Figure 2From: Real-time drilling mud gas monitoring for qualitative evaluation of hydrocarbon gas composition during deep sea drilling in the Nankai Trough Kumano BasinResults of onshore gas analyses and comparison with shipboard data. Hydrocarbon gas components in drilling mud gas samples analyzed onshore with a gas chromatograph (GC shorebased; black triangles) and quadruple mass spectrometer (QMS; red dots) compared to shipboard GC-NGA real-time data (GC shipboard, blue squares; [23]). A: C1 = methane, B: C2 = ethane, C: C3 = propane, D: (C1/(C2 + C3)) = Bernard parameter). E: Lithological column modified from [23]. “Underreamer depth” denotes the position of borehole widening and potential additional gas release caused by the underreamer. Borehole widening took place around 40 m above the borehole depth. See Methods section.Back to article page