Datasets of in situ stress and fracture information of four deep scientific boreholes

The data sets contain four MS Excel files with the in situ stress and fracture information from four deep scientific boreholes (Cajon Pass, Long Valley, Nevada Test Site (NTS), and German Continental Deep Drilling Program (KTB)). The raw data sets were originally provided by Prof. Mark Zoback at Stanford University, which are listed here to support 'Determination of the Crustal Friction and State of Stress in Deep Boreholes using Hydrologic Indicators' by S Zhang, X Ma, and M Zoback.

In each Excel file, gradients of the three principal stresses (S_V, S_H, S_h) and pore pressure are provided (unit: MPa / m), where is S_V the (vertical) overburden stress, S_H is the maximum horizontal stress, and S_h is the minimum horizontal stress. The orientation (theta, measured from North) of S_H is also given so that the in situ stress tensor is available for each borehole (interval).

Fractures identified by acoustic televiewer (ATV) logs are listed with their depth, dip direction (from North), dip (from horizontal plane), and hydraulic conductivity. Based on the stress gradients, the shear and normal stresses of each fracture are also calculated and presented in each file. In particular, the hydraulic conductivity of each fracture is indexed by '0' (non-conductive/impermeable) or '1' (conductive/permeable), which was previously determined by temperature logs (Barton et al., 1995, Geology; Ito and Zoback, 2000, GRL).

Citation:

 "Zhang, S., Ma, X., & Zoback, M. (2022). Datasets of in situ stress and fracture information of four deep scientific boreholes [Dataset]. Zenodo. https://doi.org/10.5281/zenodo.6585196"