Model for Fine-Scale Movements Associated with Climate and Sea Level Changes along Louisiana Shelfbreak Growth Faults
Model for Fine-Scale Movements Associated with Climate and Sea Level Changes along Louisiana Shelfbreak Growth Faults
复制标题
路易斯安那州陆架生长断层沿线与气候和海平面变化相关的细尺度运动模型
DOI：
--
复制
发表时间：
1986
期刊：
影响因子：
--
通讯作者：
A. Lowrie
中科院分区：
文献类型：
--
作者：
A. Lowrie
摘要：沿着墨西哥湾北部，上里奥-更新世冰川循环的冰消期使可用于沉积物输送到大陆边缘的水域增加了 10 倍。随着盛冰期海平面降低，沉积脉冲沿着陆架折断区和斜坡沉积。高能量沉积会导致地基不稳定。然后，生长断层沿着货架断裂处起源。由于下面的未固结和半固结沉积物、半塑性盐和海相粘土的快速沉积导致岩石静压增加，从而促进流动，从而加速压实、流体运移、生长断层运动和盐构造。整个显生宙记录了数十年和数百年的沉积周期。行星轨道运动控制着传入的太阳辐射量和 20,000 年、40,000 年和 100,000 年的持续时间，是通过气候/海平面波动造成这些沉积循环的明显原因。当海平面较低时，沉积物沉积在陆架断线附近或之外。增加的岩石静压促进了断层的运动、下沉块体的沉积、沉积物的加速压实以及流体的排出和运移。当海平面较高时，沉积物沿着上、中陆架沉积。故障活动应该很少或没有。因此，那些记录了最大量的下沉块增长的地质事件也可能是被海平面大幅下降爆发所打断的时期。路易斯安那州陆上碳氢化合物产量通常来自沿下沉区块的最大增长部分。
ABSTRACT Along the northern Gulf of Mexico, the deglaciation phase of a Plio-Pleistocene glacial cycle produced up to a 10-fold increase in waters available for sediment transportation to continental margins. With lowered sea levels during glacial maxima, sedimentary pulses are deposited along the shelfbreak and on the slope. High energy deposition promotes foundation instability. Growth faults then originate along the shelfbreak. Increased lithostatic pressure due to rapid deposition on underlying un- and semi-consolidated sediments, semi-plastic salt and marine clays promote flowage that accelerates compaction, fluid migration, growth fault movements, and salt tectonics. Sedimentary depositional cyclicity of deca- and centenary-millennia are recorded throughout the Phanerozoic. Planetary orbital motions, controlling the amount of incoming solar radiation and of 20,000, 40,000, and 100,000 year duration, are the apparent cause of these depositional cycles via climate/ sea-level fluctuations. When sea level is low, sediments are deposited about or beyond the shelfbreak. Increased lithostatic pressure promotes movement on the fault, deposition on the down-thrown block, accelerated compaction of sediments and fluid expulsion and migration. When sea level is high, sediment deposition is along the upper and middle shelf. Fault activity should be minimal or none. Thus, those geologic episodes which record greatest amount of down-thrown block growth may also be periods punctuated by bursts of large sea level lowerings. Onshore Louisiana hydrocarbon production is usually greatest from those portions of maximum growth along down-thrown blocks.