Block 1: Landscapes, Geological Maps, Strata, and Earth Processes

Comprehensive vocabulary flashcards covering the entirety of Block 1: Landscapes, Geological Maps, Strata, Weathering, and Geological Time.

Topography

The study and appearance of the land’s surface, especially its shape.

Landform

A distinctive natural feature of a planet’s solid surface, such as a hill or valley.

Geomorphology

The scientific study of landforms and the processes that create them.

Geosystem Services

Five distinct types of services provided by the Earth system: regulating, supporting, provisioning, cultural, and knowledge services.

Regulating Geosystem Services

Earth services that regulate natural processes, including water flow, flood management, atmospheric processes, and the carbon cycle.

Provisioning Geosystem Services

Geosystem services that supply material assets, such as geological resources, construction materials, and groundwater.

Landform Classification

The categorisation of landforms based on elevation, shape, orientation, slope, material, soil type, and rock exposure.

Positive, Negative, and Flat Landforms

Landform classifications based on elevation relative to regional terrain: positive is above, negative is below, and flat is at roughly the same elevation.

Erosion and Deposition

The two primary physical processes responsible for the formation of landforms.

Orders of Landforms

The spatial scale classification of landforms: first order (global), second order (regional), and third order (local).

Examples of Landform Orders

First-order landforms include continents and oceans; second-order include mountain ranges and plateaus; third-order include dunes, deltas, and meanders.

Erosion

The removal of material by natural processes such as water, wind, ice, or gravity.

Relief

The variation in the elevation of the land surface.

High Relief

Rapid changes in elevation over short distances, producing features such as mountains, cliffs, and gorges.

Tectonic Plate Collision Relief

High relief created when collision compresses, deforms, and thickens the crust, forming mountains and sometimes plateaus.

Volcanic Activity Relief

High relief generated as erupted material accumulates into volcanic rock, which subsequent erosion carves into deep valleys.

Long-Term Relief Evolution

The progressive wearing down of high-relief landscapes over millions of years; as elevation decreases, erosion generally slows and relief becomes more subdued.

Differential Erosion

The uneven removal of rock caused by differences in resistance among rock types, leading to some eroding faster than others.

Rock Resistance Relief Expression

The topographical pattern where hard rocks tend to form ridges and higher ground, while softer rocks tend to form valleys.

Scree

Loose rock fragments and debris that accumulate on a steep slope or at the base of a cliff.

Alluvium

Loose sediment deposited by running water, consisting of clay, silt, sand, and gravel.

Moraine

Rock, dirt, and sand transported and deposited directly by a glacier.

Rock Exposure

The proportion or extent of bedrock visible directly at the Earth’s surface.

Factors Influencing Rock Exposure

Environmental and geological controls including rock resistance, erosion rate, climate, and active volcanism.

Sill

A sheet-like igneous intrusion, often horizontal, emplaced between pre-existing rock layers.

Scarp

A steep slope where the ground surface cuts abruptly across rock strata.

Dendritic Drainage Pattern

A branching, tree-like river network that typically develops on relatively uniform geology lacking dominant structural control.

Trellis Drainage Pattern

A drainage pattern formed where inclined, alternating hard and soft rock layers produce alternating ridges and parallel linear valleys.

Radial Drainage Pattern

A drainage network where streams radiate outward in all directions from a central high point, such as a volcano or structural dome.

Centripetal Drainage Pattern

A drainage network in which streams converge inward toward a central low-lying basin or lake.

Annular Drainage Pattern

A roughly circular drainage network guided by concentric geological structures of differing erosional resistance.

Rectangular Drainage Pattern

A drainage pattern controlled by intersecting fault or joint sets, producing sharp right-angled bends.

Parallel Drainage Pattern

A drainage pattern characterised by streams flowing in similar directions down a consistently sloping regional surface.

Permeable Rock

Rock that permits water to transmit through interconnected pores or open fractures.

Impermeable Rock

Rock that does not permit water to pass through easily.

Karst

A landscape formed by the chemical dissolution of soluble bedrock, producing features such as caves, sinkholes, and limestone pavements.

Karst Bedrock

Soluble rocks prone to chemical dissolution, predominantly limestone.

Springline

A line of groundwater emergence formed where a permeable rock layer overlies an impermeable rock layer.

Plant Growth Determinants

The primary environmental requirements governing plant development: light, temperature, water, and nutrients.

Geological Influence on Soil and Vegetation

Weathered bedrock supplies essential mineral content to soil, while bedrock permeability governs drainage and soil moisture conditions.

Topographic Representation Methods

The main cartographic techniques for depicting land relief: shaded relief, contour lines, aerial/satellite imagery, and colour-banded digital elevation models (DEMs).

Raster Image

A digital image composed of a grid of pixels, whose resolution is typically measured in pixels per inch (ppi).

Raster Pixelation

The visual degradation and blurring that occurs when a raster image is magnified beyond its native resolution.

Vector Data

Geospatial data represented by points, lines, and polygons that maintain clarity and scale smoothly at any zoom level.

Raster vs. Vector Data

Raster data has a fixed resolution suited for continuous surfaces, whereas vector data scales smoothly and is ideal for discrete features.

Mercator Projection Distortion

A map distortion whereby geographic areas become progressively exaggerated in size with increasing distance from the equator.

Mercator Projection Navigation Utility

A conformal property that preserves angles, allowing navigators to plot constant compass bearings as straight lines.

Latitude and Longitude

A global geographic coordinate system used to pinpoint precise locations on the Earth's surface.

Delta

A depositional landform created where a river carrying sediment enters a body of standing water, depositing material faster than waves and currents can remove it.

Delta Vulnerability

The susceptibility of deltas to sea-level rise due to their low elevation and continuous subsidence driven by sediment weight.

Cryogenic Landform or Process

A geomorphic landform or physical process associated directly with naturally occurring ice and the cryosphere.

Biogenic

Originating from, created by, or produced by living organisms.

Rock Resistance Factors

Properties governing a rock’s durability against erosion: age, rock type, mineral composition, degree of cementation, and planes of weakness.

Mohs Scale

A qualitative comparative scale used to classify the relative scratch resistance and hardness of minerals.

Silicate Mineral Hardness

The physical durability of silicates resulting from crystalline frameworks held together by strongly bonded silicon and oxygen atoms.

Clay and Mica Softness

The relative weakness of clay minerals and micas caused by internal planes of weakness within their atomic sheet structures.

Carbonate Weathering Vulnerability

The chemical susceptibility of calcite and related carbonates due to their low hardness and solubility in slightly acidic rainwater.

Sandstone Cementation Effect

The control of sedimentary durability by the matrix cement; strong, resistant cement yields durable sandstone, whereas weak or soluble cement promotes erosion.

Bedding Planes

Planar surfaces separating distinct beds of sedimentary rock, typically representing pauses or changes in depositional conditions.

Joints

Systematic fractures in rock without significant displacement, which concentrate weathering and accelerate erosional processes.

Strata

Sedimentary or volcanic rock layers deposited successively in a chronological sequence.

Dip and Strike

Dip is the angle and inclination direction of an inclined rock bed relative to horizontal; strike is the compass bearing of a horizontal line on the bedding surface.

Arête

A knife-edge, narrow ridge of rock formed between two adjacent glaciated cirques.

Drumlin

A smooth, elongated, tear-drop-shaped hill composed of glacial till/moraine shaped by moving ice.

Tombolo

A depositional spit or ridge of sand and sediment connecting an offshore island to the mainland or to another island.

Oxbow Lake

A crescent-shaped lake formed when a meandering river breaches a narrow meander neck, abandoning the former channel loop.

Geological Controls on Skye

The landscape variation of the Isle of Skye produced by contrasting rock types exhibiting differential resistance to weathering and erosion.

Basaltic Lava Flow Landscape (Skye)

Extensive moorland plateaux with stepped, terraced escarpments, forming classic layer-cake topography.

Gabbro Landscape (Skye)

A rugged terrain of jagged, sharp ridges, precipitous rock walls, and extensive talus and scree slopes.

Granite Landscape (Skye)

Smooth, rounded hills and mountains with upper slopes commonly mantled in weathered coarse granitic gravel.

Sedimentary Rock Landscape (Skye)

Low-lying, rolling topography with gentle slopes and infrequent rock exposures due to the softness of the rocks.

Geological Map

A specialised thematic map portraying the spatial distribution, rock types, and ages of bedrock and superficial materials exposed at the surface.

Rock Exposure Data Collection

The recording of lithological composition, fossil assemblage, and internal structural orientations from exposed bedrock.

Unexposed Geology Interpretation

Inferring underlying bedrock where exposure is absent by evaluating soil characteristics, landforms, borehole logs, and satellite imagery.

Geological Boundary Symbols

Solid lines represent accurately observed geological contacts, whereas dashed lines denote inferred or uncertain contacts.

Geological Map Legend

The explanatory reference table defining map colours, stratigraphic symbols, fault notations, and structural markings.

Geological Cross-Section

A profile diagram illustrating the observed and projected geological structure beneath the ground along a specified transect.

Geographic Information System (GIS)

An integrated system of computer hardware, software, geospatial data, and personnel designed to capture, manage, and analyse spatial information.

GIS Spatial Relationships

Topological and spatial relationships analysed by GIS, specifically adjacency, containment, proximity, and temporal changes.

Web GIS Advantages

Cross-device accessibility, centralised real-time updates, collaborative sharing, and minimal local data storage requirements.

Web GIS Disadvantages

Potential reductions in analytical functionality compared to desktop installations, and total dependence on active internet connectivity.

Principle of Superposition

A fundamental stratigraphic law stating that in an undeformed sedimentary sequence, the oldest stratum is at the base and the youngest is at the top.

Borehole

A narrow shaft drilled vertically or inclined into the ground to retrieve core samples and assess subsurface lithology.

Stratigraphic Sequence Disruptions

Geological events that interrupt normal stratification: tectonic collision, subduction, faulting, uplift, erosion, metamorphism, magmatic melting, and sea-level fluctuations.

Outlier

An isolated outcrop of younger rock completely surrounded by older rock strata.

Inlier

An isolated exposure of older rock completely surrounded by younger rock strata.

Unconformity

A structural contact separating two rock sequences representing an interval of non-deposition, weathering, or erosion in the geological record.

Angular Unconformity

An unconformity in which horizontally layered younger strata overlie older strata that are tilted or folded, exhibiting discordant dip angles.

Angular Unconformity Sequence

The multi-stage geological history: initial deposition → tectonic deformation or tilting → regional uplift and erosion → renewed sediment deposition → burial and lithification.

Unconformity Field Evidence

The visual identification of an erosional surface truncating underlying strata of contrasting age and bedding dip.

Geological Exposure Field Documentation

The two mandatory contextual parameters required when documenting any outcrop: spatial orientation (compass direction) and visual scale.

Fault

A planar fracture or zone of weakness in rock along which measurable shear displacement has occurred.

Normal Fault

A dip-slip fault formed under crustal tension (extension) where the hanging wall drops downward relative to the footwall.

Thrust Fault

A low-angle reverse fault dipping at less than $30^\circ$, formed by crustal compression that drives the hanging wall upward over the footwall.

Transform (Strike-Slip) Fault

A fault where opposing crustal blocks slide past each other horizontally with predominantly strike-parallel displacement.

Thrust Fault Tectonic Environment

Compressional mountain belts characterised by significant horizontal crustal shortening, crustal thickening, and intense folding.

Superficial Deposits

Unconsolidated, modern geological materials mantling bedrock, including river gravels, glacial till, alluvium, peat, and coastal sand.

Adit

A horizontal or near-horizontal underground passage driven into a hillside to provide access to or drainage for a mine.

Historical Quarry Resources

Surface materials targeted by early quarries: building limestone, flint for tools, ochre pigments, and bulk gravels or conglomerates.

Modern Borehole Uses

Contemporary drilling applications: groundwater abstraction, geothermal energy extraction, mineral exploration, geotechnical site appraisal, environmental monitoring, and carbon capture storage.