂岩。与峰冈带相反，中新世之后，在Kamuikotan带没有发生橄榄岩体的大的垂直隆起运动。
The petrology of serpentine sandstone, which is ubiquitous in the serpentine belt, could provide some constraints on petrological characteristics for lost or eroded serpentinite masses. The chemistry of detrital chrome spinel and chrome diopside in particular is a useful indicator of the equilibrium temperature and lithology of the source peridotite. Combined with the petrology of the associated serpentinite masses this could provide the difference in the petrological characteristics, if any, between the lost serpentine and that now exposed in a serpentine belt, and consequently some constraints could be placed on the tectonic history of the serpentine belt itself.In the Mineoka belt, a narrow serpentine belt in central Japan, the serpentinite mass exposed during the Miocene has experienced a lower pyroxene temperature and wider lithology than the serpentinite masses now exposed in the same area. This fact possibly indicates that a vertical slice of the upper mantle peridotite has been uplifted and intermittently protruded since the Miocene. The Mineoka belt is probably placed on part of a fossil transcurrent fault, which had worked in the opening of the Shikoku Basin, of the northern end of the Philippine Sea plate. Along the transcurrent fault the mantle peridotite slices with various petrologic characteristics could have been continuously emplaced in the same way as in the present-day oceanic fracture zone. On the other hand, in the Kamuikotan belt of Hokkaido, northern Japan, the source of a Miocene serpentine sandstone at Furenai has the same petrologic characteristics as the now associated Sarugawa peridotite mass. The Sarugawa mass is a dismembered part of an ophiolite suite uplifted during the collision between the Eurasia plate and the Okhotsk (North America) plate in Miocene times. The Furenai serpentine sandstone was produced in a small sedimentary basin within the Sarugawa peridotite mass during the middle Miocene. Contrary to the Mineoka belt, large vertical uplift movements of the peridotite mass did not occur in the Kamuikotan zone after the Miocene.