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Dike swarms are ubiquitous on terrestrial planets and represent the frozen remnants of magma transport networks. However, spatial complexity, protracted emplacement history, and uneven surface exposure typically make it difficult to quantify patterns in dike swarms on different scales. In this study, we address this challenge using the Hough transform (HT) to objectively link dissected dike segments and analyze multiscale spatial structure in dike swarms. We apply this method to swarms of three scales: the Spanish Peaks, USA; the Columbia River Flood Basalt Group (CRBG), USA; the Deccan Traps Flood Basalts, India. First, we cluster dike segments in HT space, recognizing prevalent linearly aligned structures that represent single dikes or dike packets, with lengths up to 10 −  30x the mapped mean segment length. Second, we identify colinear and radial dike segment mesoscale structures within each data set, using the HT to segment swarms into constituent spatial patterns. We show that for both the CRBG and Deccan Traps, a single radial or circumferential swarm does not well characterize the data. Instead, multiple and sometimes overlapping mesoscale linear and radial features are prevalent suggesting a complex history of crustal stresses. The HT can provide useful insights in a variety of geologic settings where many quasi‐linear features, at any scale, are superimposed spatially. 

The morphology and distribution of volcanic edifices in volcanic terrains encodes the structure and evolution of underlying magma transport as well as surface processes that shape landforms. How magmatic construction and erosion interact on long timescales to sculpt these landscapes, however, remains poorly resolved. In the Cascades arc, distributed volcanic edifices mirror long-wavelength topography associated with underlying crustal magmatism and define the regional drainage divide. The resulting strong along- and across-arc modern precipitation gradients and extensive glaciation provide a natural laboratory for climate-volcano interactions. Here, we use 1,658 volcanic edifice boundaries to quantify volcano morphology at the arc-scale, and reconstruct primary edifice volumes to create first-order estimations of Cascades erosion throughout the Quaternary. Across-arc asymmetry in eroded volumes, mirroring similarly asymmetric spatial distribution of volcanism, suggests a coupling between magmatism and climate in which construction of topography enhances erosion by orographic precipitation and glaciers on million-year timescales. We demonstrate with a coupled landscape evolution and crustal stress model that mountain building associated with magmatism and subsequent orographically-induced erosion can redistribute surface loads and direct subsequent time-averaged magma ascent. This two-way coupling can thus contribute to Myr-scale spatial migration of volcanism observed in the Cascades and other arcs globally.