As per my best understanding: railways currently active on some level in Jordan, are on the unusual 1050mm gauge -- that of the one-time Hedjaz Railway system, whose active mileage has been overall lessening over the past 100-odd years. They comprise a (relatively new) route from phosphate mines near Ma'an, well south of Amman, to a port on the Gulf of Aqaba -- for phosphate traffic only, all-diesel-worked; and the main-line route north from Amman, to the Syrian border at Dera'a (running thence on the same 1050mm gauge, to Damascus in Syria) -- has long had fairly low-level passenger and freight services, diesel-operated, and inter-working with the lines in Syria north of Dera'a. I don't know what may now be happening on these sections in Syria, what with the current situation in that country; I presume that at least a token service still runs on the Jordanian end of the line.
The Jordanian authorities have quite ambitious plans for railway replacement / new construction in the country, including links into neighbouring countries -- little or nothing seems actually to be happening, re these intentions. Any such developments would be on standard 1435mm gauge.
Although all regular rail workings in Jordan are diesel; a number of steam locos are preserved in working order in the country, and are used on occasion, on specials chartered by tour groups.
