Methodology for performing field geochemical works

Geochemical works using the passive adsorption technique are carried out along profiles or along a uniform network.

The scale of research corresponds to the zonal-regional stage of research, and also depends on the shape and size of the expected objects

At the planned points, the installation of sorbers (Geochemical samples) is carried out into the near-surface layer of soil to a depth of 30 – 40 cm. Then each sorber is saturated with hydrocarbon vapors for 17 days. Then it is placed in a sterile container, marked and sent for analysis to the laboratory.

Geochemistry by passive adsorption.

Processing and interpretation of geochemical data

Determination of the content of 81 hydrocarbon compounds.

Sample analysis data is processed using statistical methods:

  • Principal component analysis (PCA),
  • Hierarchical Cluster Analysis (IKA),
  • Discriminant Analysis (DA).

A geochemical model is built for each reference well.

Probability maps of HC distribution over the work area are constructed according to the type of each reference well.

Well geochemical model

Probability distribution of hydrocarbons by type of reference wells

Geochemical Criteria for Hydrocarbon Prediction

HC forecasting by the GC method

Map of abnormal concentrations of geochemical indicator elements