Nondestructive laboratory methods
Equipment: laboratory kappa-bridge KLY-4 (AGICO s.r.o., Czech Republic)
The kappa-bridge is used to measure low-frequency magnetic susceptibility. Magnetic susceptibility (MS) is a dimensionless physical property that expresses the ability of materials to magnetize in an external magnetic field. MS can be used as a non-destructive method for identification of content of ferro- and antiferromagnetic (magnetite, hematite, maghemite), paramagnetic (clay minerals, mica) and diamagnetic minerals (quartz, calcite)
The method is suitable for non-destructive analysis of small artifacts (up to approx. 3 x 3 x 4 cm)
It is widely used in high-resolution stratigraphy of cores sampled with regular interval (for example 1 cm). Data can be used as proxy of:
content of Fe-oxo/hydroxides – (conected with pedogenesis/chemical weathering of loess and paleosoils)
content of paramagnetic phylosilicates (clays, micas) in mixture with diamagnetic quartz (common clastic sediments) – proxy of grain size variation in siliciclastics
well-known petrophysical(objective) method of separation of stratigraphic record into particular segments
Diffuse reflectance spectrometry
Equipment: portable spectral photometer SP-62 with spherical geometry (X-Rite Inc., USA).
Visible light diffuse reflectance spectrometry (Vis DRS) is widely used method for identification of chromophores (hematite, goethite, glauconite, cherts, organic matter, etc.) in solid materials. The main output of this method is reflectance curve of(0-200%) in visible part of spectrum (400-700 nm) and quantitative expression of rock colour using coulour parameters (brightness, redness index, international colour standards CIE L*a*b*, RGB, etc.). The main usage is similar to magnetic susceptibility:
for nondestructive analysis of small artifacts (ca. 1x1x1 cm)
The DRS is widely used in high-resolution stratigraphy of cores sampled with regular interval (for example 1 cm). Data (reflectance curves) can be used for:
identification of horizons with enriched content of Fe-oxo/hydroxides(hematite, magnetite, goethite), organic matter, calcite
proxy of grain size variations in clastic sediments
The DRS is well-known petrophysical(objective) method of separation of stratigraphic record into particular segments)
Laboratory gamma-ray spectrometry
Equipment: RT-50 (Georadis s.r.o., Czech Republic)
Gamma-ray spectrometry (GRS) focuses on very short wave-length part of EM spectrum (gamma-rays) emitted by natural radionuclides in solid materials. The main output are concentrations of K (%), Uranium (ppm) and Thorium (ppm), mass activity of 137Cs (Bq/kg) and assesment of whole-rock radioactivity (nGy.kg-1). In sedimentary record, these values can reflect content of K-feldspars, micas, zircon, monazite, xenotime and other heavy minerals, content of clay minerals, phosphates, organic matter, antropogenic Cs (from nuclear explosions or nuclear power plant accidents). The main usage of GRS is:
nondestructive analysis of artifacts (up to 5 x 8 x 8 cm)
The GRS is widely used in high-resolution stratigraphy of cores sampled with regular interval (for example 5 cm). Data (GRS curves) can be used for:
identification of horizons with higher content of organic matter and phosphates,
Cs dating (since 2. half of 20. Century)
proxy of mineral composition variations of rocks
Energy dispersive X-ray fluorescence spectrometry
Equipment: DELTA (Innov-X, Inc., USA)
Energy dispersive X-ray fluorescence spectrometry (EDXRF spectrometry) is used for quick and precise elemental analysis of solid materials. The main output are concentrations of elements (from Mg to U) in ppm. Ideal method for nondestructive or destructive (more precise) geochemical analysis of whole-rock samples. It is usually used for:
nondestructive chemical analysis of artifacts (ca. 2 x 2 x 1 cm)
The EDXRF spectrometry is widely used in high-resolution stratigraphy of cores sampled with regular interval (for example 5 cm). Data (GRS curves) can be used for:
identification of horizons with higher content of phosphates, antropogenic heavy metals, etc.
proxy of grain size variations
All optical methods are offered including photo/video documentation at CCD chips.
Optical polarizing microscopy
Microscopes: Olympus BX-50p, Olympus BX-41
Identification of minerals, rocks, slag, building materials, artifacts.
Identification and photodocumentaton of minerals, rocks, artifacts and microfossils. NNODESTRUCTIVE METHOD.
Microscope Leica DM 2500 P with cathodoluminescence system CL8200 MK5-1 (CITL, Great Britain)
Identification of minerals and solid material based on cathodoluminescence colours, identification of genesis and typology of minerals – calcite, zircon, quartz, feldspars, etc.
Microscope: Olympus BX41 with adapter for fluorescence microscopy Olympus BX-RFA and set of filters with excitation range 330-385 nm, 460-490 nm and 510-550 nm
It is used for identification of organic matter (hydrocarbons) in solid materials.
Microscopy with thermometric table for study of fluid inclusions
Microscope: Olympus BX51 with microthermometric chamber THMSG 600 an digital camera PixeLINK PL A 662
Study of fluid inclusions in minerals and solid materials, interpretation of genesis of minerals and solid materials, improved provenance study.
Electron microskope: JEOL (Japan) with WDX analyzators
Electron microscopy with WDX chemical analysis (microprobe) is used for very precise and objective identification of minerals nad solid materials in thin sections and chemical analysis of microscopic objects.
Shallow geophysical survey
Our geophysical methods are used for visualisation of shallow subsurface geological situation in vertical (2D) cross-sections, in map or in 3D on the basis of measurement of physical parameters of soils and rocks. Our technique is ideal for field documentation of archeological sites / waste storage conditions / stratigraphy.
Ground penetrating radar
Equipment: SIR 3000 (GSSI, USA) with antennas 200 and 400 MHz
The method is base on measurement of return time interval of EM wave reflected from subsurface interface. It is used for visualisation of boundary between rocks with different permitivity and electrical conductivity. The result is visualized in 2D section or 3D block. Used antennas reach to the depth of ca. 10 m.
Dipol electromagnetic profiling (DEMP)
Equipment: CMD (GF Instruments s.r.o., Czech Republic) with probe CMD-4 (depth range 3-6 m)
The DEMP method is used for mapping of electrical conductivity of rocks and soils. The result is map of conductivity anomalies, which can be interpreted in terms of rock composition (grain size of sediment, buried objects, etc.)
Multicable resistivity profiling
Equipment: ARES (GF Instruments, s.r.o., Czech Republic) with 8 sections of multicable with 64 electrodes
This method is used for field measurement of electrical resitivity of rocks in 2D / 3D sections (maximal depth range ca. 60 m). In sections, we can interpret rock bodies, geological structures, buried objects, etc.
Reflexion and refraction seismics
Equipment: 24-channel Terraloc Mk8 (ABEM, Sweden) with 2 cables (24 geophones)
These methods are used for field measurement of seismic interfaces in 2D sections (depth range is 5-50 m). In sections, we can interpret rock bodies, geological structures, buried objects, etc.
Portable (field) gamma-ray spectrometry (GRS)
Equipment: portable gamma-ray spectrometer GRM 260/B (GF Instruments, s.r.o., Czech Republic)
This method is used for quick assesment of the same parameters as in case of laboratory gamma-ray spectrometry (but in section or in map). The result is curve which can be interpreted in terms of stratigraphy of section or map of GRS anomalies.
Field and Laboratory works
Field geological and geodetic survey
Geological mapping, geological compass measurements, accurate localization using Ashtech ProMark500 geodetic GPS with MobileMapper 10
Shallow drilling and sampling
Drilling on land using pneumatic drilling rig for incoherent soils and rocks (Ø6 cm, up to 4 m) or soil core samplers (Ø2.5 cm, up to 5 m)
Underwater drilling and sampling (Ø 4 cm, max. water depth 5 m)
Piston cores from water surface, EWITEC system with floating platform (Ø8 cm, max. water depth 40 m)
Crushing and grinding of samples
Crushing and grinding of compacted rocks up to analytical fineness using planetary mill
Sieving for grain size analysis
Dry and wet grain size sieving analyses using FRITSCH vibration sieving machine SPARTAN 3 (full range 4 mm – 0.032 mm; standard Wenworth grain classification)
Grain size analysis using laser granulometry
Wet full range (0.008 – 2 mm) grain size analysis using laser granulometer FRITSCH Analysette 22 MicroTec plus.
Methods of separation
Separation of heavy minerals using non-toxic heavy liquids
SAMPLE PREPARATION thin section (covered) 500,- CZK/sample (only limited series)* thin section (polished) 700,- CZK/sample (only limited series)* nábrus/zalévaný preparát Ø 25 mm 400,- CZK/sample Crushing/grinding 40,- CZK/sample Sieving (dry) 80,- CZK/sample Sieving (wet) 160,- CZK/sample INSTRUMENTAL METHODS Laser Granulometry (0.08-2000 μm) 60,- CZK/sample EDXRF analysis, powdered sample 100,- CZK/sample WDX analysis, rutine, incl. preparation of tablet from powdered sample 400,- CZK/sample Assessment of mass-specific magnetic susceptibility by laboratory kappa-bridge 16,- CZK/sample Assessment of spectral reflectance (colorimetry), powdered sample 10,- CZK/sample Laboratory gamma-ray spectrometry (concetrations of K, U, Th) 160,- CZK/sample Analysis of mass activity of 137Cs by laboratory gamma-ray spectrometer (well detector) + K, U, Th 200,- CZK/sample Electron microprobe (EDX/SEM) 800,- CZK/sample SHALLOW GEOPHYSICAL SURVEY dipole electromagnetic profiling (DEMP) 500,- CZK/hour** Ground-penetrating radar (GPR),easily accessible terrain 800,- CZK/hour** Ground-penetrating radar (GPR),on water, poorly accessible terrain 1100,- CZK/hour** Electrical Resistivity Tomography (ERT) 1000,- CZK/hour** Refraction Seismics; source: hammer 1100,- CZK/hour** Reflection Seismics; source: accelerated weight-drop 1500,- CZK/hour** Hourly rate of the geophysicist´s work (field + data processing) 400,- CZK/hour Hourly rates for work helper (field) 150,- CZK/hour Transport by car 6,- CZK/Km
*The price of thin-sections and WDX analyzes of problematic materials (loose, porous,…) is based on agreement
**The price does not include the rate for the work of geophysicist and helper