Direct velocity measurements undertaken using a nine-system mooring array (M1-M9) from 2004 to 2005 and two additional moorings (M7p and M8p) from 2003 to 2004 reveal the spatial and temporal properties of the deep-circulation currents southwest of the Shatsky Rise in the western North Pacific. The western branch of the deep-circulation current flowing northwestward (270-10 degrees T) is detected almost exclusively at M2 (26 degrees 15'N), northeast of the Ogasawara Plateau. It has a width less than the 190 km distance between M1 (25 degrees 42'N) and M3 (26 degrees 48'N). The mean current speed near the bottom at M2 is 3.6 +/- 1.3 cm s(-1). The eastern branch of the deep-circulation current is located at the southwestern slope of the Shatsky Rise, flowing northwestward mainly at M8 (30 degrees 48'N) on the lower part of the slope of the Shatsky Rise with a mean near-bottom speed of 5.3 +/- 1.4 cm s(-1). The eastern branch often expands to M7 (30 degrees 19'N) at the foot of the rise with a mean near-bottom speed of 2.8 +/- 0.7 cm s(-1) and to M9 (31 degrees 13'N) on the middle of the slope of the rise with a speed of 2.5 +/- 0.7 cm s(-1) (nearly 4000 m depth); it infrequently expands furthermore to M6 (29 degrees 33'N). The width of the eastern branch is 201 +/- 70 km on average, exceeding that of the western branch. Temporal variations of the volume transports of the western and eastern branches consist of dominant variations with periods of 3 months and 1 month, varying between almost zero and significant amount; the 3-month-period variations are significantly coherent to each other with a phase lag of about 1 month for the western branch. The almost zero volume transport occurs at intervals of 2-4 months. In the eastern branch, volume transport increases with not only cross-sectional average current velocity but also current width. Because the current meters were too widely spaced to enable accurate estimates of volume transport, mean volume transport is overestimated by a factor of nearly two, yielding values of 4.1 +/- 1.2 and 9.8 +/- 1.8 Sy (1 Sy=10(6) m(3) s(-1)) for the western and eastern branches, respectively. In addition, a northwestward current near the bottom at M4 (27 degrees 55'N) shows a marked variation in speed between 0 and 20 cm s(-1) with a period of 45 days. This current may be part of a clockwise eddy around a seamount located immediately east of M4. (C) 2010 Elsevier Ltd. All rights reserved.