Geotechnical exploration methods like boring and sampling play a crucial role in mining by assessing subsurface conditions. Boring techniques used in mining include diamond core drilling and reverse circulation drilling to obtain core samples and bulk samples. Once drilled, samples are collected using various techniques including core sampling, grab sampling, and channel sampling. Samples are tested in laboratories to analyze mechanical properties and suitability for mining. Geotechnical engineers then interpret the data to evaluate site conditions, hazards, and design parameters to guide safe and efficient operations.

1. LESSON PLAN
Week:
Taught By: -------------
Date: _______
Subject: Introduction to Geology and Geological Investigation
Time: 120 min
Topic: Geotechnical Exploration Method (Boring & Sampling)
Objective(s):Student will know about
Rock Explorations
Rock Description Sequence
Engineering properties of Rocks (Physical and mechanical)
Skill Focused on: Introduction to Geology and Geological Investigation
Resources: Marker, Board, Multimedia
Text book: Introduction to investigate Rocks parameters & Techniques developments
Methodology:
First I’ll give brief introduction about Geology & Geological Methods
Geotechnical exploration methods, including boring and sampling, play a crucial role in mining
operations. These methods are used to assess the subsurface conditions within a mine site and provide
valuable information for mine planning, design, and safety considerations. Let's explore how boring and
sampling are conducted in the context of mining.
Boring in Mines: In mining, the primary objective of boring is to obtain geological and
geotechnical data about the rock formations within the mine area. Boring techniques used in
mining may include:
a. Diamond Core Drilling: Diamond core drilling is the most common method used in
mining exploration. It involves drilling boreholes using a rotating diamond-tipped drill
bit. This method provides high-quality, continuous core samples that are representative
of the rock formations encountered. The core samples can be analyzed for their mineral
composition, physical properties, and geotechnical characteristics.
b. Reverse Circulation (RC) Drilling: RC drilling is widely used in mining to obtain bulk
samples of mineralized material. It involves using a dual-wall drill pipe system.
Compressed air is pumped down the outer annular space, while the cuttings are drawn up
through the inner tube, preserving the sample integrity. RC drilling is particularly useful
for exploration and grade control purposes in open-pit mining operations.
Sampling in Mines: Once the borehole is drilled, various sampling techniques are used to
collect representative samples of the rock formations for laboratory testing. These techniques
may include:
a. Core Sampling: In diamond core drilling, the extracted core samples are typically used
for geological and geotechnical analysis. The core is split lengthwise, and half of it is
retained for further testing and reference. Core samples are especially valuable for
assessing the rock strength, mineral content, and potential geological hazards.
b. Grab Sampling: Grab sampling involves collecting smaller rock or mineral samples
from various locations within the mine workings. This technique is often used for

2. preliminary assessments of ore quality, grade control, and short-term decision-making.
c. Channel Sampling: Channel sampling is commonly employed in underground mines. It
involves cutting a continuous channel across a mineralized zone exposed in a drift or
tunnel wall. This method provides information about the orebody's grade, continuity, and
structure.
Laboratory Testing: The samples collected from mining operations are sent to laboratories
for testing and analysis. Geotechnical laboratory tests may include uniaxial and triaxial
compressive strength tests, rock mass classification, mineralogical analysis, and other
specialized tests specific to mining activities. These tests provide valuable data to assess the
rock's mechanical properties, stability, and suitability for mining activities.
Interpretation and/ Reporting: Geotechnical engineers and geologists interpret the data
obtained from the drilling and laboratory tests to evaluate the geotechnical conditions of the
mine site. They assess the rock mass quality, potential geotechnical hazards, stability of the
mine workings, and design parameters for underground excavations or open-pit slopes. The
findings are documented in geotechnical reports, which guide mine planning, support
decision-making, and ensure safe and efficient mining operations.
It's important to note that mining exploration and geotechnical practices can vary depending on the type
of deposit, mining method, and specific project requirements. Experienced geotechnical professionals
with expertise in mining exploration are typically involved in overseeing and conducting these activities
to ensure accurate data collection and analysis for safe and successful mining operations.
Rock Explorations In Mines
Rock exploration in mines is an essential process for understanding the geological characteristics of the
rock formations within a mining site. It involves conducting detailed studies and assessments to determine
the quality, quantity, and suitability of the mineral deposits for extraction. Here are some key aspects of
rock exploration in mines:
Geological Mapping: Geological mapping is conducted to identify and map the different
rock formations present in the mine area. This includes documenting the lithology (rock
types), structure (folds, faults, fractures), and other geological features. Geological maps help
in identifying potential mineralized zones and planning mining activities.
Remote Sensing: Remote sensing techniques, such as aerial photography, satellite imagery,
and LiDAR, can provide valuable data for understanding the surface geology and identifying
potential areas of mineralization. These methods help in delineating rock units, structural
trends, and alteration zones over large areas.
Geophysical Surveys: Geophysical methods are used to investigate the subsurface geology
and detect mineral deposits. Techniques like magnetic surveys, gravity surveys, induced
polarization (IP), and electrical resistivity imaging can provide information about the rock
properties, structural features, and potential mineralization targets.
Drilling and Sampling: Drilling is a primary method for collecting rock samples from
various depths within the mine. Diamond core drilling is commonly used in mining
exploration to obtain high-quality samples. The core samples are recovered and analyzed to
determine the mineral content, grade, texture, and other relevant parameters. The samples are
also used for geotechnical testing to assess rock strength and stability.

3. Assay and Laboratory Analysis: Rock samples obtained from drilling are sent to the
laboratory for assay and analysis. Assay tests determine the concentration and distribution of
valuable minerals in the samples. Laboratory analysis may include mineral identification,
grain size analysis, chemical analysis, and other tests to determine the rock's physical and
chemical properties.
Data Integration and Interpretation: The data collected from geological mapping, remote
sensing, geophysical surveys, drilling, and laboratory analysis are integrated and interpreted
to generate geological models and resource estimates. This includes delineating mineralized
zones, estimating ore reserves, and evaluating the economic viability of mining operations.
Mine Planning and Development: The findings from rock exploration are crucial for mine
planning and development. The geological models and resource estimates are used to design
mine layouts, determine mining methods, and optimize extraction strategies. Geotechnical
data obtained during exploration helps in designing stable slopes, tunnels, and underground
excavations.
Environmental Considerations: Rock exploration in mines also includes assessing the
environmental impact and mitigating potential risks. Environmental studies evaluate the
effects of mining activities on water resources, air quality, biodiversity, and surrounding
ecosystems. This information is used to develop environmental management plans and
ensure sustainable mining practices.
Rock exploration in mines requires collaboration between geologists, geophysicists, geochemists, and
mining engineers. It is an iterative process that combines field observations, laboratory analysis, and
geological modeling to provide critical information for effective and responsible mining operations.
Rock Description Sequence
Here is the correct rock description sequence typically followed in mines:
Lithology: The lithology describes the overall rock type and composition encountered. It
includes the mineralogical composition, grain size, texture, and any distinctive features.
Examples of lithology descriptions include granite, sandstone, limestone, schist, etc.
Rock Structure: The rock structure refers to the internal arrangement and features within
the rock. It includes bedding planes, jointing, faulting, folding, and any other structural
elements observed. The orientation, spacing, and characteristics of these structures are
recorded.
Weathering and Alteration: The degree of weathering and alteration of the rock is
described. This includes the extent of physical and chemical weathering, such as
disintegration, color changes, and mineral decomposition. The presence of alteration
minerals and their distribution is noted.
Veins and Mineralization: Any veins, mineral deposits, or mineralization present within the
rock are documented. The type, thickness, mineral content, and distribution of these features
are described. This information is crucial for identifying potential mineral resources and
determining mining methods.
Geotechnical Properties: Geotechnical properties of the rock are assessed and recorded.
This includes the rock's strength, hardness, jointing frequency, orientation, and spacing, as
well as any other geotechnical parameters relevant to the mining operations. These properties

4. help evaluate rock stability, determine excavation methods, and design support systems.
Rock Quality Designation (RQD): RQD is a quantitative measure used to assess the quality
and continuity of intact rock within a borehole. It is determined by calculating the percentage
of core recovery with lengths greater than a specified threshold (usually 10 cm). RQD
provides an indication of the rock mass strength and can assist in slope stability assessments.
Rock Mass Rating (RMR) or Geotechnical Rock Mass Rating (GRMR): RMR or GRMR
is a numerical classification system used to evaluate the engineering properties of rock
masses. It considers parameters such as intact rock strength, rock quality, joint conditions,
groundwater conditions, and slope orientation. RMR or GRMR assists in assessing rock
mass stability and designing appropriate support measures.
Geological Observations: Any additional geological observations relevant to the specific
mine site, such as fossils, stratigraphic units, mineral textures, or other significant geological
features, are recorded.
The rock description sequence provides a comprehensive understanding of the rock conditions within a
mine and assists in mine planning, design, and decision-making processes. It helps geologists, engineers,
and mining professionals assess the geological and geotechnical aspects of the rock mass to ensure safe
and efficient mining operations.
Activity – 1 Explain Geotechnical exploration
Activity – 2 write down types of Geotechnical phases.
Success Criteria:
 Assessment plan
A couple of question will be asked from students to clarify the understanding of the whole class, for
example
 What do you understand by Resources of minerals in Pakistan?
 Discussion on Different techniques and its types of rocks.
C.W: Write down the Physical properties of Rock
H.W: Write On importance of Earths properties as a Rock Sequence.