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Ordovician conodont studies have revealed a depositional hiatus extending from the late Floian to early Darriwilian on the North China Platform. Recognition of this widespread gap entails revision of the original concept of the Huaiyuan Epeirogeny, with definition of two distinct regional tectonic events: Event 1, which initiated this hiatus, and a subsequent Event 2 that was responsible for terminating Early Palaeozoic sedimentation in the region from the late Katian. The timing of these two events partly coincides with widely recognized eustatic sea-level falls, and separates Ordovician sedimentation into two episodes that can be broadly correlated with eustatic sea-level rises. In combination with these sea-level changes, the Huaiyuan Epeirogeny played a decisive role in shaping and controlling Ordovician sedimentation and sequence stratigraphic architecture on the North China Platform. Lower Ordovician carbonates were deposited during an apparent regression (decreasing accommodation space), resulting from rapid sediment accumulation exceeding the overall rate of basement subsidence and eustatic sea-level rise. Sedimentation ceased in the middle to late Floian when basement uplift commenced in the south and extended northward to affect the entire platform. The diachronous top surface of the Lower Ordovician succession reflects extensive erosion that is most pronounced in the south and southwest parts of the platform where the disconformity surface cut down into Tremadocian (or even upper Cambrian) strata. Deposition of the younger sequence (Darriwilian to Katian) was the result of the interplay between rejuvenated basement subsidence and the late Middle Ordovician eustatic sea-level rise. Event 2, which was initially coupled with eustatic sea-level fall induced by the end-Ordovician glaciations, terminated Ordovician deposition in the region with the top of the Ordovician marked by an unconformity, representing a hiatus of some 122 Ma extending from latest Ordovician to latest Mississippian.

The Early Paleozoic featured nine intervals of strong expansion of an upper slope, dysoxic/anoxic (d/a) water mass with eustatic rise or epeirogenic transgression. Strong expansion of this d/a water mass led to deposition of time-specific, macroscale alternations of dark grey-black mudstone within oxic, green to red mudstone on the middle–lower slope. This d/a facies even onlapped warm- (carbonate) and cool-water (siliciclastic) shelves. As in the Mesozoic, d/a muds were deposited in shallow water, perhaps tens of metres deep, with sea-level rise. These nine d/a macroscale alternations correspond to intervals of “global hyperwarming”—times of very intense greenhouse conditions that resulted from a feedback initiated by higher insolation and heat storage as shallow seas onlap tropical palaeocontinents. Warm epeiric seas heated the ocean, and thermal expansion accelerated eustatic rise. Ever more extensive epeiric seas heightened oceanic and global temperature as heat storage capacity increased. Deep ocean circulation intensity fell below that of a greenhouse interval and lead to d/a deposition low on the slope and on the platforms to provide the signature of global hyperwarming. Global hyperwarming differs from a hothouse interval as it does not require CO 2 input from large igneous provinces to produce high temperatures and never shows deep-sea anoxia. Late Ordovician and Late Devonian black mudstones that cover much of Laurentia record epeirogenic transgressions that led to global hyperwarming, and suggest that cold water upwelling or plant terrestrialisation had nothing to do with epeiric sea anoxia. Global hyperwarming reduced oxygen solubility in these seas, and erosion of orogens produced muddy water that limited light penetration and promoted shallow-water anoxia. The global hyperwarming hypothesis means that relative eustatic and epeirogenic sea levels complement the effect of global pCO 2 on climate, and sea level must also be regarded as a primary driver of Phanerozoic climate.

Facies relationshps in the Vendian to Lower Cambrian Chapel Island Formation of southeast Newfoundland are used to establish a sequence stratigraphic framework for this important boundary stratotype section. The formation consists of five members of sandstone, mudstone and minor limestone deposited in a variety of shoreline to shelf environments. Peritidal sandstone and shale units in member 1 are overlain by sandstone and silstone deltaic and shelf deposits of member 2. These make up a transgressive system tract in which small-scale changes in relative sea level are superimposed on autocyclic deltaic processes. The thickness (> 400 m) of nearshore and inner shelf sediments resulted from high sediment accumulation rates which for member 2 nearly kept pace with subsidence. Upper member 3 and member 4 consist of inner shelf mudstone and peritidal limestone that were deposited in a low-energy oxygen-stratified basin. These deposits are arranged in three large-scale shoaling cycles representing three foresteping parasequences of one highstand systems tract. An extensive limestone bed at the tope of member 4 contains a sequence boundary. Associated with, or shortly postdating, development of this surface is a significant epeirogenic event that resulted in basin reorganization, increased subsidence, and progradation of a thick clastic sequence represented by member 5. The deposits of this upper member consist of an upward-coarsening storm-dominated shelf to shoreface succession of sandstone and silstone. Deposits of nearly identical character are also found in New Brunswick, and suggest that these sediments and the underlying sequence boundary could be significant for interregional correlation. Global correlation of the paleobathymetric curve developed for the Chapel Island Formation is considered unfeasible, given the long history of epeirogenic movements during the Vendian and Early Cambrian in this region.

A synthesis of personal research concerning the peri-Pyrenean region and previously published data is presented as a series of palaeogeographic reconstructions. Subsequent to the progressive regression at the end of the Cretaceous the sea invaded three times parts of the earlier Senonian marine domain on both sides of the eastern Palaeo-Pyrenees. Pre-Cuisian climatic rewarming combined with Cuisian continental epeirogenic deformations resulted in major biogeographic modifications. During the Cuisian local tectonics forced the sea from the northern Pyrenean basin whereas in the southern Pyrenean basin the sea retreated much later as a consequence of the Pyrenean tectonic phase. However, the Pyrenean tectogenesis seems to have affected a much larger region, including the Alps. Shoreline migrations are compared and related to the geodynamic behaviour of the meridional and septentrional European provinces, in order to distinguish between tectonic and eustatic causes.

The evolution of the east coast of India from the Permian up to the end of the Cretaceous is traced. Peninsular India had an imprint of Hercynian epeirogeny, manifested in the formation of some regional geofracture and rift systems. The east coast basins (Mahanadi, Godavari-Krishna, Palar and Cauvery Basins) are pericratonic. The structural style and regional trends during the Jurassic are NE-SW. The basin architecture during the Late Jurassic is of horst-graben type. The close of the Mesozoic was marked by regional easterly regression, basinal tilt and formation of monoclinal post-Mesozoic sedimentary cover. The oldest sequence in these basins is of Permian age and is known in the Palar Basin. The Triassic sediments are not known in the land area. From the faunistic and floristic evidence, the ? Uppermost Jurassic—Lower Cretaceous (Gondwana) sediments are paralic. The occurrence of marine Permian palynofossils in the Indian east coast sediments points to the presence of a narrow paleo-shelf to the east prior to the break-up and drift of Gondwanaland. Different continental fits offered by various authors are analysed to understand the evolution of the Indian ocean. The structural grain and basin architecture of the pre-drift and post-drift basins of the east coast of India are similar to that of the western and northwestern coastal basins of Australia. It is postulated that Permian sediments were extensive and have since been eroded. Such a pattern of erosion of Permian beds is also observed in northwestern Australia. The most favoured fit of Western Australia against northern India does not conform to the regional geotectonic pattern and the nature of sediments that are present in India and the Australian counterparts. In addition to geological evidence, palaeo-biological evidence has been considered which favours the juxtaposition of the east coast of India with Western Australia. The authors are of the opinion that palaeomagnetic interpretations, which have of late gained importance, fail to explain the pre-drift geological similarities of the east coast of India and western coast of Australia.

This paper reviews the timing of volcanic and epeirogenic events in the North Atlantic area during the Palaeogene with special emphasis on East Greenland. An appraisal of existing radiometric ages leads to the conclusion that onshore volcanism was of an episodic nature, being either limited to, or concentrated around, the following ages: 65 m.y. (anomaly 30), 60 m.y. (anomaly 26), 55 m.y. (anomaly 24), 50 m.y. (anomaly 21), 35 m.y. (anomaly 13) and 28 m.y. (anomaly 9?). In some cases (55 and 35 m.y.) these episodes appear to correspond to widespread plate tectonic events, in other cases (50 and 35 m.y.) to more localized epeirogenic movements. A consideration of the physiography of East Greenland shows that at least two epeirogenic events have been significant. One of these raised a dome 300 km across and 4 km above its surroundings and the other elevated a plateau of regional extent some 2.5 km above sea level. A variety of evidence tentatively dates these events to 50 m.y. and 35 m.y. respectively. The recognition and dating of these events is a contribution towards an understanding of the fine-scale sequence of events during continental break-up and subsequent ocean basin development. The conclusions are tentative due to inadequate data at the present time, especially from the offshore area.

With the breakup of Gondwanaland a northwards-transgressing sea reached southern Mozambique in mid-Cretaceous times. The deeply weathered Karoo volcanics of southern Mozambique are overlain by glauconitic silty sandstones of Barremian to Cenomanian age, with marginal disconformities in the lowest and uppermost Albian. After a late Cenomanian to Turonian hiatus, with local deposition of continental sediments, the marine facies reappeared with silty sandstones. In the south these sandstones are of Coniacian age, becoming younger to the north, where only the Campanian or Maestrichtian are represented. A minor unconformity is present within the Upper Maestrichtian—Lower Paleocene sequence. Shallow-water sediments indicate a further regression in late Eocene times. Oligocene sediments appear only in the deeper parts of the basin. A last transgression occurred in the Early Miocene. Single local ingressions might have followeduntil the Pliocene. Since the Pliocene, a general epeirogenic uplift of the South African subcontinent, combined with the tectonic activity of the East African Rift, led to a period of erosion. The Quaternary is characterized by a thick cover of eolian sands. The geological history, stratigraphy and paleogeography on both sides of the Mozambique Channel, and recent results of deep-sea drilling in the channel, suggest a more or less unchanged position of Madagascar relative to Africa since the Late Paleozoic.

A plot of known exposures of coastal sediments, showing approximate age and present elevation, provides one approach to the history of sea level, in the southeastern states, through Late Cretaceous and Tertiary time. Five important pre-Pleistocene points appear on this plot; on semi-log paper, they define two straight-line segments. The first segment covering Late Cretaceous and Tertiary pre-Miocene time, indicates a drop of sea level or an equivalent rise of the land area of about 50 m in 70 · 10 6 years, or 0.7 mm/10 3 years. The second segment, for Mio-Pliocene time, indicates an additional drop in sea level of about 75 m in 25 · 10 6 years, or about 3 mm/10 3 years. Pleistocene fluctuations are not included in this plot. The first segment is thought to represent a net isostatic rebound due largely to erosional unloading of the southern Appalachians. The second segment is thought to represent a glacio-eustatic change, probably due to ice accumulation in near-polar areas such as Antarctica. Because the control points are few and uncertain, only a very rough approximation to sea-level history can be obtained in the area of interest. There is a very real possibility that local structural effects have contributed an unknown bias to the results. In any event, it does not seem possible to separate various types of epeirogenic and tectonic influences. Nevertheless, the two line segments are sufficiently different in slope and character to require two different processes, and the glacio-eustatic explanation for the second segment is the most attractive one available. Two highly simplified equations are developed, one describing each line segment. Use of these equations produces two interesting hypotheses: ( a ) total net isostatic rebound in the southern Appalachians due to erosional unloading, has been 500–600 m since later Pennsylvanian time; and ( b ) if glacio-eustatic events had not modified the isostatic curve, since Middle Miocene time, sea level would now stand at about +68 m.