Events

Bruce Ainsworth, Principal Reservoir Geoscientist, Chevron Sequence stratigraphy based on wireline logs, cores and outcrops is entering its fourth decade of mainstream usage in industry and academia. The technique has proved to be an invaluable tool for improving stratigraphic analyses in clastic shallow marine systems. In this talk we will present a simple quantitative technique to support sequence stratigraphic interpretations. The technique, utilizes two pieces of data that are readily available from every subsurface field or outcrop study; 1) parasequence thickness (T) and 2) parasequence sandstone fraction (SF). The key assumptions are that parasequence thickness can be used as a proxy for accommodation at the time of deposition, and parasequence SF can be used as a proxy for sediment supply. This means that quantitative proxies for rates of accommodation development and sediment supply can be acquired from wireline logs, cores and outcrop data. Vertical trends in parasequence thickness divided by SF (T/SF) approximate trends expected in systems tracts for changes in the ratio of rate of accommodation development to rate of sediment supply (δA/δS). The technique, termed “TSF analysis”, can also be applied at lower-order sequence and composite sequence scales. It provides a quantitative and objective methodology for determining rank and order of sequence stratigraphic surfaces and units. Absolute TSF values can be utilized to determine shoreline, stacked shoreline and shelf margin trajectories. Case studies are presented which demonstrate the robustness of the technique across a range of different data sets. Implications and potential future applications of TSF analyses will also be discussed. 

Gretchen Gillis, Geological Consultant, Aramco Americas AAPG advances the science of geology, promotes related technology, fosters the spirit of scientific research, disseminates science, inspires high standards of professional conduct, and advances the professional well-being of its members. These core purposes are as important now as they were when AAPG formed in 1917. AAPG is a mainstay of my career because of the geoscientific knowledge, networking, and education and training I have received in more 20 years of actively volunteering and from passively consuming AAPG publications earlier in my career. Recent reflection revealed my actual career drivers – fear of being laid off that has been assuaged by timely career pivots. These career pivots have provided opportunities for building skills and knowledge, and for gaining appreciation for the value of diversity and inclusion in geoscience.