Seismic Stratigraphy and Global Changes of Sea Level: Part 5. Chronostratigraphic Significance of Seismic Reflections: Section 2. Application of Seismic Reflection Configuration to Stratigraphic Interpretation

摘要: Primary seismic reflections follow chronostratigraphic (time-stratigraphic) correlation patterns rather than time-transgressive lithostratigraphic (rock-stratigraphic) units. Physical surfaces that cause are primarily stratal and unconformities with velocity-density contrasts. Stratal major bedding thus represent ancient depositional surfaces. Unconformities of erosion or nondeposition significant gaps. Both have time significance because the Law Superposition. In terms geologic time, from approximate time-synchronous events, where commonly time-variable. However, unconformity time-significant all strata below older above unconformity. No physical surface could generate a reflection parallel top formation (lithostratigraphic unit) exists in nature. The continuity follows across boundaries, although character (amplitude, cycle breadth, waveform) will change as coefficients spacing laterally. Commonly, given transgresses rock time. Geologic correlations made paleontologic data tie seismic-reflection even latter cross facies boundaries. addition, their correlative conformities bound sequences, also zones especially Paleozoic Mesozoic. Understanding relating them to available well control is essential for stratigraphic trap exploration. There other types continuous locally present sedimentary rocks. Most these gas-water, gas-oil, oil-water fluid contacts gas hydrate zones. Reflections cut originating surfaces, if they at an angle each other. Chronostratigraphic accurate only ± 1/2 breadth owing possible changes caused by bed coefficients.