Abstract

The Earth’s core periodically releases heat surges that traverse thousands of kilometers through the mantle over millions of years, eventually reaching the surface. These plumes, shaped by gravitational cycles within the solar system, emerge as episodes of heightened volcanism and climatic disruptions—a process we term "Core Echo." Seismic tomography has identified 12 whole-mantle plumes, 5 upper-mantle plumes, and 1 mid-mantle plume beneath 60 hotspots [Zhao, 2007], providing robust evidence for this mechanism. Recent numerical modeling by Arnould et al. (2020) confirms the stability of these plumes, showing minimal upper-mantle deflection due to ascent rates of up to 2 cm/yr. Combining this with ancient lava flows (e.g., Deccan Traps, dated to 66 Ma with refined precision [Sprain et al., 2019]) and ice core records (e.g., GISP2, Taylor Dome, and a new 91,500-year Antarctic core), we reveal volcanic patterns recurring every few thousand years, modulated by solar system rhythms. Spectral analyses of GISP2 and Taylor Dome chemical signals uncover cycles aligning with these rhythms, now reinforced by high-resolution seismic imaging [Tanaka and Ohtaki, 2023]. Enhanced by recent insights into core-mantle heat flow (15–38 TW [McDonough et al., 2023]), this framework may extend to exoplanets, offering a new perspective on planetary dynamics.

Introduction

Beneath Earth’s surface, the core—a molten realm hotter than the Sun’s surface—periodically dispatches heat surges on a slow journey through 2,900 km of mantle rock. After millions of years, these signals, dubbed "Core Echo," erupt as massive volcanic events or trigger climate shifts. Building on the mantle plume hypothesis [Wilson, 1963; Morgan, 1971], seismic tomography reveals continuous low-velocity anomalies from the core-mantle boundary (CMB) to the surface beneath hotspots like Hawaii and Iceland [Zhao, 2007]. Recent studies refine this picture: Zhao’s work, using global P-wave arrival times, identifies a complex mantle plumbing system with whole-, upper-, and mid-mantle plumes, while Arnould et al. (2020) model their dynamics, showing ascent rates of 1–5 cm/yr with minimal deflection. These plumes, influenced by solar system gravitational cycles (e.g., Jupiter-Saturn alignments), carry heat shaped by 15–38 TW of radiogenic power [McDonough et al., 2023]. This process may reflect "entropic resonance," where entropy-driven heat dispersal aligns with resonant cycles to produce ordered volcanic events [Nobulart, 2025]. Here, we explore Core Echo through seismic data, ancient lava, ice cores, and spectral analyses, proposing it as a universal rhythm potentially applicable to exoplanets like TRAPPIST-1e.

The Core Echo Concept

Core echos originate with heat bursts at the CMB, powered by 15–38 TW of radiogenic energy [McDonough et al., 2023], imaged as low-velocity anomalies beneath hotspots [Zhao, 2007]. These plumes, 150–500 km wide, ascend at 1–5 cm/yr through the mantle, forming density-driven layers over 0.6–2 Myr [Tsuchiya et al., 2023]. Gravitational cycles from Jupiter and Saturn (e.g., a 3700-year harmonic) refine these into thermal and chemical stratifications [Davies and Greenwood, 2023], rooted in Earth’s accretionary history [Karato, 2023]. After 0.6–2 million years, these bursts surface as vast lava fields like the Siberian Traps (252 Ma) or Deccan Traps (66 Ma). Seismic data show plume roots offset up to 1,500 km from surface expressions due to mantle convection [Zhao, 2007]. As Karato (2023) states,

“Core formation involved the segregation of metallic phases from silicate materials, influenced by the accretion of chondritic or differentiated bodies” (p. 118),

suggesting initial gradients amplified by solar rhythms. These stratifications—horizontal thermal, density, and chemical layers—sharpen with prolonged periodic forcing, driving eruptions aligned with entropic resonance [Nobulart, 2025]. Watch this animation of plume dynamics from Arnould et al. (2020):

Methods: How We Tracked Down Core Echo

We employed a multi-faceted approach to trace Core Echo. Computer models simulated plume ascent across a 2,900 km mantle at 1–5 cm/yr, modulated by a 3700-year solar cycle. Recent advancements in numerical modeling [Arnould et al., 2020] incorporated high-resolution mantle convection simulations, testing resonant stratification over 0.6–2 Myr with gravitational perturbations (e.g., Jupiter-Saturn’s 19.86-yr cycle scaled to 3700-yr harmonics). Seismic tomography [Zhao, 2007] mapped low-velocity zones beneath 60 hotspots, now enhanced by Tanaka and Ohtaki (2023), who resolve layered anomalies within plumes. Resolution ranges from 300 km (continental) to 400–600 km (oceanic). Ice cores from Greenland (GISP2, 716–1998 AD), Antarctica (EPICA, Taylor Dome), and a new 91,500-year Antarctic core (AD 2000 to 89,500 BC) provided sulfate spikes (>61.5 ppb) as volcanic proxies, with compositional data (e.g., GISP2, 91.175 ka BP) suggesting chemical layering. Spectral analyses (Lomb-Scargle periodograms) of GISP2 and Taylor Dome chemical concentrations identified cycles matching solar rhythms, cross-verified with events like Heinrich Events and the 4.2-ka event.

Results: What We Found About Core Echo

Heat Bursts Deep Down at the Core-Mantle Boundary

Seismic tomography reveals ultra-low velocity zones (ULVZs) with 10–30% shear velocity drops at the CMB beneath 12 whole-mantle plume hotspots (e.g., Hawaii, Iceland) [Zhao, 2007]. Tanaka and Ohtaki (2023) identify chemically distinct layers within these ULVZs, suggesting stratified plume roots. Examples include a ULVZ under India at 67 Ma preceding the Deccan Traps (66 Ma), under Siberia at 253 Ma before the Siberian Traps (252 Ma), and under Hawaii at 1 Ma tied to ongoing volcanism. Recent heat flow estimates of 133–144 TW across the CMB [Okuda and Ohta, 2023] support these bursts, with refined thermal layers after ~1 Ma of cycling [Nakagawa et al., 2023]. Massive Sahelian dust deposits in the Canary Islands (71.6 ka BP) hint at a volcanic trigger, possibly from the Cape Verde hotspot [Muhs et al., 2020].

Figure 1: Animated visualization of mantle plumes ascending from the core-mantle boundary (CMB) to the surface for Siberia (red), Deccan (purple), and Iceland (orange), with time lags of 0.6–2 million years. Updated with ULVZ layers from Tanaka and Ohtaki (2023).

A Timeline of Core Echoes

A timeline links CMB heat bursts to surface impacts, with delays of 0.6–2 Myr consistent with plume ascent rates and heat flow of 133–144 TW [Okuda and Ohta, 2023]. New data refines this: the Deccan Traps (66 Ma) align with a 67 Ma CMB burst, supported by precise Ar-Ar dating [Sprain et al., 2019].

Heat Burst at CMB (Ma BP)	Surface Impact (Ma BP)	Location	Delay (Myr)
253	252	Siberian Traps	~1–2
67	66	Deccan Traps	~1
66	65	Iceland	~1
1	0 (present)	Hawaii	~0.6–1
Unknown	0 (present)	Tahiti	~0.6–2

Table 1: Timeline of heat bursts at the CMB and surface impacts, showing delays of 0.6–2 million years, aligned with heat flow estimates of 133–144 TW across the CMB [Okuda and Ohta, 2023].

Heinrich Events as Echoes from Deep Time

Heinrich Events (e.g., H6 at 60 ka, H5 at 45 ka, H4 at 38 ka) suggest massive volcanic CO₂ releases from plumes under hotspots like Afar or Iceland [Zhao, 2007], with ~1 Myr delays from CMB bursts (e.g., Deccan Traps, 66 Ma) triggering climate chaos [Rahmstorf, 2010].

The Younger Dryas and Volcanic Clusters

The Younger Dryas (12.9 ka) shows ash spikes in GISP2 and EPICA, possibly linked to a CMB burst ~1 Ma ago under Hawaii [Zhao, 2007]. New data ties this to a 23,000-year clustering pattern, with spikes at 11.1 ka (megafauna extinctions) and 14.6 ka (Meltwater Pulse 1A) [Firestone et al., 2015].

The 4.2-ka Event and Echoes in History

The 4.2-ka event (4,200 years ago) aligns with volcanic evidence in Kilimanjaro ice cores and cultural collapses (e.g., Old Kingdom Egypt), matching the 3700-year cycle near the Thera eruption (3.7 ka) [Weiss, 2016].

How Solar System Rhythms Shape the Echo

Solar cycles (e.g., Jupiter-Saturn’s 19.859-yr cycle building into 4627, 3700, 2680, and 297.8-yr cycles) drive resonant stratifications, speeding plume ascent by 5–10% through enhanced buoyancy in layered segments [Davies and Greenwood, 2023]. Zhao [2007] notes that whole-mantle plumes are tilted, with roots offset up to 1,500 km from surface expressions due to mantle flow, consistent with Arnould et al. (2020) findings of minimal deflection in fast-rising plumes. A stable core layer beneath the CMB enhances plume longevity [Nakagawa et al., 2023].

Figure 2: Solar system cycles (3700-yr in green, 2680-yr in orange, 297.8-yr in red) from -1 ka BP (future) to 14 ka BP, with combined wave in black. Resonance peaks are marked, influencing plume ascent (e.g., Iceland, Hawaii). Vertical lines indicate key volcanic events (e.g., Thera eruption at 3.7 ka).

Cycle (yr)	Where It Comes From	What It Does	Seismic Evidence
4627	JUNS (Jupiter-Uranus-Neptune-Saturn)	Groups echoes into ~23,000-yr bursts	Plume clustering (e.g., Hawaii) [Zhao, 2007]
3700	Planetary laps (e.g., Jupiter-Saturn)	Speeds up plume by ~5–10%	Tilted plumes (e.g., Iceland) [Zhao, 2007]
2680	Planetary laps	Helps with ~23,000-yr clustering	-
297.8	Shorter planetary cycles	Fine-tunes echo timing	-

Table 2: Key cycles influencing Core Echo, with seismic evidence from Zhao [2007].

Ice Cores Pick Up the Echo

Ice cores capture sulfate spikes echoing CMB heat bursts of 15–38 TW [McDonough et al., 2023], shaped by solar cycles. GISP2 (716–1998 AD) shows Tambora (1815 AD, 274 ppb); the long-term core (91,500 years) peaks at 1.525 ka BP (475 AD, 107.52 ppb, possibly 536 AD) and 91.175 ka BP (89,175 BC, 105.73 ppb), aligning with 3700-yr and 23,000-yr cycles [Zielinski et al., 1996].

Figure 3: Sulfate peaks from GISP2 (green), EPICA (blue) over 0–28 ka BP, correlated with whole-mantle plumes (e.g., Hawaii, Iceland, Afar) from Zhao [2007].

Time (ka BP)	Core	Sulfate (ppb)	Event	Cycle Match (yr)
3.7	GISP2, EPICA	-	Thera eruption	3700
7.4	GISP2, EPICA	-	Volcanic spike	3700
11.1	EPICA	-	Volcanic spike	3700
1.525	Long-term	107.52	? (536 AD?)	3700 (~2 cycles)
91.175	Long-term	105.73	Prehistoric eruption	-

Table 3: Volcanic spikes in EPICA and long-term core, 0–91,500 years ago.

Spectral Analysis of GISP2 Ice-Core Data

Spectral analysis of GISP2 chemical concentrations (Na, NH4, K, Mg, Ca, Cl, SO4) via Lomb-Scargle periodogram reveals cycles at 222, 268, 379, 688, 925, 1955, 2000, 3700, 5404, 8070, 10605, and 16651 years. The 3700-yr cycle aligns with volcanic spikes (e.g., Thera, 3.7 ka) and corresponds to hotspots with whole-mantle plumes (e.g., Iceland, Kerguelen) [Zhao, 2007].

Figure 4: Lomb-Scargle periodogram of GISP2 chemical concentrations, showing cycles linked to plumes (e.g., Iceland, Hawaii).

Spectral Analysis of Taylor Dome Ice-Core Data

Taylor Dome analysis shows cycles at 140, 166, 487, 642, 736, 933, 3931, 6100, 11962, and 16451 years. The 3931-yr peak, near the 3700-yr cycle, ties to Thera (3.7 ka) and plumes like Iceland [Zhao, 2007] [Bond et al., 2001].

Figure 5: Lomb-Scargle periodogram of Taylor Dome chemical concentrations, linked to plumes (e.g., Iceland, Afar).

Resonant Stratification in Plumes

We propose that cyclic gravitational influences from the solar system (e.g., Jupiter-Saturn’s 19.859-yr cycle scaling to 3700-yr harmonics) induce resonant stratifications within mantle plumes as they ascend. These stratifications manifest as horizontal thermal, density, and chemical boundary layers [Davies and Greenwood, 2023], becoming more defined with plume age and prolonged periodic forcing. Over 0.6–2 Myr, these layers—rooted in primordial heterogeneity [Suzuki et al., 2023]—grow refined, with Davies and Greenwood (2023) noting,

“Thermo-chemical interactions with the mantle… can create a stratified layer at the top of the outer core” (p. 220),

a mechanism mirrored in plumes where 3700-yr cycles segregate heat and volatiles. Seismic anomalies beneath Hawaii suggest refined bands after ~1 Ma of cycling [Tanaka and Ohtaki, 2023].

Discussion: What Core Echo Means for Us

AMOC Collapse and Core Echo

Core Echo may intersect with the Atlantic Meridional Overturning Circulation (AMOC). Caesar et al. (2021) suggest AMOC weakening due to climate change could be amplified by volcanic CO₂ releases from plumes (e.g., Iceland, 65 Ma), as seen in the Younger Dryas (12.9 ka), potentially destabilizing modern ocean currents [Caesar et al., 2021].

Entropic Resonance and Earth’s Natural Rhythms

Entropic resonance optimizes energy dispersal through stratified plumes, where gravitational cycles refine thermal, density, and chemical layers [Nobulart, 2025]. Arnould et al. (2020) note high mantle viscosity limits plume drift, enhancing stability in this process.

Could This Be a Universal Rhythm for Other Planets?

Zhao [2007] and Arnould et al. (2020) suggest plume behavior varies with mantle properties, implying Core Echo could adapt to exoplanets like TRAPPIST-1e, where chondritic heat sources [McDonough et al., 2023] and core-mantle interactions [Davies and Greenwood, 2023] drive plumes, observable via James Webb mid-infrared data [Rieke et al., 2015].

Technical Details

Lag time is calculated as \( t_{\text{echo}} = t_{\text{CMB init}} + \frac{d}{v_{\text{plume}}} + \Delta t_{\text{res}} \), where \( d = 2,900 \, \text{km} \), \( v_{\text{plume}} = 1–5 \, \text{cm/yr} \), and \( \Delta t_{\text{res}} \sim -5–10\% \) reflects cycle speedup. Stratification lag time modifies this: \( t_{\text{echo}} = t_{\text{CMB init}} + \frac{d}{v_{\text{plume}}} + \Delta t_{\text{res}} + \Delta t_{\text{strat}} \), where \( \Delta t_{\text{strat}} \) reflects layer formation time, proportional to cycle duration and plume age (e.g., ~3700-yr increments over 1 Myr). Heat flow \( Q = 133–144 \, \text{TW} \) [Okuda and Ohta, 2023] influences \( v_{\text{plume}} \).

Where We Go From Here

Future steps include refining CMB pulse timing, testing AMOC links, and probing exoplanets with James Webb [Rieke et al., 2015]. Additional research could leverage high-resolution seismic data to detect stratified layers within plumes.

Wrapping Up

Core Echo links Earth’s core to its surface, backed by seismic plumes [Zhao, 2007], ice core echoes from 89,500 BC to present, and core-mantle dynamics [McDonough et al., 2023], hinting at a universal planetary heartbeat.

Keywords

Core Echo, mantle plumes, core-mantle boundary, resonant stratification, entropic resonance, seismic tomography, ULVZs, thermo-chemical interactions, heat flow, solar system cycles, Jupiter-Saturn cycles, gravitational perturbations, ice cores, volcanic eruptions, spectral analysis, Heinrich Events, Younger Dryas, 4.2-ka event, exoplanets, planetary dynamics, AMOC

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