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台湾上新世未岩化的利吉混杂岩是在吕宋岛弧与稳定的中国大陆边缘碰撞的初期阶段形成的。该混杂岩由剪切的鳞状泥岩基质组成,其中含有长几毫米到上千米的外来岩块和板片。这些外来岩块大都是深水砂岩和页岩以及蛇绿岩。深水砂岩和页岩解释为南中国海现已消亡部分的陆隆和深海平原沉积物,而蛇绿岩则被解释为沿着Suppe、Liou和Ern-st(1681)所讨论的中国海盆-海岭系现已消亡的转换断层的沉积产物。该混杂岩显示出1-10米的原始分层,证明大都是外来沉积岩的滑乱层并央有较薄的蛇纹岩滑乱央层和非外来的泥岩及含砾石泥岩。虽然利吉混杂岩大部分是由海相物质的外来岩块所组成,但是这种混杂岩并不是在海沟或俯冲带中形成的,因为它包含在火山岛弧的地层序列中。该混杂岩沉积上覆于晚中新世和上新世大港口层泥岩和砂岩之上。大港口层又上覆于台湾东部的吕宋火山弧西翼火山岩之上。混杂岩与大港口层之间为呈某种犬牙交错的半整合接触,混杂岩中含有大港口泥岩剥落的岩块。紧接在混杂岩接触面之下,大港口层呈现海底沉积滑动褶皱,表明该混杂岩来源于西北部。利吉和大港口含砾泥岩中所含曾受到地表侵蚀的蛇绿岩屑表明,其来源地区曾部分出露于海面以上。根据底栖有孔虫和古地理环境估算的水深表明,利吉-大港口沉积盆地就是吕宋海槽弧前盆地现已受到破坏的北延部分,它位于火山岛弧与加积带(外侧的非火山岛弧)之间。利吉混杂岩被解释为,在大陆碰撞初期阶段弧前盆地塌陷期间吕宋海槽西翼沉积的大港口层断层崖的重力滑动相。混杂岩的来源是西面扩展着的加积带。在台湾以南100公里处岛弧与大陆的碰撞目前刚刚开始,现在该处的测深海结果与晚上新世利吉-大港口沉积的推测深度很相似。与利吉混杂岩相似的混杂岩预计可在地史上的岛弧-大陆碰撞过程中广泛形成,而且不应与海沟-俯冲带的混杂岩相混淆。
The unproduced Lithi-Micite in Taiwan was formed during the initial stage of the collision between the Luzon arc and the stable continental margin of China. This melange consists of a sheared, scaly mudstone matrix containing exotic rocks and plates that range from a few millimeters up to kilometers. Most of these exotic rocks are deep-water sand and shale and ophiolite. Deep-water sandstones and shales are interpreted as Luonian and deep-sea plains deposits that are now extinct in the South China Sea, while ophiolites are interpreted along the Chinese basin-Ridge, as discussed by Suppe, Liou and Ernst (1681) The sedimentary product of the now extinct transition fault. The melange shows a 1 to 10 meter original strata that turns out to be mostly a slippery layer of exotic sedimentary rocks and has thinner serpentine slip-core and non-exotic mudstones and pebble-bearing mudstones. Although most of the Liji melange consists of marine blocks of marine material, the melange is not formed in the trench or subduction zone because it is contained in the sequence of volcanic island arc stratigraphy. The mélanges overlie the mudstones and sandstones of the late Miocene and Pliocene seams. The large port layer overlays the volcanic rocks on the west wing of the Luzon volcanic arc in eastern Taiwan. Between the melange and the port layer is a kind of intertwined semi-integrated contact, melange contains large port shale rock fragments. Immediately below the melange contact, the large seaport shows submarine sedimentary sliding folds, indicating that the mélanges originate in the northwest. The ophiolite fragments that have been subjected to surface erosion contained in the limestone and large harbor gravelly muds indicate that some of their source area had been exposed above the sea surface. The water depths estimated from the benthic foraminifera and palaeogeomorphology indicate that the Liji-Dagang Sedimentary Basin is the northern extension of the Luzon Trough pre-arboretum that has been damaged by volcanic island arcs and accretionary zones Non-volcanic island arc) between. The Liji melange was interpreted as the gravitational slip phase of the large harbor fault that deposited at the west wing of the Luzon Trough during the collapse of the Precamboidal Basin during the initial continental collision. The source of melanges is the accretionary accretion zone. The collision between the island arc and the mainland at 100 kilometers south of Taiwan is just beginning. Now the sounding sea depth at this area is very similar to the speculation depth of the late Pleistocene Litigy-Great Harbor deposition. Similar to the Liji melange, melanges are expected to form extensively during the island arc-continental collision in the history of the earth and should not be confused with melange-subduction melanges.