Vox Geophysics' Expert Modelling Confirms High-Priority REE Target at Colosseum's 2200N
Dateline Resources (OTCQB:DTREF) announced that a second ModEM 3D magneto-telluric (MT) inversion model has confirmed a high-priority Rare Earth Elements (REE) drill target at its Colosseum Gold-REE Project in California. The independent validation, conducted by Dr. Kate Selway of Vox Geophysics, corroborates the previous RLM-3D model findings from August.
The models identified a resistive anomaly on line 2200N, extending from approximately 1,000m depth to the surface, coinciding with fenite dykes. This geological signature suggests potential carbonatite-hosted REE mineralization. The company plans to commence drill testing of this target, along with several gold targets, in the December quarter 2025.
Dateline Resources (OTCQB:DTREF) ha annunciato che un secondo modello di inversione ModEM 3D MT ha confermato un target di trivellazione ad alta priorità di elementi di terre rare (REE) nel suo Colosseum Gold-REE Project in California. La validazione indipendente, condotta dalla Dott.ssa Kate Selway di Vox Geophysics, corroborà i risultati del precedente modello RLM-3D di agosto.
I modelli hanno identificato una anomalìa resistiva sulla linea 2200N, che si estende da circa 1.000 m di profondità fino alla superficie, coincidendo con dossi fenitici. Questo profilo geologico suggerisce una possibile mineralizzazione REE ospitata in carbonatite. L'azienda intende avviare le trivellazioni su questo target, insieme a diversi obiettivi legati all'oro, nel quartone dicembre 2025.
Dateline Resources (OTCQB:DTREF) anunció que un segundo modelo de inversión ModEM 3D MT ha confirmado un objetivo de perforación de alta prioridad de Elementos de Tierra Rara (REE) en su Proyecto Colosseum Gold-REE en California. La validación independiente, realizada por la Dra. Kate Selway de Vox Geophysics, corrobora los hallazgos del modelo RLM-3D de agosto.
Los modelos identificaron una anomalía resistiva en la línea 2200N, que se extiende desde aproximadamente 1,000 m de profundidad hasta la superficie, coincidiendo con dykes feníticos. Esta firma geológica sugiere una posible mineralización REE alojada en carbonatita. La empresa planea iniciar pruebas de perforación de este objetivo, junto con varios objetivos de oro, en el cuarto trimestre de 2025.
Dateline Resources (OTCQB:DTREF)는 캘리포니아의 Colosseum Gold-REE Project에서 고우선 순위 희토류 원소(REE) 시추 타깃을 확인했다는 두 번째 ModEM 3D MT 역산 모델이 확인했다고 발표했습니다. Vox Geophysics의 Kate Selway 박사가 수행한 독립 검증은 8월의 기존 RLM-3D 모델 결과를 입증합니다.
모델은 2200N 선의 저항 이상을 식별했고, 약 1,000m 깊이에서 표면까지 확장되며 페닛 다익과 일치합니다. 이 지질 기 signature은 탄산염암 호스트 REE 광상이 있을 가능성을 시사합니다. 회사는 이 목표뿐 아니라 여러 금(Target) 목표에 대해 2025년 12분기에 시추 테스트를 시작할 계획입니다.
Dateline Resources (OTCQB:DTREF) a annoncé qu’un second modèle d’inversion ModEM 3D MT a confirmé une cible de forage prioritaire pour les éléments des terres rares (REE) sur son Projet Colosseum Gold-REE en Californie. La validation indépendante, réalisée par la docteure Kate Selway de Vox Geophysics, confirme les résultats du modèle RLM-3D précédemment publié en août.
Les modèles ont identifié une anomalie résistive sur la ligne 2200N, s’étendant d’environ 1 000 m de profondeur jusqu’à la surface, en coïncidence avec des dykes fenitiques. Cette signature géologique suggère une minéralisation REE potentielle associée à une carbonatite. L’entreprise prévoit de commencer les tests de forage sur cette cible, ainsi que sur plusieurs cibles aurifères, au quatrième trimestre 2025.
Dateline Resources (OTCQB:DTREF) gab bekannt, dass ein zweites ModEM-3D-MT-Inversionsmodell eine vorrangige Zielstelle für Seltene Erden (REE) beim Colosseum Gold-REE-Projekt in Kalifornien bestätigt hat. Die unabhängige Validierung durch Dr. Kate Selway von Vox Geophysics bestätigt die zuvor im August erhaltenen RLM-3D-Modellbefunde.
Die Modelle identifizierten eine resisitive Anomalie auf der Linie 2200N, die sich von ca. 1.000 m Tiefe bis zur Oberfläche erstreckt und mit Fenit-Dykes übereinstimmt. Dieses geologische Signaturbild deutet auf eine potenzielle karbonatitisch-haltige REE-Mineralisierung hin. Das Unternehmen plant, diese Zielsetzung sowie mehrere Goldziele im vierten Quartal 2025 zu bohren.
أعلنت Dateline Resources (OTCQB:DTREF) أن نموذج تحويل ModEM 3D MT ثانٍ قد أكد هدف حفر عالي الأولوية لعناصر الأرض النادرة (REE) في مشروع Colosseum Gold-REE في كاليفورنيا. وتدعم التحقق المستقل الذي أجرته الدكتورة كيت سلوِ من Vox Geophysics نتائج نموذج RLM-3D السابق من أغسطس.
حددت النماذج شذوذ مقاوم على الخط 2200N يمتد من عمق يقارب 1000 م حتى السطح، ويتزامن مع عروق fenite. تشير هذه العلامة الجيولوجية إلى إمكان وجود معدنية REE مستضافة في carbonatite. تخطط الشركة لبدء اختبارات الحفر لهذا الهدف، مع عدة أهداف ذهبية، في الربع الرابع من 2025.
Dateline Resources (OTCQB:DTREF) 宣布，另一组 ModEM 3D MT 反演模型已证实其在 加州Colosseum Gold-REE 项目的高优先级稀土元素（REE）钻探目标。由 Vox Geophysics 的 Kate Selway 博士进行的独立验证，证实了8月时的 RLM-3D 模型结果。
模型识别到一处 2200N 线上的电性反常，深度约为 1000 m 至地表，且与 Fenite 岩脉一致。这一地质信号提示可能存在以碳酸岩为宿主的REE矿化。公司计划在 2025 年第四季度开始对该目标进行钻探测试，以及若干金矿目标的钻探。
- Independent validation by two expert groups confirms high-priority REE target
- Target shows similarities to nearby Mountain Pass carbonatite REE deposit
- Diamond drilling program already underway as part of Bankable Feasibility Study
- Additional drilling rigs being mobilized to accelerate exploration
- Target area has no historical drilling data
- Depth of potential mineralization extends to approximately 1,000m
Strengthening Domestic Critical Mineral Supply
SAN BERNARDINO, CALIFORNIA / ACCESS Newswire / September 24, 2025 / Dateline Resources Limited (ASX:DTR)(OTCQB:DTREF)(FSE:YE1) is pleased to announce that second ModEM 3D magneto-telluric (MT) inversion result has also confirmed the high-priority REE drill target on line 2200N at its
Highlights
ModEM Model Review: A second 3D MT inversion model has confirmed the high priority 2200N REE target, located just north of the historical gold open pits.
Model Consistency: The RLM-3D and new ModEM inversions produced resistivity models with very similar features, providing strong cross-validation of the target.
Deep, Coincident Anomaly: In both models, a resistive region extends to at least ~1,000 m depth below the surface, spatially coincident with outcropping REE bearing fenite dykes (consistent with an REE bearing carbonatite source).
Upcoming Drilling:Majors Drilling will mobilise additional rigs in coming weeks to expedite testing of this high-priority REE drill target.
Parallel Validation Underway for Gold Targets: A second-party review is in progress to validate the six new gold breccia pipe targets identified in August 2025, strengthening confidence ahead of drill testing.
In both models, a prominent resistive anomaly is observed on line 2200N, extending from ~1,000 m depth up to surface and coincident with surface fenite dykes. Notably, this resistive body's alignment with fenite (an alteration typically haloing carbonatite intrusions) is consistent with a carbonatite source, indicating carbonatite-hosted potential for REE mineralisation at depth
Dateline's Managing Director, Stephen Baghdadi, commented:
"This new modelling, conducted by two highly skilled groups, using different analysis software and inversion modelling methods have both confirmed the exciting 2200N rare earth target, we look forward to drill testing our new REE and gold targets and adding further value for shareholders."
Figure 1: 3D MT resistivity cross-section (Line 2200N) modelled using Viridien's RLM-3D inversion. The prominent high-resistivity anomaly (blue zones) extends from ~1,000 m depth to surface beneath the area of known fenite dykes. This deep resistive body is interpreted as a potential carbonatite intrusion associated with REE mineralisation. (Vertical axis in metres; horizontal axis in metres along line.)
Figure 2: 3D MT resistivity cross-section (Line 2200N) from the independent ModEM inversion by Vox Geophysics. The ModEM result reveals an almost identical resistive anomaly (Blue) in the same location and depth range as the RLM-3D model. This independent replication strongly validates the target's robustness. The consistency between the two models underscores this high-priority anomaly's carbonatite-hosted potential as an REE system.
Magneto-Telluric Inversion Modelling
The MT survey data (167 stations on 14 lines) were reprocessed by Vox Geophysics using the ModEM inversion algorithm to generate a fresh 3D resistivity model for the Colosseum Project.
Figure 3: Plan view of Colosseum claim boundary showing MT survey lines and REE bearing fenite outcrops in black diamonds.
Dr. Selway, a globally recognized expert in magneto-telluric data analysis with over 20 years of experience, holds a PhD in MT methodologies and has conducted fieldwork across diverse regions, including Antarctica, Greenland, East Africa, Australia, and the United States. Her extensive academic background includes roles at prestigious institutions such as the University of Adelaide, Yale University, Lamont-Doherty Earth Observatory, and the University of Oslo, complemented by contributions to high-profile geophysical publications.
Dr Kate Selway, Managing Director of Vox Geophysics, noted: "The two independent RLM-3D and ModEM approaches, with independent data analysis and different inversion codes, have produced resistivity models with very similar features. This cross-validation between the two independent approaches provides confidence that features consistently imaged in both models are robust and reliable."
This independent model closely mirrors the original RLM-3D model, confirming all major resistive and conductive features. Crucially, the east-west Line 2200N anomaly - previously highlighted as a zone of REE potential - appears virtually identical in both models. In each case, a broad high-resistivity zone (hundreds of metres across) rises from at least ~1 km depth to the near-surface, directly beneath outcrops of fenite dykes. The duplication of this feature by two independent inversion codes greatly reinforces confidence in its geologic significance. The spatial coincidence of a deep-seated resistive body with surface fenite alteration is a signature characteristic of carbonatite-centred REE systems, suggesting that the 2200N anomaly may represent a carbonatite intrusive source for REE mineralisation. This interpretation aligns with other geophysical evidence at Colosseum, where the 2200N target area also shows a gravity high and magnetic low pattern analogous to the nearby Mountain Pass carbonatite REE deposit (~10 km south).
Next Steps: Drilling and Exploration Strategy
Drill Testing: Dateline plans to commence drill testing of the new rare earth target on line 2200N (along with several new gold targets) in the upcoming December quarter. Diamond drilling is already underway at Colosseum, focused on infill and extensional holes in the existing gold mineral resource as part of a Bankable Feasibility Study (BFS). Drill rigs are being mobilised to site through September-October to accelerate the exploration program and fast-track the testing of newly defined targets. The 2200N anomaly, now supported by two independent 3D models and surface geological indicators, is regarded as a high-priority REE drill target and will be a key focus of the upcoming campaign.
Importantly, the area of the 2200N anomaly has seen no historical drilling. Past exploration at Colosseum was largely gold-focused and concentrated around the known breccia pipe gold outcrops, leaving the REE potential of the broader system underexplored. The newly defined 2200N target therefore represents a potential fresh discovery.
Broader Exploration Strategy: The validation of this REE target is in keeping with Dateline's dual-track strategy at Colosseum of advancing the known gold deposit toward development while unlocking new value in the project's rare earth and additional potential gold bearing breccia pipe targets. The Company's rigorous approach to data collection, now bolstered by the latest 3D MT results, is designed to de-risk drill targeting and maximize the chance of discovery. Dateline's technical team will incorporate the ModEM model insights into final drill planning for the REE targets.
MT Gold Target Review: In addition to the REE inversion validation, Dateline has initiated a secondary review of the gold-focused MT model. This review aims to independently validate the six high-priority breccia pipe targets announced in August 2025. Results from this validation will be disclosed to the market when completed and integrated into the final drill targeting model as Dateline prepares to test both gold and REE targets in the current campaign.
This press release has been authorized for release by the Board of Dateline Resources Limited.
For more information, please contact:
Stephen Baghdadi
Managing Director
+61 2 9375 2353
Andrew Rowell
Corporate & Investor Relations Manager
+61 400 466 226
a.rowell@dtraux.com
www.datelineresources.com.au
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About Dateline Resources Limited
Dateline Resources Limited (ASX:DTR)(OTCQB:DTREF)(FSE:YE1.F) is an Australian company focused on mining and exploration in North America. The Company owns
The Colosseum Gold Mine is located in the Walker Lane Trend in East San Bernardino County, California. On 6 June 2024, the Company announced to the ASX that the Colosseum Gold mine has a JORC-2012 compliant Mineral Resource estimate of 27.1Mt @ 1.26g/t Au for 1.1Moz. Of the total Mineral Resource, 455koz @ 1.47/t Au (
On 23 May 2025, Dateline announced that updated economics for the Colosseum Gold Project generated an NPV6.5 of US
The Colosseum is located less than 10km north of the Mountain Pass Rare Earth mine. Planning has commenced on drill testing the REE potential at Colosseum.
Dateline has also acquired the high-grade Argos Strontium Project, also located in San Bernadino County, California. Argos is reportedly the largest strontium deposit in the U.S. with previous celestite production grading
Forward-Looking Statements
This announcement may contain "forward-looking statements" concerning Dateline Resources that are subject to risks and uncertainties. Generally, the words "will", "may", "should", "continue", "believes", "expects", "intends", "anticipates" or similar expressions identify forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from those expressed in the forward-looking statements. Many of these risks and uncertainties relate to factors that are beyond Dateline Resources' ability to control or estimate precisely, such as future market conditions, changes in regulatory environment and the behavior of other market participants. Dateline Resources cannot give any assurance that such forward-looking statements will prove to have been correct. The reader is cautioned not to place undue reliance on these forward-looking statements. Dateline Resources assumes no obligation and does not undertake any obligation to update or revise publicly any of the forward-looking statements set out herein, whether as a result of new information, future events or otherwise, except to the extent legally required.
Competent Person Statement
Sample preparation and any exploration information in this announcement is based upon work reviewed by Mr Greg Hall who is a Chartered Professional of the Australasian Institute of Mining and Metallurgy (CP-IMM). Mr Hall has sufficient experience that is relevant to the style of mineralization and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the "Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves" (JORC Code). Mr Hall is a Non-Executive Director of Dateline Resources Limited and consents to the inclusion in the report of the matters based on this information in the form and context in which it appears.
Company Confirmations
The Company confirms it is not aware of any new information or data that materially affects the information included in the announcements dated 23 October 2024 with regard to the Colosseum MRE and 23 May 2025 with regard to Colosseum Project Economics. Similarly, the Company confirms that all material assumptions and technical parameters underpinning the estimates and the forecast financial information referred to in those previous announcements continue to apply and have not materially changed.
SOURCE: Dateline Resources Limited
View the original press release on ACCESS Newswire
FAQ
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