Western Interior Seaway, caused the western coastal plain rivers to return to 

 grade by depositing a coarse fluvial sandstone (Torrivio Mbr of the Gallup 

 Sandstone), enhanced the bypassing of fines, and intensified storm- induced 

 coarse-grained sediment transport onto the distal shelf (Cooper Arroyo and 

 basal Tocito Sandstones) . The subsequent transgression resulted in shoreface 

 retreat by destruction of distributary mouth bars of the Torrivio Mbr, 

 formation of offshore linear shelf sand ridges above the ravinement diastem 

 (Tocito Sandstone ridges) , the deposition of a series of transgressive sand 

 bodies in back-barrier settings (e.g., flood-tidal deltas of the Borrego Pass 

 Sandstone) , and rapid accretion of low-energy fluvial facies (Dilco Coal Mbr 

 of the Crevasse Canyon Fm) . Individual ravinement surfaces underlie many 

 Tocito Sandstone ridges and separate them from regressive facies, but these 

 surfaces may be of limited areal extent and are probably not connected to a 

 single regional unconformity. The ravinement surfaces and the transgressive 

 Tocito sandstones climb progressively higher in the section relative to the 

 mid-Coniacian sequence boundary as one moves updip (paleo - landward) . 

 (Authors) . 



250 OERLEMANS, J. 1981. "Effects of Irregular Fluctuations in Antarctica 

 Precipitation on Global Sea-Level," Nature . Vol 290, pp 770-772. 



One of the reasons for the continuing interest in the global sea- level is 

 that secular variations may be caused by climatic changes. Such a change 

 could, for example, be an atmospheric warming due to CO accumulation. Changes 

 in the amount of ice in the major ice sheets will be reflected in secular 

 variations of sea-level; it has, for example, been suggested that ice-shelf 

 thinning may change the drainage of parts of the Antarctic Ice Sheet. At- 

 tempts to monitor climatic change by measuring global sea-level will, however, 

 be complicated by random variations in the ice accumulation rate. Precipita- 

 tion rates are highly variable, and this also applies to Antarctica, which 

 stores most of the continental ice mass. By means of a simple model for ice 

 flow in the Antarctica, together with proxy data on precipitation variability 

 derived from ice cores, I show that long-term sea- level variations with a 

 standard deviation of roughly 5 cm are to be expected on this account. This 

 "climatic noise" is comparable in magnitude with many of the secular effects 

 now being sought. (Author). 



251 OFFICER, C. B., and DRAKE, C. L. 1985. "Terminal Cretaceous 

 Environmental Events," Science, Vol 227, No. 4691, pp 1161-1167. 



The geologic record of terminal Cretaceous environmental events indicates 

 that iridium and other associated elements were not deposited instantaneously 

 but during a time interval spanning some 10,000 to 100,000 years. The 

 available geologic evidence favors a mantle rather than meteoritic origin for 

 these elements. These results are in accord with the scenario of a series of 

 intense eruptive volcanic events occurring during a relatively short geologic 

 time interval and not with the scenario of a single large asteroid impact 

 event. (Authors). 



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