Map and cross sections of coal zones in the Upper Cretaceous Neslen and Mount Garfield formations, northeastern part of the Westwater 30' x 60' Quadrangle and adjacent area, Garfield County, Colorado, and Grand and Uintah counties, Utah

1991 ◽  
Keyword(s):  
Cross Sections ◽  
Upper Cretaceous ◽  
Adjacent Area ◽  
Northeastern Part ◽  
Garfield County

Climatic Changes in the Qinghai-Xizang (Tibetan) Region of China during the Holocene

1987 ◽  
Vol 28 (1) ◽  
pp. 50-60 ◽  
Author(s):  
Wang Fu-Bao ◽  
C. Y. Fan
Keyword(s):  
Cross Sections ◽  
Little Ice Age ◽  
Climatic Changes ◽  
Northern Region ◽  
Ice Age ◽  
Southern Slope ◽  
The Holocene ◽  
Northeastern Part ◽  
Xizang Plateau ◽  
Sand And Gravel

AbstractClimatic changes in the Qinghai-Xizang Plateau of China were studied by analyzing the composition of peat and layers of sand and gravel distributed along the southern slopes of Nianqing-Tanggula and Gangdise Mountains, cross sections of deposits near a number of interior lakes in Xizang, past glacial variations on the southern slope of Nianqing-Tanggula Mountain, and landform changes south of the Yaluzangbu River. Such geologic evidence suggests a division of five climatic periods since the beginning of the Holocene: (1) The Wumadung interval, 10,000–7500 yr B.P., slightly cold and dry; (2) Qilongduo interval, 7500-3000 yr B.P., warm and moist; (3) the mid-Neoglacial period, 3000-1500 yr B.P., cold, except between 2500 and 200 yr B.P. when it was warmer; (4) the Dawelong interval, 1500-300 yr B.P., mild; and (5) the Little Ice Age, 300-0 yr B.P., cold. These changes progressed in a similar but not identical pattern as those in the northeastern part of China and in the northern region of Europe.

Building a structural image in the Elward area in the Syrian Euphrates Graben using 3D seismic data

2016 ◽  
Vol 4 (1) ◽  
pp. T63-T77
Author(s):  
Rabah Shaheen ◽  
Riad Taifour ◽  
Mohammad Alsouki
Keyword(s):  
Cross Sections ◽  
Seismic Data ◽  
Upper Cretaceous ◽  
Structural Deformation ◽  
Late Triassic ◽  
3D Seismic ◽  
Restoration Techniques ◽  
Structural Image ◽  
Triassic Period ◽  
3D Seismic Data

By generating fault maps, isochron maps, and applying restoration techniques to 3D seismic data acquired over the Elward area of Syria, we have built a suite of cross sections that represent the tectonic evolution of the area. Fault maps and time structure maps reveal structural deformation, whereas isochron maps define areas of fault-controlled depocenters. Seismic attributes delineate fluvial channels formed during the Late Triassic period. The main rift phase in the study area is the Upper Cretaceous (Coniacian). Our analysis explained the absence of the Judea and the upper part of the Rutbah Formations from the stratigraphic column of the Elward north field.

Eastern Boulder-Weld fault zone, Colorado: A gravity slide with pop-up structures

2020 ◽  
Vol 57 (3) ◽  
pp. 177-198
Author(s):  
Richard H. Groshong ◽  
Ken Kittleson
Keyword(s):  
Fault Zone ◽  
Cross Sections ◽  
Upper Cretaceous ◽  
Sedimentary Rocks ◽  
Detailed Examination ◽  
Contour Map ◽  
Pierre Shale ◽  
Structural Style ◽  
Transport Direction ◽  
Gravity Slide

The Boulder-Weld fault zone, located southeast of Boulder, Colorado, is about 10 km (6 mi) wide, 34 km (21 mi) long, and involves at least 335 m (1100 ft) of upper Cretaceous sedimentary rocks. It affects the Cretaceous upper Pierre Shale, Fox Hills Sandstone, and the coal–bearing lower Laramie Formation. This study is a detailed examination of the eastern portion of the fault zone which consists of undisturbed areas separated by three long, narrow, fault-bounded uplifts that have received a variety of interpretations over the years. The fault zone geometry is determined from 21 closely spaced cross sections that use more subsurface data than previous studies, incorporate the elevations of the major economic coal seam derived from a published composite structure-contour map, and are area balanced using area-depth-strain (ADS) analysis. The most common structural style is a pop-up structure in which the uplifts are bounded on both sides by reverse faults. At larger-displacement the pop-ups are at the tip of the ramp and a second fault has formed close to the base of the ramp. A few sections show simple ramp anticlines developed above listric thrusts. The lower detachment for all structures is the distinctive Kp2 marker in the upper Pierre Shale. ADS analysis of the best-controlled uplifts shows that the uplifts are area balanced and confirms the lower detachment to be near Kp2. The structures are interpreted to have formed as a gravity slide because they formed in a break-back sequence, a characteristic of gravity gliding, and because the transport direction is approximately down the current southeast dip of the Kp2 detachment.

CASE HISTORY OF WILD GOOSE GAS FIELD, BUTTE COUNTY, CALIFORNIA

Geophysics ◽  
1954 ◽  
Vol 19 (3) ◽  
pp. 509-516 ◽  
Author(s):  
Wallace L. Matjasic
Keyword(s):  
Cross Sections ◽  
Seismic Reflection ◽  
Upper Cretaceous ◽  
Gas Field ◽  
Contour Map ◽  
Seismic Reflection Data ◽  
Reflection Data ◽  
History Of ◽  
Further Development ◽  
Wild Goose

The discovery well of the Wild Goose gas field was drilled and completed in 1951 on a structure located by a reflection seismograph survey conducted in 1950. An additional seismograph survey was made subsequent to discovery to define the structure better for further development. The illustrations include two seismic cross sections, a contour map based on the original seismic reflection data, an aeromagnetic map, a structure contour map, and an electric log of the discovery well. The producing sands are in an interval between the Forbes shale of Upper Cretaceous age and the overlying Capay shale of Eocene age.

Sign in / Sign up

Export Citation Format

Share Document