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Tweed Volcano

Tweed Volcano is an extinct shield volcano spanning northeastern New South Wales and southeastern Queensland, Australia, with a diameter of approximately 100 km and centered on the Mount Warning volcanic plug.^[1] Formed around 23 million years ago during the Early Miocene as the Indo-Australian plate moved over a mantle hotspot, it erupted for about three million years, building a massive dome-shaped structure that rose over 2 km above sea level through successive flows of basalt and rhyolite lavas.^[2] The volcano's activity occurred in three main phases: initial basaltic eruptions forming the Beechmont and Lismore flows, followed by explosive rhyolitic activity that contributed to caldera formation, and concluding with quieter basaltic phases like the Blue Knob and Hobwee flows.^[2] Today, heavily eroded over the past 20 million years, it exposes the largest erosion caldera in the Southern Hemisphere, exceeding 40 km in width and 1,000 m in depth, encompassing fertile landscapes, radial ridges, deep valleys, and notable features such as columnar basalts at Fingal Head and rhyolitic gorges in Lamington National Park.^[3] As part of the ancient Eastern Australian hotspot chain, Tweed Volcano represents a key geological formation that influenced regional biodiversity and soil fertility, now recognized as a Landscape of National Significance known as "Australia's Green Cauldron."^[2]^[3]

Location and geography

Coordinates and extent

The Tweed Volcano is centered at approximately 28°24′S 153°16′E, with Mount Warning (Wollumbin) marking the central volcanic plug that represents the remnant summit of the ancient shield. This position places the volcano in the far northeastern corner of New South Wales, Australia, near the border with Queensland.^[2] Originally, the shield volcano extended across approximately 100 km in diameter, encompassing a broad volcanic pile that spanned northeastern New South Wales and southeastern Queensland, from areas near Lismore in the south to Tamborine in the north.^[4] Its lavas and associated features influenced a wide region, contributing to the formation of surrounding plateaus and ranges. Extensive erosion over millions of years has shaped the modern boundaries into an erosion caldera approximately 40 km in diameter, forming the fertile Tweed Valley that straddles the New South Wales-Queensland border.^[3] This caldera is bounded by steep escarpments and is integral to the local geography, with the volcano's remnants integrated into the Great Dividing Range, particularly influencing the McPherson and Tweed Ranges that define much of the regional topography.^[2]

Topography and surrounding features

The Tweed Volcano, now heavily eroded, features a prominent central remnant in the form of Mount Warning (also known as Wollumbin), which stands as the highest point at 1,156 meters above sea level and represents the exposed volcanic plug of the ancient shield volcano.^[5] This rugged peak rises sharply from the surrounding landscape, forming a distinctive erosional caldera that defines the regional topography. Prior to extensive erosion over millions of years, the volcano is estimated to have reached heights of up to 2 kilometers, creating a broad shield structure that dominated the northeastern New South Wales and southeastern Queensland skyline.^[6]^[2] The volcano's topography is characterized by radial drainage patterns and elevated erosional remnants that form surrounding plateaus and ranges. To the north lie the Lamington and Springbrook Plateaus, while the Border Ranges and McPherson Range extend westward and northwestward, with the Nightcap Range bordering to the south; these features are the dissected remnants of the original volcanic edifice, capped by resistant basalt layers and dropping to lower valleys through steep escarpments.^[2] The Tweed River originates within the caldera, flowing eastward from the slopes near Mount Warning through deep gorges and fertile valleys before reaching the Pacific Ocean, its course shaped by the volcano's post-eruptive dissection.^[5]^[2] The volcanic soils derived from the eroded basalt and associated materials are notably fertile, supporting extensive agriculture in the Tweed Valley, including major crops such as sugarcane, bananas, and other subtropical fruits, as well as cattle grazing.^[2] This alluvial enrichment, combined with high rainfall in the elevated terrains, has fostered productive floodplains along the river system, contrasting with the rugged, forested highlands of the surrounding ranges.^[5]

Geological history

Age and formation

The Tweed Volcano, also known as the Tweed Shield Volcano, originated in the Early Miocene epoch, with volcanic activity commencing approximately 23 million years ago (Ma).^[2] Rock dating methods, including radiometric analyses, confirm that the initial eruptions marked the volcano's emergence as part of a broader Cenozoic volcanic track in eastern Australia.^[7] This timing aligns with the northernmost position in a chain of central volcanoes formed as the Indo-Australian plate migrated over a mantle hotspot.^[2] The formation process began with hotspot-driven magmatism, leading to the development of a shield volcano characterized by effusive basaltic eruptions that built a broad, dome-shaped structure.^[2] These low-viscosity lavas flowed extensively over a wide area, accumulating to form low-angle slopes typical of shield volcanoes, with the edifice eventually reaching over 2 kilometers in height and spanning from present-day Lismore in the south to Tamborine in the north.^[2] The hotspot origin facilitated prolonged magma ascent through a thinned lithosphere, enabling the initial constructive phase dominated by fluid basaltic outflows rather than explosive events.^[8] Volcanic activity persisted for about 2 to 3 million years, encompassing a continuous shield-building phase of effusive eruptions followed by more explosive rhyolitic events toward the conclusion of the cycle.^[7]^[2] Recent geochronology indicates activity from approximately 24 to 20 Ma.^[9] This duration is evidenced by stratigraphic sequences showing multiple lava flow phases at irregular intervals.^[2] The transition to rhyolitic activity likely reflected crustal differentiation and volatile accumulation, marking the volcano's evolution from dominantly effusive to intermittently explosive before quiescence.^[9]

Tectonic setting

The Tweed Volcano is part of the East Australian hotspot chain, a extensive volcanic province extending along the eastern margin of the continent, and is closely linked to the North Queensland volcanic province.^[8] This chain represents the longest continental hotspot track on Earth, spanning over 2,000 kilometers from northern Queensland to southern Victoria, formed by volcanic activity over the past 35 million years.^[10] The volcano itself developed as a prominent shield structure within this sequence, associated with the Comboyne hotspot track that includes the adjacent Main Range province.^[8] In the broader regional context, the Tweed Volcano's formation occurred during the late stages of Gondwana's breakup and the associated rifting of the Coral Sea basin, which initiated around 90 million years ago and continued influencing eastern Australian tectonics into the Cenozoic era.^[2] As the Indo-Australian Plate drifted northward at approximately 7 centimeters per year, it passed over a fixed mantle hotspot, triggering intraplate volcanism unrelated to subduction or continental collision.^[10] This plate motion positioned the Tweed region directly above the hotspot during the early Miocene, approximately 23 million years ago, enabling prolonged magmatic upwelling.^[2] The driving mechanism for the volcano's development was an upwelling mantle plume beneath the Indo-Australian Plate, a deep-seated thermal anomaly that generated basaltic melts through decompression melting in the asthenosphere.^[8] This plume dynamics mirror those responsible for other Miocene volcanic features in the eastern Australian hotspot chain.^[8] Paleomagnetic evidence indicates that these hotspots have remained largely stationary relative to the Earth's spin axis, with any minor southward drift (less than 370 kilometers over 30 million years) consistent with global true polar wander rather than plume migration.^[8] The Tweed Volcano precedes younger manifestations of the hotspot chain, such as the Mount Gambier volcanic province in South Australia, which erupted around 5 million years ago as the plate continued its northward progression.^[10] Consequently, the Tweed region has experienced no volcanic activity for over 20 million years, as it has long since moved away from the underlying hotspot, leaving the plume to influence more southerly locations.^[2]

Volcanic features

Type and eruptive style

Tweed Volcano is classified as a shield volcano, characterized by its broad, gently sloping flanks formed primarily through the accumulation of fluid basaltic lava flows. This morphology resulted in a low-profile dome structure, with the original edifice spanning approximately 100 km in diameter and rising over 2 km above sea level before extensive erosion.^[2]^[11] The eruptive style of Tweed Volcano was predominantly effusive during its early and late stages, involving the outpouring of basaltic lavas that covered vast areas of the surrounding landscape. These phases produced extensive lava flows, such as the Beechmont and Lismore basalts initially, followed by quieter Blue Knob and Hobwee flows toward the end. In contrast, an intermediate phase featured more explosive activity, with violent eruptions of rhyolitic magma that ejected volcanic glass, agglomerates, and ash, contributing to the formation of tuffs and deeper gorges, with the overall caldera structure resulting from subsequent erosion.^[2]^[12] Overall, the volcano is estimated to have erupted approximately 4,000 km³ of material over its approximately 1.2-million-year active period (ca. 24.3–23.1 Ma), building a structure similar to classic Hawaiian shield volcanoes but distinguished by explosive events driven by felsic magmas.^[13]^[11]^[14]

Magma composition

The magmas erupted by Tweed Volcano are predominantly tholeiitic basalts, characterized by relatively low potassium and silica contents compared to other series, with subordinate calc-alkaline basalts exhibiting higher aluminum and alkali enrichment. Later stages include minor alkaline basalts, transitional in composition and marking a shift toward more undersaturated, potassic melts. These primary mafic compositions reflect derivation from partial melting of mantle sources beneath a continental hotspot.^[15]^[16] Felsic components, primarily rhyolites, comprise a significant portion of the volcanic succession and indicate extensive magma differentiation coupled with crustal interaction, as evidenced by elevated radiogenic strontium isotope ratios (e.g., high ^{87}Sr/^{86}Sr values). These rhyolites formed through processes such as partial melting of the lower crust or assimilation of continental material by ascending mafic magmas. Mineralogically, the basalts feature phenocrysts and groundmass of olivine, clinopyroxene (often augite), plagioclase (typically labradorite to bytownite), and opaque oxides like magnetite, with variable amounts of interstitial glass. In contrast, rhyolites are dominated by quartz and alkali feldspar (sanidine or orthoclase) phenocrysts, accompanied by minor plagioclase and accessory phases such as biotite or hornblende.^[13]^[17]^[13] Magma evolution at Tweed Volcano began with primitive mafic hotspot melts from the asthenospheric mantle, which underwent fractional crystallization—primarily of olivine, pyroxene, and plagioclase—to produce more evolved compositions. This process, combined with magma mixing and crustal assimilation, led to the generation of siliceous magmas, as demonstrated by trace element trends (e.g., increasing incompatible elements like Zr and Nb) and isotopic signatures indicating up to 20-30% crustal contribution in felsic units. Such evolution contributed to varied eruptive styles, with mafic compositions favoring effusive flows and felsic ones promoting explosive activity.^[13]^[18]^[15]

Stratigraphy

Basaltic units

The basaltic units of the Tweed Volcano form the primary effusive components of its volcanic sequence, consisting of extensive sheet-like lava flows that built the foundational shield structure. These units comprise two main phases: lower/early and upper/late series, with a total distribution covering an approximately 80 by 100 km area across northeastern New South Wales and southeastern Queensland. The flows exhibit predominantly tholeiitic compositions, with variations toward transitional and mildly alkaline affinities in higher units, and were erupted during the Early Miocene between roughly 24.3 and 23.1 Ma.^[19] The Lower/Early Series comprises the Lismore Basalt in the southern portion and its equivalents, such as the Beechmont Basalt to the north, representing thick tholeiitic flows that established the shield base. These basalts are predominantly tholeiitic andesites with minor icelandite and sporadic mildly alkaline variants, forming multiple thin flows rarely exceeding 10 m in individual thickness but accumulating to significant volumes as the initial volcanic pile.^[20]^[18] Capping the sequence after the intervening rhyolitic phase, the Upper/Late Series consists of the Blue Knob Basalt in the south and the Hobwee Basalt in the north, characterized by alkalic traits within an overall tholeiitic andesite composition, including olivine- or quartz-normative varieties with plagioclase and rare augite phenocrysts. These flows reach up to 350 m thick in places, such as at Blue Knob, where they overlie earlier units and form prominent plateau caps on ranges like the Nightcap and McPherson.^[18]^[21]^[17]

Rhyolitic units

The rhyolitic units of the Tweed Volcano represent the felsic volcanic rocks erupted during the early Miocene, primarily as lava domes, flows, and minor pyroclastic deposits, marking a shift to more evolved magma compositions within the shield volcano's stratigraphy.^[22] These units overlie earlier basaltic formations and reflect advanced differentiation processes in the underlying magma chamber.^[23] The Nimbin Rhyolite, exposed primarily in northeastern New South Wales, consists of a complex of coalescing rhyolite lava domes and flows erupted on the volcano's flanks.^[22] These are characterized by flow-banded textures, with crystal-poor varieties containing less than 5 vol.% phenocrysts and crystal-rich variants holding 10-30 vol.%, including quartz, sanidine, plagioclase, orthopyroxene, minor clinopyroxene, and ilmenite.^[22] A minor pyroclastic component, mainly lapilli tuff, accompanies the flows.^[20] The unit formed through fractionation of basaltic parent magmas, leading to highly siliceous compositions, with subsequent thermal rejuvenation from mafic inputs raising pre-eruptive temperatures by approximately 100°C and enabling effusive emplacement of degassed lavas up to 5 km from vents.^[22]^[23] The Binna Burra Rhyolite, its equivalent on the Queensland side, comprises potassic, two-feldspar rhyolite flows and associated deposits in the northern sector of the volcano.^[20] It features highly fractionated trace elements, such as low K/Rb ratios below 100 and depletions in Eu, Ba, and Sr alongside enrichments in Rb, U, and Th, with phenocrysts of quartz, sanidine, oligoclase, ilmenite, and rare Fe-rich fluor-biotite equilibrating at 800–950°C.^[23] This unit, representing about 7 vol.% of the Tweed Shield's total volume, also results from extensive differentiation of basaltic magmas at the quartz-feldspar minimum, with intercalated basaltic layers indicating episodic mafic recharge.^[23] Collectively, these rhyolitic units reach thicknesses up to 500 m in the Nimbin area, with individual flows attaining 100 m, though thinner sections around 100 m occur in the Springbrook portion of the Binna Burra Rhyolite; they are concentrated along the margins of the Tweed erosion caldera, covering approximately 400 km² in the central and northern regions.^[22]^[24] The compositional evolution from underlying basalts to these rhyolites underscores progressive magma chamber differentiation, culminating in viscous, siliceous melts prone to dome formation and localized explosive venting.^[23]

Intrusive complex

The Mount Warning Complex represents the plutonic core of the Tweed Volcano, exposed as a rugged central plug rising to 1,156 m above sea level and encompassing an elliptical area approximately 5.5 by 8 km. This intrusive body primarily consists of a central mass of syenite surrounded by a band of gabbroic rocks, with an inner core of trachyandesite; associated features include monzonite stocks and a prominent syenitic ring dyke along the western margin.^[25] Granitic intrusions and microsyenite dykes further characterize the complex, forming part of a broader network of stocks and swarms concentrated in the central 10–15 km zone.^[4] The composition of these intrusives is predominantly alkaline, featuring minerals such as nepheline and alkali feldspars, which reflect fractionated, late-stage magmatic processes within the volcano's evolution.^[4] Gabbros exhibit evidence of in situ crystal fractionation, while the syenites indicate prior differentiation before emplacement, highlighting independent pathways for intrusive and extrusive magmas.^[4] These rocks intrude into older volcanic and sedimentary country rocks, with chilling textures observed at contacts, underscoring rapid cooling against the host materials.^[25] Extensive erosion has unmasked the intrusive complex, stripping away the overlying volcanic pile to reveal its internal structure and relations to the broader shield.^[25] The complex served as a feeder system for the surface volcanics of the Tweed Volcano, including basaltic and rhyolitic units, during its Miocene activity.^[4]

Erosion and landscape evolution

Caldera development

Following the cessation of volcanic activity around 20 million years ago, the Tweed Volcano underwent profound erosional modification through differential weathering and denudation processes. Over this period, approximately 1,500–2,000 meters of the upper volcanic edifice were removed, primarily from the eastern and northern flanks, resulting in the formation of the expansive Tweed erosion caldera.^[13]^[2] The dominant erosional mechanisms involved fluvial incision by radial drainage systems and mass-wasting events, which selectively targeted less resistant lithologies such as basaltic flows and tuffs while preserving more durable rhyolitic domes and intrusions. This differential erosion hollowed out the central region, exploiting structural weaknesses to carve a broad basin approximately 40 kilometers in diameter.^[7]^[3]^[18] Recognized as the largest erosion caldera in the Southern Hemisphere, the Tweed structure exceeds 1,000 meters in depth from rim to floor, surpassing the relief of many intact igneous calderas worldwide.^[13]^[26] The region's persistently high annual rainfall, often exceeding 2,000 millimeters in upland areas, has significantly intensified these fluvial and gravitational processes, facilitating the deep dissection observed over the ensuing 20 million years.^[27]^[2]

Preserved remnants

The preserved remnants of the Tweed Volcano include several prominent volcanic plugs and landforms that represent the surviving core and peripheral features of the ancient shield volcano. Mount Warning, standing at 1,159 meters, is the most iconic remnant, forming the central volcanic plug that exposes the solidified magma chamber of the volcano's summit.^[2] In the Currumbin Valley, additional plugs such as Pinnacle and Dinsey Rock reveal secondary vents and dykes that intruded into the surrounding rocks during the volcano's activity.^[2] Along the coast at Fingal Head, columnar basalts from the Tweed lavas form distinctive hexagonal columns, resulting from the cooling of thick basalt flows that reached the ancient shoreline approximately 23 million years ago.^[28] The high plateaus surrounding the caldera, such as Springbrook and Lamington, persist as basalt-capped mesas that preserve thick sequences of the volcano's lava flows. These plateaus, part of the northern flank of the Tweed Volcano, reach elevations up to around 900 meters on Springbrook and over 1,100 meters along the McPherson Range crest in Lamington, where the resistant basalt layers protect underlying rhyolitic and sedimentary rocks.^[29]^[30] These features expose stratigraphic units including basaltic lavas and associated pyroclastics, as detailed in broader stratigraphic studies of the region.^[2] Preservation is uneven across the volcano's extent, with notable gaps in the westerly sections, such as the area between Mount Burrell in the Nightcap Range and Lofts Pinnacle in the Tweed Range, where fewer volcanic remnants occur due to underlying softer substrates.^[2] Geological exposures further highlight these remnants, particularly at sites like Mount Cougal, where road cuts and cliffs provide clear views of the volcano's internal structure, including layered basalts and intrusive elements.^[2]

References

[1]
Tweed Volcano Group, Australia - Mindat
Aug 8, 2025 · The Tweed volcano is a 100km diameter shield volcano spanning the border of Queensland and New South Wales. The earlier Focal Peak shield ...
[2]
Geological history - Tweed Regional Museum - NSW Government
Over a period of 3 million years, a vast dome shaped shield volcano was formed, towering over 2 km above sea level and stretching from Lismore in the south to ...
[3]
Tweed Extinct Volcano, Australia, Stereo Pair of SRTM Shaded ...
Jan 6, 2005 · Australia is the only continent without any current volcanic activity, but it hosts one of the world's largest extinct volcanoes, the Tweed ...
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Caldera - Big Volcano
Jan 3, 2025 · Brief description of the Tweed Volcano (big volcanoe) and caldera, and links to additional Australian volcano reseources.
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The Tweed and Focal Peak shield volcanoes ... - UQ eSpace
The Tweed and Focal Peak shield volcanoes are two overlapping volcanoes of Late Oligocene-Early Miocene age, forming mountainous country in southeast ...Missing: scientific | Show results with:scientific
[6]
Mt Warning Volcano, Australia | John Seach
Mt Warning volcano has a 30 km diameter erosion cladera. The original volcano height of Tweed volcano was 1900 m and it erupted 3200 sq km of lava. Contrary ...Missing: extent | Show results with:extent
[7]
Tweed | NSW Government Water
The highest point of the catchment is Mount Warning, at 1,156 metres. The Tweed River originates on the slopes of the nearby Mount Bushell, and flows north ...
[8]
Nature, culture and history | Tamborine National Park - QLD Parks
By the time the eruptions had ceased, this Tweed Volcano had risen to a height of 2km and a diameter of about 100km, forming a vast dome stretching south to ...Missing: original | Show results with:original
[9]
Warrumbungle Volcano: facies architecture and evolution of a ...
The central volcanoes of NSW are late Oligocene to Miocene age (ca 24–12 Ma), young from north to south and include Tweed, Ebor–Dorrigo, Nandewar, Comboyne, ...
[10]
NSW Volcanoes: Smaller, Shorter Lifetimes, Complex Eruptions
Mar 23, 2023 · The tipping point occurred at the stunning Tweed-Wollumbin (Mount Warning) volcanic landscape, which formed 21–24 million years ago at today's ...
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http://volcanolive.com/tweed.html
[12]
https://keckgeology.org/2019/01/texas2019/
[13]
Rhyolitic eruptions - Keck Geology Consortium
Jan 3, 2019 · The Tweed volcanic center has been the main research site for our structural analysis of flow-related textures over the past decade. The heavy ...
[14]
[PDF] Magmatic and Geodynamic Constraints on Cenozoic ... - UQ eSpace
Northern flank of Tweed -the most prominent shield volcano in east Australian Cenozoic volcanic province. Page 97. 78. ABSTRACT. Tweed is the largest (4000 km3) ...
[15]
The magmatic affinities of some volcanic rocks from the Tweed ...
May 1, 2009 · Many of the Tweed volcanic rocks are more potassic than similar rocks in other tholeiitic sequences. The likelihood of differing lineages in the ...
[16]
Tholeiitic andesite of high-pressure origin from the tweed shield ...
Abstract. A high-alumina tholeiitic andesite from the southern portion of the Tweed Shield Volcano in northeastern New South Wales contains abundant megacrysts ...Missing: paper | Show results with:paper
[17]
[PDF] Untitled - Research UNE (RUNE)
This major shield structure has a diameter of about 100 km and consists of a volcanic pile of up to 1000 m of basaltic, andesitic and rhyolitic eruptives.<|separator|>
[18]
[PDF] PAPERS Department of Geology - University of Queensland
The Tweed Shield Volcano, centred on the plutonic complex of. Mount Warning, comprises the Beechmont and Hobwee Basalts, their equivalents on the southern side ...
[19]
[PDF] 1. INTRO 2. REVIEW - Your Say Tweed
The caldera rim is formed by a sequence of basaltic, andesitic and rhyolitic volcanic rocks extending up from the Kyogle Basalt of the Focal Peak Group to the ...
[20]
(PDF) Cenozoic Volcanism in New South Wales - ResearchGate
Oct 21, 2022 · Cenozoic volcanism in New South Wales is both common place and voluminous. In recent years, paleo volcanoes and volcanic provinces have been ...<|control11|><|separator|>
[21]
Stratigraphy of the Lamington Volcanics in far Northeastern New ...
The stratigraphic nomenclature for the Lamington Volcanics in the southern part of the Tweed Shield Volcano is revised. An alkaline formation (the Kyogle.
[22]
Petrology and isotope geochemistry of tertiary lavas ... - UQ eSpace
The generalized stratigraphic sequence (20-21.8 m.y.) of the northern flank of the Tweed Volcano is: Beechmont Basalt (base)-Rhyolite (composed of two ...
[23]
https://academic.oup.com/petrology/article-pdf/18/1/73/4353029/18-1-73.pdf
[24]
https://pmc.ncbi.nlm.nih.gov/articles/PMC11800080/
[25]
Petrology and Isotope Geochemistry of Tertiary Lavas from the ...
ABSTRACT. The generalized stratigraphic sequence (20-21-8 m.y.) of the northern flank of the Tweed. Volcano is: Beechmont Basalt (base)—Rhyolite (composed ...
[26]
Determination of radon source in basaltic groundwater, using ...
Jan 10, 2025 · The Tweed Volcano is considered the largest and best-preserved basaltic shield-type volcano in Australia. The numerous lava flows were mostly ...
[27]
SH5602 Warwick , SH5603 Tweed Heads
ABSTRACT: The metallogenic study covers the Warwick-Tweed Heads 1:250 00 sheet area in northeastern NSW and southeastern Queensland.Missing: et al.
[28]
Springbrook, the focus of the rainforest restoration project, is a ...
This erosion caldera, about 30 km across, is one of the major examples of this landform in the world, notable for its size and central mountain mass.
[29]
Tweed Volcano - A biography of the Australian continent
Jun 22, 2009 · The Tweed Valley is the erosion caldera of the Mt Warning Shield Volcano. The Tweed Valley, the caldera, is more than 1000 m deep and 40 km wide.<|separator|>
[30]
The Wollumbin Caldera – It's Geological Formation and Flora
The caldera, with it's steep scarps rising 1150 m in altitude, forms an almost regular horseshoe about 15 km radius around Mount warning and acts as a giant ...
[31]
Booninybah | Fingal Head - Tweed Regional Museum
Fingal Head is a distinctive volcanic headland of rectangular basalt columns, formed as lava flowed toward the ocean 23 million years ago.
[32]
Nature, culture and history | Springbrook National Park
Feb 21, 2025 · The landscape of the Springbrook plateau is a remnant of the northern side of a once huge shield volcano that dominated the region about 23 ...
[33]
Nature, culture and history | Lamington National Park
Tamborine, Springbrook, Beechmont and Lamington are remnants of the Tweed shield volcano's northern flank. The old volcano's core remains at Mount Warning.Missing: Fingal Head