The hydrogen bomb and the uranium bomb are based, respectively on

The hydrogen bomb and the uranium bomb are distinguished by their primary nuclear processes. A uranium bomb, often referred to as an atomic bomb, relies on nuclear fission, where the nuclei of heavy atoms like uranium-235 are split to release energy [3]. In contrast, a hydrogen bomb is a thermonuclear weapon that utilizes nuclear fusion, the process of combining light isotopes of hydrogen (deuterium and tritium) to form helium [2]. While modern hydrogen bombs use a fission trigger to generate the immense heat required for fusion, the defining characteristic of the 'H-bomb' is the fusion reaction [1]. Therefore, the hydrogen bomb is based on fusion and the uranium bomb is based on fission. Geothermal processes are unrelated to these weapons, as they refer to heat generated within the Earth's crust [3].

Sources

1. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 5: Environmental Pollution > Atomic explosion (Nuclear fatlout): > p. 83
2. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 4: Earths Interior > Radioactive Decay > p. 58
3. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 1: The Universe, The Big Bang Theory, Galaxies & Stellar Evolution > Protostar > p. 9