# Source Rock Prediction Using Well Log and Seismic Data:
## 5 Prediction of Source Rock Distribution
### Seismic Method  
Since the study area is large, the number of wells is small and there are no wells in the deep basin, it is necessary, after predicting the longitudinal distribution of the source rock via logging, to predict the lateral distribution of the source rock by analyzing the seismic data. The seismic method is suitable for basins with a low degree of exploration and with few wells drilled [45]. On the basis of the tectonic stratigraphic framework and DT data from 10 single wells in the study area, we compared the TOC curve of Well R in the study area with the seismic profile, identified the seismic facies characteristics of the source rocks (Figure 10), established a unified seismic facies standard, and converted the seismic facies into sedimentary facies [46]. The results show that the following three main types of seismic facies are developed in the study area: (1) the non-poor source rocks with a TOC value less than 1 wt.% are mainly characterized by a medium-strong amplitude, medium frequency, and relatively continuous and progradational reflection structures in the seismic profile, which have mainly developed in the continental slope and gentle slope zones of the basin and constitute delta subfacies deposits; (2) the medium source rocks with a TOC between 1 and 2 wt.% are mainly characterized by a medium-weak amplitude, medium-low frequency, and continuous and subparallel reflection structures, which have mainly developed in the continental slope of the study area and the transition area between the uplift and the deep basin. According to their location, they conform to the characteristics of dark mudstone deposition in the shallow lake subfacies; (3) high-quality source rocks with a TOC greater than 2 wt.% are mainly characterized by a medium-strong amplitude, a medium-low frequency, and continuous, parallel, or subparallel reflection, belonging to the seismic facies of deep lakes to semi-deep lake subfacies deposits; they were mainly developed in the depression center of the study area [47] (Figure 11).  
In order to reflect the distribution characteristics of the predicted source rocks, some seismic lines were selected for comprehensive analysis. The A-A' profile (Figure 12, the location shown in Figure 1) is located between the eastern bulge and the southern bulge of the basin and is a southeastward profile. The seismic facies near the coastline have a medium-weak amplitude, a medium-low frequency, and a continuous and subparallel reflection, showing the sedimentary characteristics of shallow lake facies. To the south, this gradually becomes a medium-strong amplitude, a medium-low frequency, and a continuous, parallel-subparallel reflection, reflecting the semi-deep-deep lake facies. Continuing to the south, and moving gradually closer to the central uplift area, the terrain is uplifted, and the seismic facies develop a medium-weak amplitude, a medium-low frequency, and  
Figure 9: TOC calculation plane distribution of Lower-Cretaceous-Albian-stage source rocks in the Côte d’Ivoire Basin.  
a continuous and subparallel reflection. The delta facies with a medium amplitude, a medium frequency, and relatively continuous and progradational reflection characteristics appeared in the southernmost part of the section. Therefore, the distribution characteristics of sedimentary facies in the study area can be obtained, which is of great significance for the subsequent prediction of the source rock distribution.  
Figure 11: Seismic facies characteristics of Albian-stage source rocks in the Côte d’Ivoire Basin.  
Figure 10: Response characteristics of the source rock in Well R well earthquake comparison.