From September to October 2008, there were three lectures had been successfully conducted in the "Integrated and Continually lecture" (ICL) activity. Below is the highlight of ICL:
1. INTRODUCTION TO SEISMIC SEQUENCE STRATIGRAPHY
Date: September 6, 2008
Before we entered to Seismic Sequence Stratigraphy, Mr. Scott gave a little review about reflection seismology. We could use Reflection seismogram as a tool in three scales, like Regional, Sub-Regional, and Local. From Regional we could use it to interpret all of region (mega), Sub-Regional for individual basin (like Basin Geometry), and Local to interpret structure.
Seismic Sequence Stratigraphy reconstructs Paleogeography and Geology History. From there, we could know about Petroleum System, the geologic risk to find hydrocarbon (likes source rock, reservoir, seal rock, burial/term, trapping, and critical moment). The important thing we must know that seismic reflection couldn't always become as stratigraphic time line, for example, in carbonate build up in clastic compacted. Sometimes we could see that the carbonate would make the layers like clastic layers.
Beside that, we also learned about "seismic relation" and "seismic shapes and pattern rounded". Seismic relation was like onlap, downlap, toplap, and erosional truncation. We used it to know and to paint the sequence (usually we use red or yellow pencil to paint it).
One of participant of lecture was presenting about her seismic section.
2. SEISMIC SEQUENCE STRATIGRAPHY: PRINCIPLE OF SYSTEM TRACK ANALYSIS
Date: September 20, 2008
In this lecture, Mr. Scott introduced how to analyze the system track in order to interpret the sequence stratigraphy in the seismic data. Firstly, Mr. Scott gave some introduction about sequence stratigraphy. They were about sequences, parasequences, maximum flooding surfaces, sequence surfaces in seismic record data and the relationship with the change of sea level.
Mr. Scott also told which part onlap, downlap, and toplap in seismic record data. These variables were important to analyze the system track of the stratigraphy sequences in the seismic record data. The system track was built in parasequence of the stratigraphy units. And the sequences were composed by the system track itself. The sequence stratigraphy gave predictable succession of stratigraphy units which were related to reservoir, seal, and source rock of the hydrocarbon. The application to the seismic record data would be discussed more detail on the next lecture with the seismic record data that he gave in this lecture. Mr. Scott also gave us a task to interpret where the downlap, toplap, onlap are in the seismic section as our homework during Lebaran Day.
3. PRINCIPLE OF SEISMIC SEQUENCE STRATIGRAPHY-PART II
Date: October 18, 2008
After holiday "Idul Fitri", Mr. Stephen Scott continued our lecture by explaining about Principle of Seismic Sequence Stratigraphy. We started the lecture from analysis the Systems Tracts, and also we were showed about Exxon Method of Systems Tracts. The systems tracts were like low stand systems tract, high stand systems tract, transgressive system tract, and the other. After that, our lecture did more practice with seismic.
From seismic, we learned again about Geometry of sequence and stratigraphy relation. We practice it from three seismic data which Mr. Scott gave to us. After that, we tried to interpret the seismic section by our self, and Mr. Scott walked away to look our work. He said if we want to interpret the seismic we should do it firstly from the bottom line.
From our seismic section, Mr. Scott explained about one of sequence pattern, namely progradation. In pattern of progradation, we could get an imagination that area has a rainy season. So, the depositional would be in river. That's a little interpretation about our seismic line.
After we practiced the seismic, he explained again the petroleum system elements. But, he just explained it a little, and he promised to us that he would explain more about that on the next lecture.
American Association of Petroleum Geologist
University of Padjadjaran Student Chapter
Jatinangor, September - October 2008