Which one is incomplete fracture? A: linear fracture B: comminuted fracture C: spiral fracture D: Oblique fracture

Which of the following is incomplete fracture? () A: Fissured<br/>fracture B: Transverse fracture C: Oblique fracture D: Spiral<br/>fracture

Quartz exhibits conchoidal fracture.

Bedding joints are must be<br/>___ A: strike fracture B: dip fracture C: oblique fracture D: possible anyone

Which are corrrect for choosing proppant A: for low permeability formations,the fracture mainly is requires to increases the length B: for low permeability formations,the fracture mainly is requires to increases fracture conductivity C: for medium or high permeability formations,the fracture mainly is requires to increases the length. D: for medium or high permeability formations,the fracture mainly is requires to increases fracture conductivity.

“Brittle fracture”和“Ductile Fracture ”的含义分别是

fracture ( )

Which of the following statements is true about the PKN model and the KGD model? A: PKN model is suitable for the fracture with a long fracture length greater than the fracture height. B: KGD model is suitable for the fracture whose height is far greater than its length. C: The plane assumption of PKN model is the direction of fracture width and height. D: The plane of KGD model is assumed to be joint width and seam length direction.

釉质折断是（） A: enamel infraction B: crown fracture with pulp exposure C: enamel fracture D: lateral luxation

‌釉质折断是（）‎ A: enamel infraction B: crown fracture with pulp exposure C: enamel fracture D: lateral luxation