Seafloor Geology of the Basement Serpentinite Body in the Ohmachi Seamount (Izu-Bonin Arc) as Exhumed Parts of a Subduction Zone Within the Philippine Sea - Accretionary Prisms and Convergent Margin Tectonics in the Northwest Pacific Basin - page 124

Fig. 12 Photograph of in-situ measurement using the clinometer plate at a sea-floor outcrop
(6K#1064 Loc. 5: 3,277 mbsl)

a

ψ
φ

s

b

α

d

T-axis

tanψ = s / b
sin α = b sin ψ / d
φ = ψ − α

Camera

N

b

Heading &
pan angles

τ

Pitch &
tilt angles

Line of sight

T-axis

φ

E

Pole to
the surface

Fig. 13 Theory for the measurement of surface structures by the clinometer plate. ( a ) Measure-
ment of the bar angle to the line of sight. ( b ) Stereo net projection ( upper hemisphere ) for the
relation between graphic analysis and the correspondent surface orientation