Earth’s oldest tsunami deposit? Early Archaean high‐energy sediments in the ca 3.48 Ga Dresser Formation (Pilbara, Western Australia)

Abstract

Dynamic sedimentary processes are a key parameter for establishing the habitability of planetary surface environments on Earth and beyond and thus critical for reconstructing the early evolution of life on our planet. This paper presents a sedimentary section from the ca 3.48 Ga Dresser Formation (Pilbara Craton, Western Australia) that contains high-energy reworked sediments, possibly representing the oldest reported tsunami deposit on Earth to date. Field and petrographic evidence (e.g. up to 20 cm large imbricated clasts, hummocky bedding, Bouma-type graded sequences) indicate that the high-energy deposit represents a bi-directional succession of two debrite-turbidite couplets. This succession can best be explained by deposition related to passage and rebound of tsunami waves. Sedimentary processes were possibly influenced by highly dense silicarich seawater. The tsunami was probably triggered by local fault-induced seismic activity since the Dresser Formation was deposited in a volcanic caldera basin that experienced syndepositional extensional growth faulting. However, alternative triggers (meteorite impact, volcanic eruption) or a combination thereof cannot be excluded. The results of this work indicate a subaquatic habitat that was subject to tsunami-induced high-energy disturbance. Potentially, this was a common situation on the early Archaean Earth, which experienced frequent impacts of extraterrestrial bodies. This study thus adds to the scarce record of early Archaean high-energy deposits and stresses the relevance of high-energy depositional events for the early evolution of life on Earth.

Interpreting an Archaean paleoenvironment through 3D imagery of microbialites

“…An alternative source of high‐velocity currents could be from storms, and a prior study has found evidence of tsunami deposits in the Dresser Fm. (Runge et al., 2022). However, chips have been observed in multiple layers (Figure 2; see also Noffke et al., 2013), suggesting a repeated event, and the frequency and magnitude of storms during the Archaean is unknown.…”

“…An alternative source of highvelocity currents could be from storms, and a prior study has found evidence of tsunami deposits in the Dresser Fm. (Runge et al, 2022).…”

Reply on RC1

“…Interstitial carbonates were sampled from the ~3.49 Ga North Star Basalt (drill core 102 AIDP-1; 21°06'38"S, 119°06'4"E, French et al, 2015), the ~3.46 Ga Apex Basalt ("Schopf Locality" at Chinaman Creek; Schopf, 1993), the ~3.47 Ga Mount Ada Basalt and the ~3.35 Ga Euro Basalt (both near "Trendall Locality" at Shaw River;Hickmann et al, 2011), as well as from the Middle Basalt Member of ~3.48 Ga Dresser Formation (Dresser Barite Mine). Bedded sedimentary carbonates were sampled from the Dresser Formation at the "Tsunami Locality" (Runge et al 2022) near the Dresser Barite Mine, and the Euro Basalt at the east side of the Shaw River near the "Trendall Locality". Stromatolitic carbonates were collected from the Strelley Pool Formation at the western side of Shaw River.…”

“…The micritic carbonate is predominantly brownish and finely bedded. The association with pillow basalts indicates an interval of generally quiet-water sedimentation, although the succession might preserve the oldest record of a tsunami event on Earth(Runge et al 2022).…”

Were early Archean carbonate factories major carbon sinks on the juvenile Earth?

“…Interstitial carbonates were sampled from the ~3.49 Ga North Star Basalt (drill core 102 AIDP-1; 21°06'38"S, 119°06'4"E, French et al, 2015), the ~3.46 Ga Apex Basalt ("Schopf Locality" at Chinaman Creek; Schopf, 1993), the ~3.47 Ga Mount Ada Basalt and the ~3.35 Ga Euro Basalt (both near "Trendall Locality" at Shaw River;Hickmann et al, 2011), as well as from the Middle Basalt Member of ~3.48 Ga Dresser Formation (Dresser Barite Mine). Bedded sedimentary carbonates were sampled from the Dresser Formation at the "Tsunami Locality" (Runge et al 2022) near the Dresser Barite Mine, and the Euro Basalt at the east side of the Shaw River near the "Trendall Locality". Stromatolitic carbonates were collected from the Strelley Pool Formation at the western side of Shaw River.…”