Arda was known to exhibit two distinct conditions of form. In the earliest annals the earth lay extended and level, but thereafter a single mighty transmutation gave it the rounded aspect recorded in later lore. The position of land and sea therefore resulted from combined operations of wide uplift and subsidence, local fracture and folding, the emplacement of igneous masses, and protracted processes of waste and deposition. These categories served as a practical schema for the description of provinces and occurrences, and required no mystical gloss to their employment.
Principal Upheavals and Their Effects[]
The great Transformation stood forth as the central orographic fact. It altered shores, opened deep basins of the sea, submerged broad tracts of country, and established new contrasts of height. In subsequent ages wide uplifts formed mountain tracts, while confined subsidences desolated whole realms; among the most conspicuous examples were the sinking of Beleriand and the overthrow of Númenor. Lines of fracture produced steep escarpments, narrow gorges, and linear valleys; these features gathered erosion and the transport of detritus and frequently marked the courses of ancient roads and the bounds of lordships.
Volcanic and plutonic energies acted in particular regions. The work of such forces displayed itself in basaltic flats, in islands born of fire, and in hard intrusive masses which furnished both building stone and ore. The conjoint action of sudden reconfiguration and gradual modification impressed upon Arda a physiognomy more decided than could have been achieved by slow uniform change alone.
Character of the Several Regions[]
Aman and its coasts remained comparatively tranquil after the Transformation. Their shores reclined upon terraces, and the continental shelf thereabouts was broad; tectonic displacements were moderate. Beleriand formerly comprised extensive lowlands, riverine deltas and coastal lagoons; after its submergence it showed only archipelago and drowned shelf, with shifting bars and shallows.
The west of Middle-earth exhibited rolling lowlands, trenched river valleys, and detached mountain outliers such as the Blue Mountains. Those lands supplied wide alluvial plains and fertile soils, while veins of ore appeared at the margins of older intrusive masses. Rhovanion and the eastern districts contained larger mountainous systems, broad plains, and more complex fluvial nets; their orographic contrasts determined wide divergences of precipitation, vegetation, and uses of the soil.
Númenor bore a central upland and terraced coasts; its sudden ruin left submerged relief and maritime shallows. Along the coasts of Arda the forms varied from sheer cliff to ample shelf, much of their present aspect being the direct outcome of the great upheavals and the later play of marine and fluviatile forces.
Climate, Waters, and the Work of Ice[]
Chains of mountains acted as principal watersheds and governed the distribution of rain by the well-known orographic effect. Elevation produced tracts of enhanced moisture and deep, sheltered valleys; the leeward sides of these barriers were commonly dry. The rearrangement of ocean basins altered currents and thereby affected coastal climate and the modes of sedimentary accumulation. Rivers, responding to crustal movement, changed course by avulsion, cut gorges, and built deltas; their alluvia formed fertile territories and extended littoral flats.
In the higher latitudes and upon great mountain masses ice and glacier were operative. The action of glaciers carved broad U-shaped valleys, left morainic accumulations and transported vast quantities of detritus. These glacial vestiges furnished important testimony for the reconstruction of cooler and moister epochs in Arda's annals.
Mineral Resources and mannish Employ[]
Metals and jewels were chiefly found where intrusive bodies met older metamorphic belts. Veins formed by pegmatitic and hydrothermal processes yielded rare and precious substances which acquired high esteem. Durable stones, sandstones and limestones determined building practice in the several lands. The situation of mines and quarries shaped the foundations of towns, the courses of commerce, and the seats of power; when rich fields were lost beneath the sea or wasted by time, the balance of polity was commonly disturbed.
Sunken coasts altered the convenience of harbours and the direction of trade; many ancient works of men lay buried beneath marine mud or survived only as shoals and reef-strewn shallows.
Processes of Change and a Practical Chronology[]
The face of Arda was fashioned by a union of discrete cataclysms and long-continued agencies. Chief among the processes were the wearing of rock by rivers and wind, slope failures on steep faces, the shifting of coasts by erosion and deposition, and the steady accumulation of sediment in mouths of rivers and on the continental shelf. For convenience of study the history of these changes was divided into three stages: the pre-Transformation condition, the Transformation and its immediate consequences, and the long-continued evolution that followed. Forms of the land supplied the principal means of dating and of restoring former shorelines, though in many districts precise chronological discrimination remained beyond reach.
The Westlands[]
This map shows the predominant rock types underlying the lands of northwestern Middle-earth, as well as major deposits of significant minerals.
References[]
- MERP:Northwestern Middle-Earth Campaign Atlas
- MERP:Northwestern Middle-Earth Gazetteer
Editorial Note: This entry contains speculative or fan-based material — such as fanon, fanfiction, or theory constructs — that may not be directly supported by canonical texts. Interpretations offered here are part of the NNCA’s speculative corpus and should not be mistaken for primary Tolkien sources.