On expedition

Nagqu
One of the biggest (bigger than California!) yet least traveled prefecture's of Tibet is that of Nagqu (alternatively Nagchu). This is all the more illustrated by using for instance flickr. The search term Nagqu only gets 83 hits, less than 1% of the number of hits Shigatse would get (figures from 2010)! Instagram gives 28 for Nagqu, 1428 for Shigatse ...!

Anyway, that probably means that researching the depth of information on hot springs in Nagqu will not be very rewarding. And complicating:  some websites placing Yangbajing hot spring in this prefecture (Yangbajing alone counts for 10.000 or so links). So when raking through the potential links for say Nagqu, it's quite difficult to find genuine Nagqu hot springs.

But still if one seeks, one finds. Dor Ji [1] mentions Gulug boiling fountain of Nagqu county. Another link to this hot spring is an article entitled, 'Chronology of the Gulu hot spring Cesium deposit in Nagqu, Tibet and it geographical significance'[2].Dor Ji also mentions a warm spring located in Nagqu town:

'The thermal water has temperature of 40-61C. A small scale geothermal power plant was also constructed here in the 1990s.
...
In addition, the Nagqu Geothermal Power Plant installed a 1 MW binary unit in 1993 but production was terminated due to serious scaling problems'.

The article also has a map with lots of red dots showing Tibet's more than 600 estimated hot springs! [Tibettravel.org puts an estimate of 1000+!]

A website promoting tourism in Nagqu (if allowed to come) once used to mention more than 200 soaking sites alone in Nagqu!

The following picture is taken from a Chinese language website. After translation it conspires that this is the first non-natural pool in Nagqu prefecture, it may well be called Lhomar and it's located 30 km's from Nagqu city.

Ancient art and soaking
Rongma hot springs, Nyima county find themselves often on tour programmes as there are also murals worth visiting:

'The picture on the stone can also change with the change of the season and time'.

There was once an expedition (?) to 'north Tibet" which expanded our knowledge on these springs:

'There are three layers in the hot springs. We stood on a piece of flat sand land, the first layer. Nearby there is a wading pool of nearly 200 square meters, with numberless spouting spring mouths. At the right of the pool, stalactites have accumulated over thousands of years, and one or two spring mouths can often be found in the middle or beside them. Some mouths have water spouting out, and some have no water but only a sound. At the right corner of the pool there is an earth hole, and the superfluous water of the pool overflows to an underground passage by this way and runs to the small river below.
There are some small spring mouths on the second layer. It is small compared with the spring pool aforementioned. In fact, each spring mouth on the second layer is able to spout enough water to make a pool. These spring mouths are obviously older than the spring pool. The stalactites there are solid and tall, in different shapes, some like a marmot watching the moon with its babies, some like playing monkeys and some like mother giving milk to babies.
The third layer is beside the small river. Tall stalactites have formed exquisite rockwork after being sculpted by superlative craftsmanship over many years. Lucid river water sometimes runs into a cave and flows on to another. There are two spring mouths in the river water at the cave mouth. The spring water spouting out creates an excellent sight with the tall stalactites.
Between the second and the third layer, there are two slopes, frozen now. With sunlight spreading on the ice surface, the colors change. The shape of each spring mouth is different; some only have one spring mouth, overflowing intermittently; the water is lucid and bright, but the sediment at the bottom is of different colors: green, pink, light yellow and milky white.
Rongma hot springs are still in a pure natural state. Except for two stone pagodas and sutra flags beside the upper wading pool, there is no man-made mark. According to local people, nobody goes there except locals washing clothes'.

Rongma hot spring photo by Single Singer

One must note that Rongma hot spring is quite unique:

'The Rongma Hot Spring is a collection of naturally warm springs that span over hundreds of kilometers'.

Exposing skin
Also in Nyima county is the hot springs of Wenbo; the excellent aforementioned expedition of north Tibet describes:

'The altitude of the hot spring is 4,516 meters, a little lower than Rongma hot springs, but the climate is much worse. The spring mouth is halfway up the hill. There are only 100 meters from our parking place to the spring mouth, but we spent 20 minutes getting there. We actually panted three times for every step.
There is only one spring mouth, as large as a bowl, overflowing water. Local people dug out two hollows below, one large and one small surrounded by gravel. The larger one has a tall and glossy wall with a small hole for the overflow, available for three people to bathe at once; it is especially for men. The smaller one is especially for women and the wall is less than half a meter. Standing in the men's pool, one can see everything in the women's pool where not only the cold wind cannot be prevented but also privacy is nil.
I could not resist the inducement of that green pool, and began to take off three cold-resistant military overcoats. Once the skin was exposed to the cold wind, it was so cold that I felt the bones hurting, which is unimaginable for people who have never been to northern Tibet in winter. When stepping into the pool, it was so comfortable that I felt each pore was breathing.
The shining sun is just overhead, and the ultraviolet radiation shines on the skin by reflection from the water surface like a lot of small needles. I tried to hide my body under the water and hide my head in the shadow of the wall and began to relax with eyes closed. The northern wind howled outside the wall; the scene inside the wall is exuberant, stalactites covered by green lichen, and the spring water rushing into the pool, making the sound of "large and small pearls falling on a jade plate".
Gongzha told me that during the Bathing Festival every year all people living for hundreds of miles around come here to bathe. The bathing rules are very strict. For example, the first bathing duration is 10 minutes, the second 15 minutes, and the third 20 minutes, and so on until you reach the longest duration you can bear. And then, one should reduce the time by five minutes one after another until returning to the beginning.
During the Bathing Festival every year, as there are so many people, an old Tibetan doctor will arrange the time depending on individual person's situation, such as 15 minutes or half an hour, and everybody will step into the pool by turns. It is said that by bathing for a week during the Bathing Festival one will not catch a cold in a year.

Hissing
As if this was not enough, the expedition to Nagqu as described in Tibetmagazine features the hot springs of Lhaya, however it's unclear where exactly they are other than on the border between Shigatse and Nagqu:

'Lhaya Hot Spring is in the river valley beside the road. From far away we saw mist curling up in the valley and heard the "hiss" of the spurting spring spreading far into the valley.
There are two springs in the center of the river, with one discharging directly into the river, the spring water creating a circle of some one square meter like an umbrella on the river surface; the other one is what people call a 'multicolored spring'. In center of the river, stands a round stalactite some 100 cm higher than the river surface that emits different color from the sun's rays. The spring water spurts out from the middle of the stone, as high as about one meter, and is very beautiful. Many fish without any scales swim around the spring. ... The spring is in the center of the river and access is impossible, which is a pity'.

According to wikipedia the village of Dongqiao (Amdo county) is noted for it's hot spring of Jipu. But that's all what the internet will reveal on this subject.

Notes:
[1] Dor Ji (2008) Geothermal Resources and Utilization in Tibet and the Himalayas. Presented at the Workshop for Decision Makers on Direct Heating Use of Geothermal Resources in Asia, organized by UNU-GTP, TBLRREM and TBGMED, in Tianjin, China, 11-18 May, 2008.
[2] Zhao Yuanyi , Zhao Xitao , Ma Zhibang & Deng Jian [unknown] Chronology of the Gulu Hot Spring Cesium Deposit in Nagqu, Tibet and It Geological Significance. Institute of Mineral Resources, CAGS, Beijing, China