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The Wandel Sea Basin in North Greenland was part of the epicontinental Boreal Sea in Triassic time. The basin formed the western margin of the northernmost Atlantic elongated sea connecting southwards with basins along the conjugate Greenland—Norwegian margins. A multidisciplinary dataset including sedimentology, biostratigraphy, organic geochemistry and sedimentary provenance, allow to document its basin evolution. The Wandel Sea Basin was transgressed in the Dienerian with marine deposition prevailing until the Norian. Sediments were mainly sourced from the Greenlandic Caledonian basement and deposited on a 100 km wide shallow marine shelf during the Early Triassic. In Middle Triassic, oil-prone mudstones formed in oxygen-depleted deep shelf settings, including eastern Wandel Sea Basin. Detrital zircon U–Pb ages show that by Carnian times, the >1000 km wide, Uralian-sourced, deltaic shelf had prograded westward across the Barents Sea reaching the eastern north Greenland and de facto nearly closed the northernmost Atlantic Sea.

Located at the junction between the Beibuwan Basin and the Song Hong Basin in the Gulf of Tonkin, the Bach Long Vi (BLV) island offers a rare window into the Cenozoic geology of Indochina and surrounding region. The island exposes 5 km-long continuous outcrop of weakly to moderately dipping Oligocene deep-lake deposits along the coastline. Using integrated UAV imaging and modern field methods, we characterized the deformation on the island at unprecedented level of details, and then related these features to regional tectonic events. BLV's mudstone-rich succession was intruded by pervasive sand injectites which consist of three main types: linear dikes, irregular dikes, and irregular sandstone bodies. Linear dikes and irregular dikes are found throughout most of the island. Linear dikes are steeply dipping, trend dominantly ENE, and tends to be thicker close to the top of the island stratigraphy. Irregular dikes have contorted shapes both in plan view and cross-section, and often connect adjacent linear dike segments. Irregular sandstone bodies are located toward the highest part of the island stratigraphy, and are characterized by depositional sands modified by sand injection processes. Most of the sand injectites on BLV constitute an interconnected complex that formed at the same time, probably in the late Oligocene during syn-rift. Sand injectites are later cross-cut by NW-SE left-lateral and its conjugate NE-SW right-lateral strike-slip faulting. The inferred ENE-trending maximum principal stress and NNW-trending minimum principal stress of this deformation is compatible with the regional end-Oligocene inversion as indicated by seismic data.

The little explored Cambodian and Vietnamese Phuquoc–Kampot Som Basin is a Late Jurassic to Early Cretaceous foreland basin developed in response to the build-up of a palaeo-Pacific magmatic arc. A combination of seismic data, well data and outcrop geology complemented by fission track and U/Pb analysis is used to unravel the basin history. This reveals a hitherto unknown earliest Palaeogene basin inversion associated with the Luconian suturing to SE Asia and the shutdown of palaeo-Pacific subduction underneath SE Asia. The Phuquoc–Kampot Som Basin and the Khorat Basin in Thailand constitute the erosional remnants of a larger basin that covered large parts of SE Asia in Late Mesozoic time, and subsequently became segregated during earliest Palaeogene inversion and erosion. Inversion was focused along the several hundred kilometres long Kampot and Khmer–Chanthaburi fold belts that confine the Phuquoc–Kampot Som Basin and merge with the Mae Ping and the Three Pagodas fault zones. These connections, together with local NW–SE-trending sinistral transpressional faults offshore, indicate a link between initial SE Asian left-lateral strike-slip faulting and the Luconian suturing. The separation between the once unbroken Khmer–Chanthaburi Fold Belt and the Phetchabun Fold Belt in Thailand suggests a 50–100 km Cenozoic left-lateral offset across the Mae Ping Fault Zone.