In 2007, the Antarctic Geological Drilling\ud Program (ANDRILL) drilled 1138.54 m of\ud strata ~10 km off the East Antarctic coast,\ud includ ing an expanded early to middle Miocene\ud succession not previously recovered\ud from the Antarctic continental shelf. Here,\ud we pre sent a facies model, distribution, and\ud paleoclimatic interpretation for the AND-2A\ud drill hole, which enable us, for the fi rst time,\ud to reconstruct periods of early and middle\ud Miocene glacial advance and retreat and\ud paleo environmental changes at an ice-proximal\ud site. Three types of facies associations\ud can be recognized that imply signifi cantly\ud different paleoclimatic interpretations. (1) A\ud diamictite-dominated facies association represents\ud glacially dominated depositional environments,\ud including subglacial environments,\ud with only brief intervals where ice-free coasts\ud existed, and periods when the ice sheet was\ud periodically larger than the modern ice sheet.\ud (2) A stratifi ed diamictite and mudstone facies\ud association includes facies characteristic of\ud open-marine to iceberg-infl uenced depositional\ud environments and is more consistent\ud with a very dynamic ice sheet, with a grounding\ud line south of the modern position. (3) A\ud mudstone-dominated facies association generally\ud lacks diamictites and was produced in a\ud glacially infl uenced hemipelagic depositional\ud environment. Based on the distribution of\ud these facies associations, we can conclude that\ud the Antarctic ice sheets were dynamic, with\ud grounding lines south of the modern location\ud at ca. 20.1–19.6 Ma and ca. 19.3–18.7 Ma and during the Miocene climatic optimum, ca.\ud 17.6–15.4 Ma, with ice-sheet and sea-ice minima\ud at ca. 16.5–16.3 Ma and ca. 15.7–15.6 Ma.\ud While glacial minima at ca. 20.1–19.6 Ma\ud and ca. 19.3–18.7 Ma were characterized by\ud temperate margins, an increased abundance\ud of gravelly facies and diatomaceous siltstone\ud and a lack of meltwater plume deposits suggest\ud a cooler and drier climate with polythermal\ud conditions for the Miocene climatic\ud optimum (ca. 17.6–15.4 Ma). Several periods\ud of major ice growth with a grounding line traversing\ud the drill site are recognized between\ud ca. 20.2 and 17.6 Ma, and after ca. 15.4 Ma,\ud with evidence of cold polar glaciers with ice\ud shelves. The AND-2A core provides proximal\ud evidence that during the middle Miocene climate\ud transition, an ice sheet larger than the\ud modern ice sheet was already present by ca.\ud 14.7 Ma, ~1 m.y. earlier than generally inferred\ud from deep-sea oxygen isotope records.\ud These fi ndings highlight the importance of\ud high-latitude ice-proximal records for the interpretation\ud of far-fi eld proxies across major\ud climate transitions

Eocene onset of subduction in the western Pacific was accompanied by a global reorganization of tectonic plates and a change in Pacific plate motion relative to hotspots during the period 52–43 Ma. We present seismic-reflection and rock sample data from the Tasman Sea that demonstrate that there was a period of widespread Eocene continental and oceanic compressional plate failure after 53–48 Ma that lasted until at least 37–34 Ma. We call this the Tectonic Event of the Cenozoic in the Tasman Area (TECTA). Its compressional nature is different from coeval tensile stresses and back-arc opening after 50 Ma in the Izu-Bonin-Mariana region. Our observations imply that spatial and temporal patterns of stress evolution during western Pacific Eocene subduction initiation were more varied than previously recognized. The evolving Eocene geometry of plates and boundaries played an important role in determining regional differences in stress state.

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The Teurian (paleocene) sequence at Te Kaukau Point, southeast Wairarapa, includes light green-grey, indurated, burrowed, slightly sandy calcilutite. These rocks are interbedded with laminated sandstone, mudstone, and siliceous limestone lithotypes, all of which are cut by intrusive sandstone. A variety of sedimentary structures, including burrows, indicate that the laminated sandstone was deposited conformably within the limestone sequence and is regarded as a turoidity current deposit, which later became overpressured to produce the intrusive sandstone.In terms of age, lithology, and stratigraphic position, the calcilutite at Te Kaukau is equivalent to the Amuri Limestone of the northeastern South Island.