Podcast
Questions and Answers
What sedimentary structures characterize the sandstone bed in the Kudat Peninsular?
What sedimentary structures characterize the sandstone bed in the Kudat Peninsular?
The sandstone bed is characterized by parallel lamination, ripple marks, convolute structures, and water structures.
Describe the composition of the Sikuati Member.
Describe the composition of the Sikuati Member.
The Sikuati Member consists of interbedded fine-grained sandstone and mudstone with abundant sedimentary structures such as parallel lamination, cross lamination, and wavy lamination.
What type of rocks are included in the mélange unit found in the Kudat Peninsular?
What type of rocks are included in the mélange unit found in the Kudat Peninsular?
The mélange unit includes serpentinite, chert, and red mudstone.
What are knockers in the context of the mélange unit?
What are knockers in the context of the mélange unit?
Signup and view all the answers
What does the presence of slickensides on serpentinite indicate?
What does the presence of slickensides on serpentinite indicate?
Signup and view all the answers
How can the age of the mélange unit be determined?
How can the age of the mélange unit be determined?
Signup and view all the answers
What geological formation does the Tajau Member contribute to in the Kudat Peninsular?
What geological formation does the Tajau Member contribute to in the Kudat Peninsular?
Signup and view all the answers
What is the significance of identifying sedimentary structures like wavy boundaries or sharp straight boundaries in rock beds?
What is the significance of identifying sedimentary structures like wavy boundaries or sharp straight boundaries in rock beds?
Signup and view all the answers
What types of rocks are associated with basalt and spilite?
What types of rocks are associated with basalt and spilite?
Signup and view all the answers
What is the geological age of the oceanic crust interpreted from the basement rock in this region?
What is the geological age of the oceanic crust interpreted from the basement rock in this region?
Signup and view all the answers
How are the Crocker and Trusmadi Formations characterized?
How are the Crocker and Trusmadi Formations characterized?
Signup and view all the answers
What distinguishes the Kudat Formation from the Crocker and Trusmadi Formations?
What distinguishes the Kudat Formation from the Crocker and Trusmadi Formations?
Signup and view all the answers
What types of deposits make up the Bongaya Formation?
What types of deposits make up the Bongaya Formation?
Signup and view all the answers
During which geological time were the igneous rocks on Sirar Island formed?
During which geological time were the igneous rocks on Sirar Island formed?
Signup and view all the answers
What geological feature divides the turbidites in the Crocker Formation?
What geological feature divides the turbidites in the Crocker Formation?
Signup and view all the answers
What geological process likely occurred during the Miocene affecting the Crocker Range?
What geological process likely occurred during the Miocene affecting the Crocker Range?
Signup and view all the answers
What sedimentary structures are present in the sandstone beds mentioned in the content?
What sedimentary structures are present in the sandstone beds mentioned in the content?
Signup and view all the answers
In the geological context provided, how are the Temburong and Crocker Formations related?
In the geological context provided, how are the Temburong and Crocker Formations related?
Signup and view all the answers
What geological ages are assigned to the Temburong and Crocker Formations?
What geological ages are assigned to the Temburong and Crocker Formations?
Signup and view all the answers
Discuss the age range of the Meligan Formation and its significance.
Discuss the age range of the Meligan Formation and its significance.
Signup and view all the answers
How is the Liang Formation characterized in relation to the Meligan Formation?
How is the Liang Formation characterized in relation to the Meligan Formation?
Signup and view all the answers
What type of foraminifera is mentioned in relation to the Temburong Formation?
What type of foraminifera is mentioned in relation to the Temburong Formation?
Signup and view all the answers
What is the primary mineral composition of the Meligan Formation as described?
What is the primary mineral composition of the Meligan Formation as described?
Signup and view all the answers
What is the geological significance of the similarity in lithology units between the Temburong and Crocker Formations?
What is the geological significance of the similarity in lithology units between the Temburong and Crocker Formations?
Signup and view all the answers
What is the significance of Sabah's geographic location in terms of tectonic plates?
What is the significance of Sabah's geographic location in terms of tectonic plates?
Signup and view all the answers
Name the three marginal basins surrounding Sabah.
Name the three marginal basins surrounding Sabah.
Signup and view all the answers
What are the main tectonic elements in the western part of Sabah?
What are the main tectonic elements in the western part of Sabah?
Signup and view all the answers
Describe the depositional environment change observed during the Early Miocene in Sabah.
Describe the depositional environment change observed during the Early Miocene in Sabah.
Signup and view all the answers
What geological event is associated with the collision of the Cagayan Arc and Palawan micro-continental block?
What geological event is associated with the collision of the Cagayan Arc and Palawan micro-continental block?
Signup and view all the answers
What tectonic activity characterized the Late Miocene period in Sabah?
What tectonic activity characterized the Late Miocene period in Sabah?
Signup and view all the answers
What type of rocks are found in Sabah from the Pre-Cenozoic era?
What type of rocks are found in Sabah from the Pre-Cenozoic era?
Signup and view all the answers
What role does gravity data play in understanding Sabah's geological structure?
What role does gravity data play in understanding Sabah's geological structure?
Signup and view all the answers
What type of tectonic movements contributed to the structural development in the Sabah region during the Late Miocene?
What type of tectonic movements contributed to the structural development in the Sabah region during the Late Miocene?
Signup and view all the answers
During which geological period did significant strike-slip deformation occur in Sabah and its neighboring regions?
During which geological period did significant strike-slip deformation occur in Sabah and its neighboring regions?
Signup and view all the answers
What were the two major tectonic features mentioned that characterize the Late Eocene tectonic deformation in Sabah?
What were the two major tectonic features mentioned that characterize the Late Eocene tectonic deformation in Sabah?
Signup and view all the answers
What is the significance of the Early Miocene deformation in the tectonic evolution of Sabah?
What is the significance of the Early Miocene deformation in the tectonic evolution of Sabah?
Signup and view all the answers
How did the tectonic events from the Late Eocene to Middle Miocene influence the geological structures in Sabah?
How did the tectonic events from the Late Eocene to Middle Miocene influence the geological structures in Sabah?
Signup and view all the answers
What connection exists between the Kuamut Formation and tectonic activity during the Late Oligocene?
What connection exists between the Kuamut Formation and tectonic activity during the Late Oligocene?
Signup and view all the answers
What deformation is attributed to the transpressional movement noted in the Sabah region's late geological history?
What deformation is attributed to the transpressional movement noted in the Sabah region's late geological history?
Signup and view all the answers
Which tectonic activity is associated with the subduction of the proto-South China Sea?
Which tectonic activity is associated with the subduction of the proto-South China Sea?
Signup and view all the answers
The Crocker Formation turbidites sit on the Eocene ______ Formation.
The Crocker Formation turbidites sit on the Eocene ______ Formation.
Signup and view all the answers
The northern part of Sabah has sedimentary and igneous rocks of Early Cretaceous to ______ age.
The northern part of Sabah has sedimentary and igneous rocks of Early Cretaceous to ______ age.
Signup and view all the answers
The elongate basin that formed during the Late Cretaceous to Early Eocene was the site for the deposition of middle Eocene to Early ______ quartzose sediments.
The elongate basin that formed during the Late Cretaceous to Early Eocene was the site for the deposition of middle Eocene to Early ______ quartzose sediments.
Signup and view all the answers
Kudat Peninsula comprises four formations, one of which is the ______ Formation.
Kudat Peninsula comprises four formations, one of which is the ______ Formation.
Signup and view all the answers
The offshore islands of KK expose ______ turbidites.
The offshore islands of KK expose ______ turbidites.
Signup and view all the answers
The basemant rock of this part of Sabah is an ophiolite ______, probably of Cretaceous age.
The basemant rock of this part of Sabah is an ophiolite ______, probably of Cretaceous age.
Signup and view all the answers
The Gomantong Member is referred to as the Upper Unit of the ______ Formation.
The Gomantong Member is referred to as the Upper Unit of the ______ Formation.
Signup and view all the answers
Three major episodes of deformation have affected the northern part of Sabah, associated with NW-SE and N-S oriented ______.
Three major episodes of deformation have affected the northern part of Sabah, associated with NW-SE and N-S oriented ______.
Signup and view all the answers
The main tectonic elements of Sabah include a major fold-thrust belt trending northeast in the west known as the ______ Trend.
The main tectonic elements of Sabah include a major fold-thrust belt trending northeast in the west known as the ______ Trend.
Signup and view all the answers
During the Middle Miocene, the collision of the ______ Arc and Palawan micro-continental block caused a significant tectonic event.
During the Middle Miocene, the collision of the ______ Arc and Palawan micro-continental block caused a significant tectonic event.
Signup and view all the answers
The tectonic evolution of Sabah has been significantly influenced by rifting of the ______ Sea during the Late Early Miocene.
The tectonic evolution of Sabah has been significantly influenced by rifting of the ______ Sea during the Late Early Miocene.
Signup and view all the answers
The two main sedimentary formations mentioned are the ______ Formation and the Umas-Umas Formation.
The two main sedimentary formations mentioned are the ______ Formation and the Umas-Umas Formation.
Signup and view all the answers
The presence of ______ rocks in Sabah is interpreted to reflect its complex geological history and possible continental origin.
The presence of ______ rocks in Sabah is interpreted to reflect its complex geological history and possible continental origin.
Signup and view all the answers
The ______ sediments found in coastal areas of Sabah include limestones, calcareous sandstone, and conglomerates.
The ______ sediments found in coastal areas of Sabah include limestones, calcareous sandstone, and conglomerates.
Signup and view all the answers
The major uplift and erosion events in Sabah produced what is known as the Base ______ Unconformity.
The major uplift and erosion events in Sabah produced what is known as the Base ______ Unconformity.
Signup and view all the answers
The tectonic features of Sabah are influenced by its position at the junction of the ______, Indo-Australian, Pacific, and Philippines Sea plates.
The tectonic features of Sabah are influenced by its position at the junction of the ______, Indo-Australian, Pacific, and Philippines Sea plates.
Signup and view all the answers
The Eastern Sabah is considered one of the largest mélange (olistostrome) terrane in the world, covering approximately ______ sq km.
The Eastern Sabah is considered one of the largest mélange (olistostrome) terrane in the world, covering approximately ______ sq km.
Signup and view all the answers
The lithology of the mélange mainly comprises mud-matrix olistostrome and broken formations including ______ and tuffaceous layers.
The lithology of the mélange mainly comprises mud-matrix olistostrome and broken formations including ______ and tuffaceous layers.
Signup and view all the answers
The uplifted Crystalline Basement and ophiolitic Chert-Spilite Formation likely acted as a barrier ridge separating the NE Sabah Basin from the ______ Sabah Basin.
The uplifted Crystalline Basement and ophiolitic Chert-Spilite Formation likely acted as a barrier ridge separating the NE Sabah Basin from the ______ Sabah Basin.
Signup and view all the answers
Volcanic activity in the Semporna and Dent Peninsula occurred from the early Miocene to ______.
Volcanic activity in the Semporna and Dent Peninsula occurred from the early Miocene to ______.
Signup and view all the answers
The occurrences of volcanic rocks in the Semporna area are believed to be the southwest onshore continuation of the ______ Arc.
The occurrences of volcanic rocks in the Semporna area are believed to be the southwest onshore continuation of the ______ Arc.
Signup and view all the answers
The Tanjong and Kapilit formations are exposed in circular, sub-circular, and ______ basins.
The Tanjong and Kapilit formations are exposed in circular, sub-circular, and ______ basins.
Signup and view all the answers
The late Middle to early Late Miocene was marked by uplifts and erosion of the Tanjong formation, leading to another cycle of sediment filling in the ______ Sub-basin.
The late Middle to early Late Miocene was marked by uplifts and erosion of the Tanjong formation, leading to another cycle of sediment filling in the ______ Sub-basin.
Signup and view all the answers
The Dent Groups of sediments primarily consist of clastics with minor ______.
The Dent Groups of sediments primarily consist of clastics with minor ______.
Signup and view all the answers
The Labang and Kulapis formations represent deposition of deep-water clastics in a ___ basin setting.
The Labang and Kulapis formations represent deposition of deep-water clastics in a ___ basin setting.
Signup and view all the answers
During the Oligocene, there was widespread regional ___.
During the Oligocene, there was widespread regional ___.
Signup and view all the answers
The Early Miocene was a period of progressive tectonic ___ in the forearc region.
The Early Miocene was a period of progressive tectonic ___ in the forearc region.
Signup and view all the answers
Inclusion of Labang Formation sandstone and mudstone clasts in the Gomantong Limestone demonstrates that uplift and ___ started by the Early Miocene.
Inclusion of Labang Formation sandstone and mudstone clasts in the Gomantong Limestone demonstrates that uplift and ___ started by the Early Miocene.
Signup and view all the answers
The base Miocene unconformity is interpreted as a major tectonic event caused by the subduction and collision of the Dangerous Ground Continental ___.
The base Miocene unconformity is interpreted as a major tectonic event caused by the subduction and collision of the Dangerous Ground Continental ___.
Signup and view all the answers
This tectonic event is referred to as the ‘___ Orogeny’ related to the interaction of tectonic plates.
This tectonic event is referred to as the ‘___ Orogeny’ related to the interaction of tectonic plates.
Signup and view all the answers
Deformation continued for several million years, with the Gomantong Limestone forming on structural ___ during relatively quiescent times.
Deformation continued for several million years, with the Gomantong Limestone forming on structural ___ during relatively quiescent times.
Signup and view all the answers
The associated major uplift and erosion provided sediment supply to the deltaic to shallow marine Middle to Upper ___ successions.
The associated major uplift and erosion provided sediment supply to the deltaic to shallow marine Middle to Upper ___ successions.
Signup and view all the answers
The present outcrop pattern of the Miocene strata is the product of regional ______ and transpressional tectonics.
The present outcrop pattern of the Miocene strata is the product of regional ______ and transpressional tectonics.
Signup and view all the answers
The Late Eocene tectonic deformation is characterized by ______ and thrusting of basement rock.
The Late Eocene tectonic deformation is characterized by ______ and thrusting of basement rock.
Signup and view all the answers
At least three major episodes of tectonic events in Sabah are linked to NW-SE ______ coinciding with subduction.
At least three major episodes of tectonic events in Sabah are linked to NW-SE ______ coinciding with subduction.
Signup and view all the answers
The Early Miocene deformation is interpreted to mark a major tectonic event, causing the formation of ______ and major uplift.
The Early Miocene deformation is interpreted to mark a major tectonic event, causing the formation of ______ and major uplift.
Signup and view all the answers
The Kuamut Formation has been linked to sedimentation on the flanks of an accretionary ______ in Late Oligocene times.
The Kuamut Formation has been linked to sedimentation on the flanks of an accretionary ______ in Late Oligocene times.
Signup and view all the answers
The Late Miocene deformation is interpreted to be caused by major ______ deformation in the Sabah region.
The Late Miocene deformation is interpreted to be caused by major ______ deformation in the Sabah region.
Signup and view all the answers
Tectonic evolution in Sabah has occurred since the Early ______.
Tectonic evolution in Sabah has occurred since the Early ______.
Signup and view all the answers
The paleogene regional tectonic setting of Sabah seems to be very ______, with different subduction and extension processes.
The paleogene regional tectonic setting of Sabah seems to be very ______, with different subduction and extension processes.
Signup and view all the answers
Study Notes
Introduction
- The text describes the geological history of Sabah, Malaysia, analyzing the rock formations and explaining their formation by tectonic events.
- Sabah is located in a tectonically active region, at a junction of multiple plates, and has a complex geological evolution.
Rock Formations and Stratigraphy
- The basement rock in Sabah is comprised of an oceanic crust from the Mesozoic era, formed from ophiolite series.
- The basement rock is overlain by Eocene to Early Miocene sedimentary rocks, including the Crocker, Trusmadi, and Kudat Formations.
-
Crocker Formation: Found in Western Sabah; deep-water flysch sediments, characterized by rhythmic alternation of sandstone and shale beds.
- Turbidites within the formation reach 1,000m thick and were deposited in a deep-water basin (submarine fan) during the latest Eocene (37 Ma) to the earliest Miocene (21 Ma).
- The Crocker Range is deformed by high-angle reverse faults that formed during the Miocene.
- Trusmadi Formation: Found in Western Sabah with similar composition to the Crocker Formation.
-
Kudat Formation: Located in Northern Sabah; shallow-water sediments with interbedded carbonaceous sandstones and shales, containing Eocene-Early Miocene limestone bioherms.
- The Kudat Peninsula exhibits unique geological features:
- Sikuati Member: Interbedded fine-grained sandstone and mudstone with abundant sedimentary structures like parallel, cross, and wavy lamination.
- Tajau Member: Thick sandstone beds interbedded with thin mudstone layers, forming the northern Kudat terrane.
- Melange Unit: Found in the northern part of the peninsula, consisting of intensely deformed ophiolitic basement rock, serpentinite, chert, and red mudstone, creating chaotic outcrops known as "knockers".
- The mélange unit is estimated to be Middle Miocene in age based on the presence of Cyclicargolithus floridanus.
- The Kudat Peninsula exhibits unique geological features:
Bongaya Formation
- Upper Miocene in age; shallow-water deposits of sandstones, shales, limestone, and conglomerates.
- Occurs in Northern Sabah, overlying the basement rock and Crocker and Kudat Formations.
- Unconformably overlain by the Pliocene-Pleistocene Timohing Formation on Balambangan Island.
Southwest Sabah
- The area between Weston and Sipitang consists of four formations: Temburong, Crocker, Meligan, and Liang.
- Previously considered stratographically higher than the Crocker Formation, the Temburong Formation is now reinterpreted as underneath it.
- Both the Temburong and Crocker Formations are dated as Upper Eocene to Lower Miocene, while the Meligan Formation is Middle Miocene to Upper Miocene, and Liang Formation is Pliocene in age.
Igneous Rocks in Sabah
- Miocene-Pliocene timeframe saw the formation of both intrusive (Mt. Kinabalu plutonics) and extrusive (Sirar Island volcanics) igneous rocks.
Eastern Sabah
- Plio-Pleistocene sediments in coastal areas include limestones, calcareous sandstone, conglomerate, carbon shale.
- These sediments belong to the Sandakan, Bongaya, Simengaris, Umas-Umas, and Balung Formations.
- The Togopi and Wallace Formations are also part of this group.
Tectonic Evolution
- Sabah lies at a critical intersection of multiple plates: Eurasian, Indo-Australian, Pacific, and Philippine Sea plates.
- The region is also situated among three marginal basins: the Sulu, Celebes, and South China Seas.
- Sabah's tectonic evolution is characterized by:
- A northeast trending fold-thrust belt in the west (NW Borneo Trend) and a southeast bend (Sulu Trend) in the north and eastern part of Sabah.
- The Early Miocene deformation is a significant tectonic event, leading to the formation of mélanges, major uplift, and erosion, creating the Base Miocene Unconformity.
- The NW-SE rifting of the Sulu Sea (Late Early Miocene) rejuvenated the Central Sabah Basin, initiating rift basins in a back-arc setting.
- The collision of the Cagayan Arc and Palawan micro-continental block (Middle Miocene) created another unconformity, marked as the Deep Regional Unconformity.
- A Late Miocene tectonic event led to folding and uplift, defining the Shallow Regional Unconformity.
- The latest tectonic event involved strike-slip faulting and transpressional fault movement, continuing from the Pliocene to the present day.
Pre-Cenozoic
- Presence of granitic and metamorphic rocks of potential continental origin associated with the ophiolitic complex.
- Gravity data suggests continental basement lies beneath the ophiolite.
- Present outcrop patterns of Miocene strata are a result of regional strike-slip and transpressional tectonics and inversion during the Late Miocene (8.6 Ma) and continued into the Late Pliocene.
Late Miocene Deformation and Uplift
- Transpressional movement along the major strike-slip faults is responsible for the structural development in the region, potentially linked to deformation propagation from Sulawesi towards NW Sabah.
- Late Pliocene strike-slip deformation is regionally significant and occurred concurrently with deformation in NE Kalimantan, Sulawesi, and NW Sabah.
- This transpressional movement is the driving force behind significant orogenic deformation, uplift, and structural development in Sabah, likely persisting to the present day.
Key Tectonic Events Throughout Sabah's History
-
Early Tertiary: Marked by several regional tectonic events resulting in diverse structural trends and depositional frameworks in Sabah.
-
At least three major episodes associated with NW-SE compression occurred:
- Late Eocene: Folding and thrusting of basement rock and older paleogene sediments.
- Early Miocene: Formation of the mélanges, major uplift, and erosion, creating the Base Miocene Unconformity, a change in depositional environment from deepwater to a shallow deltaic.
- Middle Miocene: Another major unconformity (Deep Regional Unconformity) due to collision of the Cagayan Arc and Palawan micro-continental block.
-
The Late Eocene tectonic setting in Sabah was complex, with southeasterly subduction in NW Borneo and extension in the SE in the Celebes Sea and Makassar Strait. These various events contribute to the complex and diverse geology of Sabah.
Crocker Formation
- Made up of quartz-rich sandstones, with beds ranging from tens of centimeters to a few meters thick
- Located on top of the Eocene Trusmadi Formation, which consists of thick dark shale beds with thin sandstone layers
- The relationship between the two formations is likely an unconformity
- Lies on top of an ophiolite mélange (ocean-floor subduction rocks) of possible Cretaceous age
Kudat Peninsula
- Composed of four formations: Ophiolitic Basement, Crocker Formation, Kudat Formation, and a mélange unit
- Dominated by the Kudat Formation, which contains deep to shallow water sediments
- Gomantong, Sikuati, and Tajau Members of the Kudat Formation are made up of interbedded sandstone and mudstone
- The Gomantong Member is considered the youngest member of the Kudat Formation
Eastern Sabah
- Has chaotically disrupted rock units covering approximately 12,000 square kilometers
- Contains one of the world's largest mélange (olistostrome) terranes
- Lithology primarily consists of mud-matrix olistostrome and broken formations, including tuff and tuffaceous layers
- Broken formations are known as Kuamut, Garinono, Ayer, and Kalabakan formations
- Olistostrome were formed by slumping into a deep marine basin
- Explosive volcanism accompanied olistostrome deposition, as evidenced by the abundance of tuffaceous material in Kuamut, Garinono, and especially the Ayer Formation
Northern Tarakan Sub-basin
- Contains Tanjong and Kapilit formations
- Exposed in circular, sub-circular, and synclinal basins
- Predominantly consists of deltaic shallow marine clastics
Tectonic Evolution of Sabah
- Located at a critical junction between the Eurasian, Indo-Australian, Pacific, and Philippine Sea plates
- Occupies a central position between three marginal basins: the Sulu, Celebes, and South China Seas
- Main tectonic elements include a major fold-thrust belt in the west (NW Borneo Trend) and a bending to the east and southeast (Sulu Trend)
- The arcuate belt contains a deep-marine Eocene-Oligocene accretionary complex
- The Early Miocene deformation marks a major tectonic event, causing the formation of mélanges, uplift, and erosion, which produced the Base Miocene Unconformity
- The Early Miocene deformation shifted the depositional environment from deepwater to shallow deltaic
- The collision of the Cagayan Arc and Palawan micro-continental block (Middle Miocene) caused the Middle Miocene Unconformity, also known as the Deep Regional Unconformity in Sabah
- The Late Miocene tectonic event represents another major folding and uplift, which is known as the Shallow Regional Unconformity
- The latest tectonic event was likely caused by strike-slip faulting and transpressional fault movement that continued from the Pliocene to the present day
Pre-Cenozoic
- Evidence of granitic and metamorphic rocks of possible continental origin
- Interpretation of gravity data suggests that normal continental basement underlies the ophiolite
- The Labang and Kulapis formations in eastern Sabah represent deep-water clastics deposited in a forearc basin setting during the Late Eocene to Late Oligocene
- Widespread regional subsidence occurred during the Oligocene, with outcrops of Labang/Kulapis Formation showing syn-depositional and syn-diagenetic extensional faults associated with this subsidence
Early Miocene Deformation
- The Early Miocene was characterized by tectonic deformation in the forearc region during subduction and widespread mélange development
- Inclusion of Labang Formation sandstone and mudstone clasts within the Gomantong Limestone indicates uplift and deformation began in the Early Miocene, between 22 and 20 Ma
- Deformation continued for several million years, with the Gomantong Limestone forming on structural highs during periods of quiescence in the Early Miocene
- An unconformity separates the deformed, lithified mélange unit of the Kuamut, Garinono, or Ayer formations from less tectonized strata
- The Early Miocene (22-20 Ma) deformation represents a significant tectonic event, causing the formation of mélanges, major uplift and erosion, which produced the Base Miocene Unconformity (BMU or Pre-DRU)
- This tectonic event is connected to the subduction and collision of the Dangerous Ground Continental Block with NW Borneo and is referred to as the 'Sabah Orogeny'
- The event transitioned the depositional environment from deepwater to shallow deltaic, providing sediment supply to the deltaic to shallow marine Middle to Upper Miocene successions of the Meligan and Tanjong Deltas
- The present outcrop pattern of the Miocene strata is a result of regional strike-slip and transpressional tectonics and inversion during the Late Miocene onwards and likely extending to the latest Pliocene
Late Miocene Deformation and Uplift
- Transpressional movement along major strike-slip faults in the region likely explains the structural development in these areas, potentially associated with the propagation of deformation from Sulawesi towards NW Sabah
- The Late Pliocene strike-slip deformation is extensive and occurred at a similar time as significant deformation in NE Kalimantan, Sulawesi, and NW Sabah
- This transpressional movement is interpreted as the cause of the major orogenic deformation, uplift, and final structural development in the Sabah region, potentially extending to the present day
- While the Late Eocene tectonic deformation is characterized by folding and thrusting of basement rocks and older Paleogene sediments, the regional tectonic setting of Sabah during the Paleogene appears quite complex, with southeasterly subduction in NW Borneo and extension in the SE in the Celebes Sea and Makassar Strait.
- The Early Miocene deformation is considered a major tectonic event, responsible for the formation of mélanges, major uplift and erosion, and the origin of the Base Miocene Unconformity. This event was followed by a change in depositional environment, transitioning from deepwater to shallow deltaic.
- The Kuamut Formation is linked to Late Oligocene sedimentation on the flanks of an accretionary wedge, but as noted above, it is an Early Miocene formation, and is an extensional mélange or olistostrome deposit.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore the geological evolution of Sabah, Malaysia, focusing on its complex rock formations and tectonic activity. This quiz covers the different stratigraphic layers, including the Crocker, Trusmadi, and Kudat Formations, and their significance in understanding the region's geological past.