SPATIAL THINKING AND SEQUENCE STRATIGRAPHY: WHAT ROLE DOES SPATIAL THINKING PLAY IN GEOLOGIC INTERPRETATIONS?

Skills for interpreting sequence stratigraphy and 3-D and 4-D spatial skills are thought of as important for the petroleum industry. However, little is known about the relationship between the two. This study fills part of this gap by testing the hypothesis that well developed spatial skills are a predictor of success in sequence stratigraphic interpretation. Students in the study (n=78) were enrolled in undergraduate or graduate courses teaching sequence stratigraphic concepts at one of three large U.S. universities. Students completed a survey, including a sequence stratigraphic task and two cognitive tests (hidden figures test and surface development test). The sequence stratigraphic task included a sequence stratigraphic cross-section and a Wheeler diagram. The hidden figures test evaluates disembedding or isolating an image within a busy background. The surface development test assesses mental folding/unfolding abilities. An expert rubric was created for scoring the task, and students were given an individual score for each diagram type and a combined score for the full task. Both spatial tests were scored according to the test instructions. A regression was performed to determine the amount of variance in students’ interpretation scores each spatial skill accommodated. Findings show that both disembedding and mental folding/unfolding are predictive of student success on the full task (F(1,76)=5.36, p=0.023* R²= 0.066; F(1,76)= 24.46, p=0.000***, R²=0.244 respectively) and the sequence stratigraphic diagram alone (F(1,76)=7.55 p=0.007**, R²= 0.09; F(1,76)=12.44 p=0.001** R²= 0.141; respectively). The results of the Wheeler diagram regression showed that disembedding was not a significant predictor (F(1,76)=2.575, p=0.083, R²= 0.039, ρ=0.083), while mental folding/unfolding was (F(1,76)=20.25, p=0.000***, R²= 0.210, p=0.000***). This lack of significance in disembedding may suggest that students with low disembedding skills will find Wheeler diagrams a helpful tool for interpreting sequence stratigraphy. These results show that mental folding/unfolding is particularly important to student success in sequence stratigraphic interpretation. Future studies should characterize how students utilize these skills and how to train them within the classroom.