Archive for the ‘Geological Mapping’ Category

Fact, Truth and Scientific Method

Fact, Truth and Scientific Method

Is there such a thing as a geological “fact map”? Can we justify the widely used term “ground truth” to describe such a map, or indeed any direct geological field observation? This is not just a question of semantics. Surface indications of ore are usually subtle, and […]

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Sense of movement structures in fault zones Part 3: Identification Criteria

Sense of movement structures in fault zones  Part 3: Identification Criteria

Sense of Movement Structures in Fault Zones.  Part 3: Identification criteria Within or adjacent to a fault zone, various minor structures can be present that enable the sense of movement across the fault to be determined.  These structures are often called kinematic indicators. In Part 1 of […]

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Sense Of Movement Structures in Fault Zones: Part 2: Examples

Sense Of Movement Structures in Fault Zones: Part 2: Examples

Sense of Movement  Structures in Fault Zones :  Part 2 – Examples Within or adjacent to fault zones, various minor associated structures can be present that enable the sense of movement across the fault to be determined. These structures are often called kinematic indicators. This is the […]

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Sense of movement structures – Part 1, Theory

Sense of movement structures – Part 1, Theory

Sense of movement structures in fault zones - Part 1, Theory Within or adjacent to fault zones, various minor associated structures can be present that enable the sense of movement across the fault to be determined. These structures are often called kinematic indicators. Faults are the host to […]

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Drill Hole Targeting

Drill Hole Targeting

  TARGETING DRILL HOLES It is a truism that ore bodies are rare and hard to locate. If this were not so, they would hardly be worth finding.  Explorers search for them by drilling holes into the ground.  A single drill hole produces a very small sample […]

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Making Sense of 2-D Data : Part 2 – Folds

Making Sense of 2-D Data : Part 2 – Folds

MAKING SENSE OF 2D DATA – PART 2: FOLDS This post is the second of three parts and describes the different appearances which folds can have depending on the orientation of the surface on which they are exposed. Visualising complex objects in three dimensions isn’t easy, although […]

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Making sense of 2-D Data – Part 1: Faults

Making sense of 2-D Data – Part 1: Faults

Visualising complex objects in three dimensions isn’t easy, although geologists are better at this than most. Two dimensional objects are an order of magnitude easier to comprehend. Where the object under study is complex we can gain an understanding by visualising or portraying two dimensional slices across […]

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Is there such a thing as a geological fact map?

Is there such a thing as a geological fact map?

  Is there a sense in which a geological map can be described as a representation of fact? Can a map define “ground truth?” A map is a virtual reality representation of the world in two dimensions. A geological map is a human artefact constructed according to […]

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Map scales

Map scales

The most fundamental feature of any map is its scale. The scale of a map is the ratio of a length of a unit line on the map to the length that that line represents in the real world.   The ratio is expressed as a fraction that […]

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Geological Interpretation of Air Photo and Satellite Images

Geological Interpretation of Air Photo and Satellite Images

Air photographs (along with other similar remote sensed products such as satellite and radar imagery) provide both a mapping base on which to record field observations and an integrated view of landscape on which map-scale patterns of lithology and structure can be directly observed or interpreted.  Where […]

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