X
- XC – Cross-connection, cross correlation
- XL – or EXL, Exploration Licence (United Kingdom), a type of onshore licence issued between the First Onshore Licensing Round (1986) and the Sixth (1992)
- Xln – Crystalline (minerals)
- XLPE -Cross-linked Polyethylene
- XMAC – Cross-Multipole Array Acoustic log
- XMAC-E – XMAC Elite (Next generation of XMAC)
- XMRI – Extended Range Micro Imager (Halliburton)
- XMT/XT/HXT – XMas Tree (Christmas Tree, the valve assembly on a production well-head)
- XO – Cross-Over
- XOM – Exxon Mobil
- XOV – Cross-Over Valve
- XPERM – Matrix Permeability in the X-Direction
- XPHLOC – Crossplot Selection for XPHI
- XPOR – Crossplot Porosity
- XPT – Formation Pressure Test log (Schlumberger)
- XYC – XY Calliper Log (Halliburton)
Read more about this topic: List Of Oil Field Acronyms